July 2021 Get Together at Cedar Creek Cinema - Speaker Evaluation

[AudiocRaver]

The Setting:

We are gathered together this 4th of July weekend for holiday festivities: barbecue from Hook's BBQ of Troy AL, and fine music delivered by way of some of the planet's finest audio equipment. “We,” in this case, refers to AV NIRVANA's Sonnie Parker, Dennis Young, and Wayne Myers. The audio equipment includes a pair of MartinLogan Renaissance 15A electrostatic loudspeakers, a pair of Revel PerformaBe F328Be tower loudspeakers, a pair of JTR Noesis 210RT tower loudspeakers, and a pair of Adam Audio A7X powered near-field monitors. The gathering place is Sonnie’s Cedar Creek Cinema in warm, beautiful southern Alabama.

Sonnie usually has some new gear in play. This visit it includes a Roon Audio server, a miniDSP SHD streaming processor with Dirac Live for our music listening, a Monoprice Monolith HTP-1 audio processor with Dirac Live for our evening cinema experiences, 2 Sanders Magtech power amps - each with the rail fuse removed from one channel, thereby only using one channel in each of 2 different stereo power amp chassis to power the left and right main speakers, and an Emotiva Eleven 13-channel power amp for the surrounds and overheads. A Panasonic DP-UB9000 disk player rounds out the lineup for Blu-ray and UHD 4K movie disks.

Subwoofers available are all from SVS: 4 SB16-Ultra for optional use with music, and 2 PB16-Ultra in addition for use with movies. That's right, all 6 of them with movies. Zowie!

Center, Surrounds, and overheads are all MartinLogan: Center, ML ESL C18 Focus; Side (2), ML EM EFX; Back (2), ML EM ESL; Height (4), ML Motion AFX.

A wide array of new treatments and furnishings are in place as well, part from GIK Acoustics, and the rest hand crafted by Sonnie himself.

Much delicious work is to follow, including a BBQ lunch of ribs, pulled pork, and chicken, BBQ beans, and dirty rice, with seven layer salad and home made chocolate eclair for desert, prepared by the loving hand of Sonnie's mom, Ann.

Thanks to Sonnie, Angie, and Gracie for hosting. There is much work to do. Just a sec', gotta loosen my belt.

We will report.

Evaluating Speakers:

The main purpose of this get-together is to evaluate speakers. Groups have been gathered numerous times to Cedar Creek Cinema for speaker evaluations which involved an array of speakers within a price range, including a half-dozen or more speaker pairs, usually towers, often including an atypical panel pair or horn-loaded pair, but usually centered on more common cone/dome designs - not to minimize in any way the amount of engineering time and effort that generally goes into any type of high-fidelity loudspeaker. With electrostatic panel speakers being Sonnie’s established personal favored listening type, and an underlying question often being, “Should one of these speakers be my next front mains pair?” there was often a pair of electrostatics in the mix.

Our evaluations have always been as thorough as is practical in an intense (but always fun), focused 3- or 4-day weekend with several experienced critical listeners and Sonnie at the helm as Chief Critic and Clock Watcher.

Our priorities and approach have been honed, but overall remain unchanged:

• Setup for razor-sharp, accurately placed, stable imaging across a continuous, expansive, engaging soundstage (SS&I) with minimal sacrifice in frequency response. The speakers should completely disappear in the soundstage. Sometimes this setup takes a few minutes, but in some cases we have spent hours on a speaker model, going to ridiculous extremes and leaving no stone unturned chasing that goal.
• Correct frequency response, if needed, with room correction DSP, using an agreed-upon target curve. Room correction invariably improves L-R speaker matching, thereby always focusing the imaging at least a little and sometimes a lot, so we apply it as a matter of course. The arguments against doing so are overridden by effective room design and treatment and by our own collective ears which agree that - under our conditions - there is always some improvement. Our tool of choice for room correction is Dirac Live, which provides the best room correction benefits with little or no downside. Any undesirable effects we have encountered result from our application of the tool, perhaps in pushing woofers too hard through emphasized bass with the target curve, for instance, and we then make needed changes to the correction. This week we generated two room corrections per speaker, one correcting the full frequency range, and the other only up to around 600 to 800 Hz, so we could compare the two. Sonnie's post covers this in detail.
• In some cases we have briefly set speakers close to the front wall of the room to satisfy forum reader requests, although the sonic result is rarely acceptable to our ears. During this eval weekend, we did not do this.
• Measure, measure, measure. Room EQ Wizard (REW) is our tool of choice. These measurements are primarily at the listening position (LP).
• Give each listener a chance to listen and evaluate, in this case we planned for almost unlimited listening time. These are sighted evaluations. We do our best to avoid comparing findings until all listening to a pair of speakers is done and all opinions are independently formed. More than once this has involved private discussion with Sonnie away from others, as Sonnie is the test implementer this weekend.
• Compare findings.
• Where warranted, reposition, remeasure, and re-evaluate. Leave no stone unturned.
• Document and report.

Four Speaker Models and Types:

We had four speaker pairs to evaluate. Each of these speaker types set up in Sonnie’s room seemed like a very different animal, making it difficult for any simple, direct comparison. It is worth noting that the soundstages we heard are different with these four designs. In the paragraphs below, there will be a few comments about this before links directing the reader to the individual speaker evaluations. Lest one be tempted to think of one design or another as the ideal soundstage generator for some reason, remember that it is the degree to which the soundstage engages the listener, along with listening purpose and listener preference, that reveals the final answer to the question, “Which soundstage is best?”

MartinLogan Renaissance 15A Electrostatic Loudspeakers. The electrostatic panel portion of the 15As is a dipole design. Sound radiates equally from the front and rear of the panel, with the rear signal's phase inverted. The front and rear waves are beamed fairly tightly, with the rear wave largely absorbed by room treatments, and the front and the phase-inverted rear signals summing to almost no radiation to the sides, up, and down. The result is very little room interaction with the 15As at panel frequencies, except for the delayed, unabsorbed portion of the rear wave.

So the soundstage is primarily that which is contained within the recording with the delays and ambiences as recorded and mixed, with some added briefly-delayed rear wave signal lending a small amount of room ambience to the sonic conglomeration. The resulting soundstage is mainly the recording's soundstage with some room influence added in.

Read the MartinLogan Renaissance ESL 15A Review HERE:

Revel PerformaBe F328Be Tower Loudspeakers. The PerformaBe are a cone and dome tower speaker, designed with controlled directivity in mind. Its curved surfaces assist the coupling of off-axis sound to the room so that there are no severe discontinuities in off-axis response. Think smooth, rather than flat, off-axis response. The room will be engaged in a big way with such a design.

The resulting soundstage is roughly equal amounts of the recorded soundstage and room influence.

Link to Revel PerformaBe F328Be evaluation:comments

Link to Revel PerformaBe F328Be evaluation comments REVISITED

JTR Noesis 210RT Tower Loudspeakers. The 210RT makes use of a coaxial compression driver coupled to a horn for delivering mids and high frequencies. With a well-designed horn, those frequencies are beamed at the listener with very little sound wrapping around the speaker enclosure to be heard by the listener as delayed, reflected sound. This type of speaker is often favored by those who have “difficult rooms” with severe asymmetries or reflective surfaces that cannot be treated easily. We think of the horn-loaded design as a “room eraser.” The influences of the room are severely limited with this design.

The resulting soundstage carries the listener deep into the recorded material’s soundstage, with little to no room influence.

Link to JTR Noesis 210RT evaluation comments

Adam Audio A7X Powered Near-Field Monitors. The A7X is a very small point-source speaker. Its design couples a great amount of sound to the room for delayed reflections, doing so with controlled-directivity in mind, so smooth off-axis response is key to its soundstage generation. This type of speaker will generally be close to the listening position.

The resulting soundstage is roughly equal amounts of the recorded soundstage and room influence, with the ratio tipped a little more toward the direct signal, the recorded soundstage, than the room influence. This ratio also applies to the lengths of reflection delays relative to the direct-to-ear signal.

Link to Adam Audio A7X evaluation comments

========

This thread is open for comments. This first post will be added to through the GTG, with links to detailed reviews for featured speakers and specific pieces of gear.

 

[Sonnie Parker]

EXcited to have Wayne and Dennis here again. The company of serious ears and good friendship is always welcomed and enjoyed.

I may have very well ate too much yesterday.

After last years bomb with two processor units and a pair of speakers wimping out on us, wasting a lot of our time, we are off to a fabulous start. We have faith in the equipment and the speakers are working as they should thus far. Thankfully it has been nothing but super fun. Off to worship service and then we'll resume the party!

 

[Sonnie Parker]

We listen to all speakers with and without subs, with and without Dirac... full and partial correction.

The first day we spent listening to the MartinLogan 15A's... second day was the Revel F328Be's... and the third day (today) we are listening to the JTR 210RT speakers.

 

[tesseract]

It's good to be back in 'Bama, with my old friends and new gear to enjoy.

I started my journey off by landing in North Carolina to listen to Wayne's system. I don't mind saying that it was one of the best audio experiences I've ever had, anywhere. Everything carefully dialed in with lots of attention given to room treatments and DSP assistance.

We then stopped in South Carolina to swing by the JTR factory, have lunch with Jeff, meet a couple of the assembly workers and to pick up the Noesis 210RT pair.

Wayne and I drove the rest of the way though SC, into Georgia, finally arriving at the Cedar Creek Cinema in Alabama later that same evening.

We are steadily cycling our way through the various speakers and DSP programs. I'll post up some glamour shots when all the stars have crossed the stage. Stay tuned...

 

[tesseract]

MartinLogan Renaissance ESL 15A

Revel PerformaBe F328Be

JTR Noesis 210 Reference Tower

ADAM Audio A7X.

 

[pratul]

Dang it! I missed this post! I would have certainly been there.

 

[Sonnie Parker]

We would have welcomed you too... it would have been fun.

I have posted the DSP testing we did during the event: https://www.avnirvana.com/threads/dsp-eq’ing-full-range-or-not-–-testing-the-ears.8992/#post-69168

 

[AudiocRaver]

MartinLogan Renaissance ESL 15A Electrostatic Loudspeakers

The MartinLogan Renaissance ESL 15A Electrostatic Loudspeaker features a 46-inch x 15-inch Curvilinear Line Source electrostatic panel with its controlled dispersion radiation pattern above the 300Hz crossover frequency, and two 12-inch woofers, each powered by a 500 watt (1000 watt peak) class-D amplifier, and the frequency range below crossover is ARC Ready (having Dirac Live on hand, we never used it). The woofers are situated at the front and rear ends of the base of the 15A's, sealed in separate enclosure compartments. The length of the base, along with special crossover phase tuning for the two drivers, helps eliminate low-frequency response anomalies by reducing the effects of reflections from the front wall, a real problem for most full range speakers. Looking at one of our measured frequency response curves, taken without ARC or Dirac room correction, and without subs in play, I cannot remember seeing a bass response curve so flat from any loudspeaker we have evaluated, clear down to 20Hz.


Sounds Like Home

The Renaissance ESL 15A pair has been in place in Sonnie’s room for many months. His listening position (LP) has changed, too, moved forward by a foot or so, and he has spent a lot of time refining the positions of the LP chair and speakers for ideal soundstage and imaging (SS&I).

When we arrived at Cedar Creek Cinema, our first task was to make sure they were ideally placed. It took us only a few minutes to determine that they were in the best placement we were likely to come up with. And there was no need to check for sloppy setup symmetry, Sonnie being about as fanatical as one can get about such matters.

One of the first things that I noticed was that he had arrived at a toe-in angle that looked the same as what I had arrived at for my pair of MartinLogan Classic ESL 9's back home, a somewhat shallower toe-in angle than we have tended to use in the past. A setup with zero toe-in angle, aimed straight at the listener, will deliver the flattest frequency response, but the soundstage and imaging (SS&I) - depending on the loudspeaker type and design - will generally be flat and lifeless, if not downright horrible. MartinLogan’s curvilinear electrostatic panels give the listener a range of possible listening angles for good SS&I before the high frequencies roll-off too steeply to be usable.

Another similarity between Sonnie's set up and mine back home was the use of absorption for the entire front wall, minus the area of the projection screen in Sonnie's case. So I had high expectations for success as I sat down to listen for the first time to the Renaissance 15A.

I was not disappointed in the least, and had the same reaction that I have experienced many times sitting down to a new pair of MartinLogan electrostatics to listen at a trade show or after returning home from one. There is a comfortable sense of being home, electrostatics being so easy to love with their completely effortless delivery. It is as though the air is simply enticed to vibrate with music somehow, with no involvement of any electro-mechanical device.

This is almost true. The large surface area of super lightweight material that makes up an electrostatic panel barely needs to move at all to do its job, so even at higher volumes there is never any sense of strain in the sound coming from those panels. This has been the case over the range of MartinLogan electrostatics that we have evaluated, from the littlest brother EM ESL to the second to the top of their current lineup, the Renaissance 15A. You can turn them up until your ears cry uncle, and the music will always arrive with a sense of effortless ease.

Another feat of engineering that the MartinLogan engineers have mastered is that of integrating an electrostatic panel with a cone type woofer. I have yet to hear a model that failed to accomplish this seamlessly.

As Sonnie has written about in some detail elsewhere, we had decided to run Dirac Live calibrations for each speaker type, one with correction clear to 20kHz and the other with correction only up around 600Hz, several times the room’s transition frequency. We also ran a calibration including subwoofers, usually with a 20kHz calibration, and of course could listen without Dirac Live or subwoofers if we chose to.

Long ago we decided to trust our own ears and logic and to ignore advice saying never to run room correction above the transition frequency of a room. While there may be some truth to that advice in a horrible listening room, in our fairly- to very-well treated listening rooms there is plenty of upside with no downside from time-adjusting room correction, especially with our favorite tool, Dirac Live.

When it came time to sit for a serious listen, I started with no subwoofers and no room correction to get the pure MartinLogan reference point. I have listened like this with my Classic 9's for months at a time when other parts of my system were in flux and a Dirac Live calibration was not convenient. As one would expect, the Renaissance 15A's have a much flatter uncorrected frequency response than my Classic 9's. The 15A's are voiced with a slight rise between 1-2kHz, and from there the HF response drops only slightly to 10kHz and beyond. The flatness of the uncorrected LF response down to 20Hz was simply mind-boggling.


Listening Tests
Without subwoofers and without room correction, although room correction could be selected for comparison (described below):
Désolé, Gorillaz: The strummed electric guitar, panned half right, seems super-enhanced. We have measured left/right speaker response matching at the LP and it is superb. Imaging is excellent, highs are smooth and balanced, and the soundstage has the beginnings of depth acuity, or precise depth perception, an elusive quality. The horns and strings later in this piece stand forward with a similar enhanced quality.

Supermassive Black Hole, Muse: This is a fairly flat mix, but the lead guitar panning back and forth gives one a chance to listen for obvious holes or discontinuities in the soundstage. There are none that I can hear. Even at higher volumes I do not miss subwoofers at all with this song.

Compassion, Todd Rundgren: The soundstage depth is so distinct and clear, and seems overall a bit deeper than with Dirac Live. I love how the shimmering glockenspiel sparkles and stands out.

The 15A's completely disappear in this setup, with and without Dirac Live. Some speakers need a little extra help from room correction for that to occur.

With Dirac Live room correction, 2 settings, one corrected full bandwidth to 20kHz, the other corrected to 600Hz. Optional subwoofers were rarely engaged:
With Dirac Live engaged, image clarity and precision were improved by a notch, as predicted, and that elusive sense of depth acuity, which might go hand-in-hand with the unruly exuberance of the raw 15A soundstage, was definitely toned down. One experiences a soundstage that fills the end of the room, extending well past the speakers horizontally, filling the room vertically and with depth from the plane halfway between the LP and the electrostatic panels to the front wall of the room.

Perfect World, Broken Bells: The opening notes are like the conductor tapping the music stand with the baton and calling the orchestra to order, exuberance contained, precision delivered, mission accomplished. The kick drum is now a tightly focused entity front and center, low in the soundstage.

Ain't It A Shame, The B-52’s: There is a vocal echo that appears high and to the right that, for all its delicacy, is so distinct that it might have a heavy outline around it. The 12kHz sheen on Cindy's voice always grabs me.

Vision Of A Kiss, The B-52’s: The focused kick drum owning its space, a pair of notes strummed on an acoustic guitar declaring, “I want to be a real guitar,” then a solid bassline underscoring all of the above with authority. Details like this from familiar test tracks confirm sonic truths about a loud speaker. Lest they become boring with repetition, we are reminded once in a while of being tickled to laughter when we first discovered them years ago. What fun.

Another Nail In My Heart, Squeeze: Drums, bass, and guitar are pulsing and then tumble down towards the chorus with a sense of urgency. When your loudspeakers get out of the way of the music like these Renaissance 15A's do, it is as though the inner intentions of the songwriter and performers can find a way to speak to you directly.

China Girl, David Bowie: Bowie’s vocal tone and expressiveness have an etched quality about them insisting they be committed to memory.

I Love You. Climax Blues Band: Faithful reproduction of cymbal tones like those recorded in this track is a task often overlooked. The extended highs from the 15A's make every little ping and ting a beautiful thing.

Beyond The Blue, Beth Nielsen Chapman: The room is filled with gently pulsing drums, which are accented by the strums of an acoustic guitar, then Chapman’s beautiful vocal quality sews it all together like a silver thread.

Don't Panic, Coldplay: This first track from Coldplay's first album has a raw quality that sounds like they're just warming up. The guitar panned hard left, then second guitar panned hard right, then Chris's unapologetic first vocals dead center underscored by an almost thunderous bassline, then it all melts together into the dreamily reverberant chorus, “We live in a beautiful world.” The Renaissance 15A's are capable, like few speakers, of reminding us through music that we do live in a beautiful world, “yeah we do yeah we do.”

Float On, Modest Mouse: The analog console saturation uniting the vocal parts on the chorus is the kind of detail a lot of speakers would leave buried behind imperfections. The 15A's cleanly deliver the inner details of recordings.

Trouble With Dreams, Eels: High bells dominate the chorus of this Eels song, caressing from left and right Everett’s scratchy voice that seems always in pain yet always on pitch, then the bells complete the filling in of the soundstage behind him. An expansive soundstage full of tiny bells is a thing to behold.

Session 2:
After a break I approached the 15A's with fresh ears for a final listen. Through the previous session, I had switched back and forth often between the two Dirac Live filter presets that corrected full bandwidth and to just beyond room transition frequency. As one can see in the frequency response plots, there is not a big difference between the two. Listening to both, in this room with these speakers, there is no right or wrong, better or worse about it, simply a personal preference. At times I enjoyed the natural voicing of the 15A's with mids and highs unfettered by the room correction, at others the precision of the Dirac Live correction all the way to 20kHz, and it was fun being able to easily switch back and forth between the two. Given a few more preset spaces in my NAD T758 v3 AVR back home, I might just add that option for the fun of it.

For this final short session, I focused on that difference more closely with these tracks. I had rarely in the previous session turned on the subwoofers, finding no benefit from them for my own taste and tracks and I did not turn them on at all thru this last listening session with the 15A's.

Time Heals, Todd Rundgren: I can hear the mids held back by the Dirac Live full bandwidth room correction relative to the more lively natural delivery of the 15A with partial correction. No preference here, both were enjoyable to my ear.

Compassion, Todd Rundgren: The sampled glockenspiel got me thinking that while the soundstage difference between partially corrected and full bandwidth corrected is small, I had found the soundstage difference between uncorrected and partially corrected fairly significant. Since returning home, I have found the same to be true with my own system, but I am far from attempting any conclusions and claim no in-depth understanding of the phenomenon. It's a mystery, something to be looked into later on. I enjoyed this particular track more with the partial Dirac Live correction in place, allowing a little bit more shimmer and liveliness in the glockenspiel sounds, all up in the higher frequencies.

Love Science, Todd Rundgren: I had no preference with this track.

Still Island, DJ Crush: Mixed in a way that almost seems unruly in places, I like the way the full band correction seemed to regulate this track.

4Ware, Deadmau5: I definitely preferred the full band Dirac Live correction for this track. With synth notes appearing in almost every available position of the sonic space, that brought about a sense of order to the track.

Late In The Evening, Paul Simon: Another toss-up, I enjoyed listening to it with either correction option.


Conclusions

The MartinLogan Renaissance 15A electrostatic loudspeakers pushed all the right buttons for me. I would personally never find the need to buy a subwoofer to go along with these speakers in a two channel application. The low frequency energy from the Renaissance 15A is monstrous, impeccably clean, and accurate. You might have to start telling yourself bigger lies to justify that next subwoofer, the 15A’s will not help you.

I also found the Renaissance 15A to be a superbly enjoyable speaker without any kind of room correction, delivering sharp, accurate imaging, a soundstage that will steal your heart, and clean, effortless delivery full of inner detail. Of course the beauty of adding Dirac Live is that it takes all that good stuff and makes it even better.

Now we just have to nudge Sonnie into moving up to a pair of Neoliths for our next GTG.


Sonnie's Biased Take
Ascent i, Spire, Prodigy, Montis, ElectroMotion ESL, Expression 13A, Classic ESL 9, and finally after 14 years, the Renaissance ESL 15A. How can I not be at least a LOT biased? Simply put... I've never heard a speaker that can immerse me into the music with superb imaging, image layering, depth acuity, and a huge soundstage like the 15A's provide in my room, all at anywhere from low listening to insane levels without any stress on the speakers. It has literally been the perfect pair of speakers for me, leaving me wanting for nothing else. Sure... other speakers are interesting, but the 15A's are my magic. I listen to more music than I have ever listened to, constantly searching for new stuff to test, and they continue to amaze me over and over... never tiring me in the least bit. I'm really not sure what else I can say. I'll echo all of Wayne's comments, as I've listened to everything he has listened to, and our thoughts are very similar, if not exact in most cases. I suppose I'll add that unfortunately I think I'm at the top with MartinLogan, as the Neoliths are a bit out of reach financially, although it sure would be fun hearing them in my room.


Dennis's Impressions:
Once again, I am extremely familiar with the Martin Logan sound, having heard many systems featuring the brand, having heard almost all of their electrostatic speakers. The Renaissance ESL 15A is one that I do not recall experiencing. Just like Wayne's desire to own JTR, I am planning to get myself something different that does fit my budget and the smaller second listening room I have. That something different will most likely be the more affordable and best fit for my room, the EM-ESL panels. I do like directivity designs, after all. I've said this to Sonnie and Wayne many times and now I'll say it to you. Dipoles share a lot of sonic attributes with horn speakers. It's counter-intuitive, but absolutely true.

Don Felder "Heavy Metal" had a mellow, laid back nature and requires a "heavy" hand on the level control to get the track up to listening "speed". with any system I've played it on, the track lacking kick. The 15A accommodated my request, the SS&I was top-notch and much appreciated.

"I Will Always Love You", Dolly's voice in present and accounted for, front of stage, slightly muted in character. The ML's put an ever-so-slight haze over the presentation, much akin to the even-order harmonic distortion that makes tube amps sound so pleasing. It also throws up a huge soundstage with lots of air between the images, it's biggest strength. Life-sized sound, that is Martin Logan's signature.

Bass is aplenty. I tried subs in and out and I was almost always completely satisfied with the low frequency reproduction, with the exception of but a couple songs. Even so, I could happily do without subs for 100% of listening, if I had too, no problem. We didn't have to, though, so the extra little bit of heft was noted, appreciated and registered as a welcome addition, but not an absolutely necessary one.

I can see why Sonnie loves these speakers so much and I do, too. They are out of reach for me, financially, but if I had the means, there would be no hesitation. I spent a lot of time with them, listening late into the night after our critical evaluations on two occasions, at least 80% of that was sans subwoofer augmentation. I actually miss these speakers, something that rarely happens to me anymore, having assembled a couple of decent systems at home. The ML are as impressive to look at as they are to listen to. Tall line-source coupled with dipole radiation, a true controlled-directivity design that ignores room ceiling, floor and side wall reflection, in a single panel that mates concisely with a matching front/back dipole subwoofer system that can be DSP-tuned to deal with the modal issues that are the biggest problem most (all?) audiophiles face in domestic situations.


MartinLogan Renaissance ESL 15A Electrostatic Loudspeaker Specifications

• Enclosure type: Non-resonant asymmetrical dual chamber format
• Frequency Response: 22Hz - 21kHz +/-3 dB
• Impedance: 4 ohm, 0.5 ohm at 20kHz
• Sensitivity: 2.83V @ 1 m = 92dB
• Dimensions: 69.8" H x 15.75" W x 28.9" D
• Weight: 140 lb

Retail Price: $27,499.98 per pair


Measurements
All measurements were taken at the Listening Position (LP).

Left and Right Uncorrected Frequency Response (FR)

Left Speaker FR: Uncorrected, Partial Dirac Correction, Full Range Dirac Correction; Full Range Dirac Correction plus subs

Impedance and Phase. It is because the bass drivers are internally powered that the impedance is so high at low frequencies, essentially the input impedance of the internal power amp.

 

[AudiocRaver]

Revel PerformaBe F328Be Tower Loudspeakers

The Revel PerformaBe F328Be is a 3-way floorstanding loudspeaker featuring a 1-inch Beryllium dome tweeter driven by dual ceramic magnets, mounted amid a ceramic-coated, cast-aluminum acoustic lens waveguide. The tweeter/waveguide combination’s directivity and that of the 5.25-inch midrange meld together at their 2.1kHz crossover for seamless emanation of those frequencies into the listening area. The three 8-inch woofers have deep ceramic composite aluminum cones and cast frames.


Wayne's Comments

I had looked forward with a bit of excitement to my first focused listening session with a pair of Revel speakers, the Revel PerformaBe F328Be floorstanding loudspeakers. The F328Be model’s big brother, the Salon2, along with the older Salon, have found their way into high-end mastering labs as a reference system. With the F328Be using the same beryllium dome tweeter, acoustic lense waveguide, and midrange driver as the Salon2, we expected the midrange clarity and high frequency transparency to be representative of Revel's best.

Having had the chance to step into many demo rooms at audio trade shows, and having been disappointed many times by high-end speaker systems with dome tweeters, the few designs with truly transparent-sounding dome tweeters have gotten my attention. Without fail the tweeter dome material has been beryllium. One speaker designer explained that beryllium has less of a tendency to break up and distort then aluminum or titanium, and when it does the distortion generated falls well above the range of human hearing. So, all factors considered, the F328Be’s promised an evaluation session that would be a real treat.

When I finally got to hear the F328Be’s after their initial setup, it was with some delight that I noted the super clean mids and smooth highs that, while transparent to the point of near invisibility, had a way of standing forward proudly. They reminded me of the super clarity of the best ribbon tweeters, the RAAL tweeter being one that I think of. I have a bit of a crush on the RAAL for its unabashedly forward yet liquid smooth high frequency delivery. The highs from the F328Be strongly hinted at such possibilities.

The starting position for the F328Be’s was the same spot where the Renaissance 15A’s had performed so well. Then they were nudged closer together to help fill in the middle area of the soundstage, then toed inward to sharpen the imaging. At that point they were still within inches of that favored location where we expected reasonably good bass response. Then we performed a set of Dirac Live calibrations and it was time for a serious listen.

I enjoyed several tracks, starting out at moderate volume. But then a deadmau5 EDM track, with its heavier bass lines and with the volume turned up a bit, revealed an area of bass resonance with serious mushy distortion. The Dirac Live filter set, with a little encouragement of our own to make up for some uneven bass rolloff, was pushing the F328Be woofers well beyond their comfort zone. We made a couple of passes at softening the amount of correction from Dirac Live but could not come close to being able to get even bass response without that booming, mushy distortion.

Somewhat disappointed, we decided to set the F328Be’s aside and proceed with the next speakers on our list. In doing so, we discovered another spot in the room where solid, even bass response could be hoped for from the Revel’s. Later, we moved the F328Be’s to that pair of spots to give them a fair try there. With some additional jockeying to improve SS&I, a good compromise was reached, including freedom from serious LF distortion with much flatter response. But the Imaging was soft enough to be considered unsatisfactory, well below our normal standards, and far below what we already knew them to be capable of.

After a bit of deliberation, we decided to adjust the F328Be toe-in inward a little tighter, hoping the move would sharpen the imaging toward that which we had witnessed earlier. It did so quite nicely, but now we were baffled to hear some of the LF problems returning, more of that mushy resonance.

After a break and more discussion about our experience so for with the F328Be’s, we decided that, in terms of performance, that model speaker in Sonny's room was like a puzzle. We had gone above and beyond trying to get all of the performance pieces of that puzzle fitting together at once at different locations in the room, but there was always one essential piece left over that would not fit. And at that point in time we had two other examples of well-regarded speakers that had required no such gyrations and had delivered with all of their performance puzzle pieces fitting together marvelously.


Moving On

I am still a little saddened by these events. The F328Be showed such promise, but the setup that allowed the F328Be’s to truly shine simply eluded us. Maybe a few more minutes would have done it, maybe a few hours, and maybe we would never have achieved it.

The bass section, the drivers and the cabinet tuning (we tried combinations of the supplied port plugs, they were no help), perhaps with the crossover playing a role, did NOT like being pushed. Even a little bit of bass boost to flatten bass response was met with complaint. We have allowed Dirac Live to flatten the bass response of many a speaker system in that room, including one tower I can think of that crushed those bass tones easily and with no ill effects, and that cost less than 1/10th the sticker price of the F328Be’s.

I wonder if room size is an important factor for them, if they would do better in a smaller room. Perhaps if we had perfected the SS&I... then pulled the walls of Sonnie’s room inward until the bass behaved and flattened out… then corrected with Dirac Live for that final polish… Perhaps we would be telling a different story.

The F328Be’s took a lot of fiddling and, although they were close, they ultimately rejected our insistence upon doing all of the right things at once. Convinced we had done our due diligence, we decided to move on. For all their good points, it appeared to us that the F328Be’s were just more trouble than we had time for. Three pairs of experienced ears with a ton of speaker setup experience and top drawer measurement gear were not able to get them sounding right, and we can not give the F328Be our recommendation as a two-channel speaker choice in a home theater of medium to large size, even a well treated one. Given Revel’s reputation for reference level high-end towers, others must have found a way to get results that satisfy their expectations. We could not.


Sonnie's Take:
I've heard a lot about how great Revel speakers are, read all the reviews and lots of owner's comments about various models. The biggest takeaway from what I read was they are very neutral and have wide dispersion characteristics with excellent off-axis response. There sure isn't too much negative about these anywhere, thus I had to have a pair to check out and see what all the fuss was about. I wanted the F208's, but they are out of production, therefore I settle on ordering the F228Be, which I did direct from Revel. A few weeks later I was told they were several months backordered, and they could instead send me a pair of F328Be. That was even more exciting after reading the glowing reviews from well-respected publications. This all worked out really well for our evaluation event, giving us a really high-end speaker to capture our attention. I thought the F328's were a pretty good speaker when setup correctly, but that wasn't such an easy task for us in my room. We spent an enormous amount of time trying various locations and placements... picky, picky, picky in my room for some reason. I preferred one location, while Dennis and Wayne preferred a slightly different location, and we all heard different results. When placed where I preferred them, wide and toed-out a bit more, they had good imaging and a respectable soundstage, although not quite as big as I would have expected or preferred. The center imaging was good, and off-center imaging was pinpoint. When moved in and/or toed in slightly more, the center image tightened up, but the off-center imaging started smearing (wondering) slightly on my favorite imaging song, Strange Fruit by Cassandra Wilson. The bass was also a bit shy for me, and thus I preferred them with the subs exchanging crossovers at 80Hz. We never could seem to get it all to come together perfectly with the F328's. I am curious as to what was causing the issues for us and why we didn't seem to like these as well as I thought we all would. It may be that we had our expectations too high from all the hoopla published about them, which you would think might have caused us to have more positive bias towards them. Perhaps the wide dispersion characteristics don't do well in my room, being that I seem to prefer the narrower dispersion type speakers that I've recently been using and have evaluated in my room. I don't think I'm intelligent enough to say for sure. Unfortunately, the F328Be just didn't live up to what I thought they would be. A very good speaker... yes, but a great speaker, no... not for me. I'm sure there are a lot of rooms these will sound spectacular in, and there will be many happy owners of the F328 in the years to come. So I encourage you to not allow this evaluation to discourage you from trying them in your room, as your outcome may be exactly what you are looking for, as they have been for many owners.


Dennis's Impressions:
My first impression of the Revel F328Be is that they were not comfortable at high levels and were a bit light in the lower bass region. Probably my favorite of the group for midrange clarity, but the overall impression is one that has struck me with every previous Revel audition, which is they are a bit boring to me. That might actually be its best attribute when looking for absolute accuracy, as these are purported to convey accurate reproduction better than most anything else out there, but the brand has never rang my bell. This time around, I had a hand in being able to position them and massage the DSP in a purpose-built dedicated room with two other avid audio enthusiasts. Postioning this pair of speakers proved to be an exercise in futility, never have I seen such a picky speaker. Great off-axis response is supposed to help in that regard. What's going on here?

"Happy?" by Mudvayne is a decently-recorded metal track that helps me pull apart what a loudspeaker system can do. the lyrics "Dirt shoveled over shoulder", "Peel me from the skin, tear me from the rind" coming though more clearly than heard before on any system. It's a good start, but the SS&I is not how one expects stereo reproduction to sound, it just wasn't gelled.

"Abracadabra" by the Steve Miller Band gave me hope and was a fun listen. All was still not well, though.

London Grammar's "Hey Now", the bass almost present and accounted for. There is a lot of woofage going on here with these towers and I would normally expect MOAR, but it was palpable, at least. SS&I was acceptable...

With Blue Oyster Cult "Godzilla", the Revels rocked! No deep bass is to be had on this recording, so that wasn't missed. The smooth pan the guitar at 26 min. from left to right was well-preserved. I was about ready to cheer. Finally, a Revel I can warm up to!

Kill The Noise, Feed Me "I Do Coke (Snort and Leisure Remix), at the 1:31 mark, there was a pronounced snap to the midrange electronic percussion that the Revels did not like. Could the mid driver powering this portion of sound use a little more protection, a steeper roll-off and/or higher crossover frequency? I am not going to pretend for a second to know but a small fraction of what the combined engineering team at Revel, people that I respect very much, know. I do know that I had to back off the Revels as they were getting quite upset with me.

When we added subs to the mix, everything became much better. I hit the system with Bassotronics & Bass Mekanik "Bass, I Love You" (comma added by my OCD), all was well, frequency-wise. No bottoming, just a nice electronic deep dive with the requisite mids and the sooper-clean, piercing highs that this song contains. The F328Be pair smiled at me and I smiled back.

The good 'ol "More Than A Feeling" by Boston confirms that much had changed. High-level listening became more relaxed, The Revels became more comfortable and were now able to stretched their legs. This relaxation of the speakers allowed the soundstage to widen and extend beyond the speaker edges, the speakers now calling less attention to themselves. The lesson here is that the F328Be does not like to do bass. Don't even ask them to. That aside, once the bottom octaves were handed off to a subwoofer system, I warmed enough to the Revels that, at the end of my listening session, I wanted to go over to one (or both) of the speakers and shake their hand(s) and put our differences behind us. Such a pain to place, though, we never did become more than acquaintances, unfortunately.


Revel PerformaBe F328Be Tower Loudspeaker Specifications

• Enclosure type: Dual rear ported bass reflex
• Frequency Response: 26Hz - 40kHz -6dB
• Nominal impedance: 8 ohm
• Sensitivity: 2.83 V @ 1m = 91dB
• Dimensions: 50.9" H x 13.5 " W x 17.6" D
• Weight: 112.6 lb

Retail Price = $16,000.00 per pair


Measurements
All measurements were taken at the Listening Position (LP).

Left and Right Uncorrected Frequency Response (FR)

Left Speaker FR: Uncorrected, Partial Dirac Correction, Full Range Dirac Correction with subs,

Impedance and Phase.

 

[AudiocRaver]

Revel PerformaBe F328Be Floorstanding Loudspeaker REVISITED

After returning home from our get-together, I did some digging into the REW measurement files looking for evidence of what we heard with the PerformaBe F328Be’s in their final configuration, hoping to find an explanation and perhaps even a solution for the problem. Unfortunately, we did not, but we thought the process might be of interest to the reader who likes digging deep for answers to weird questions. All of the following plots are with the F328Be’s in their final configuration and were measured at the listening position (LP).

The left and right raw frequency response plots show nothing that appears to be a problem, although the dip in frequency response at 74Hz has the potential of becoming one if Dirac Live has to boost that frequency very much.

There is quite a bit of boost by Dirac for the left speaker. Red plot is rew FR, Blue is with full correction, Green is with room mode correction only.

To see the details of what is going on, it can be helpful to look at the FR plots without all the smoothing we normally use. With smoothing set to 1/48 octave, it is apparent that there is substantial boost at 74Hz. Green is uncorrected, Orange is full correction.

Here is a more detailed view at that frequency.

Calling upon REW's "A over B" trace arithmetic function, we see a 9.2dB increase in gain at the frequency in question. That means close to a 10 times power increase, which sounds like a lot, but considering their efficiency is 91dB and the fairly low measurement level, along with the moderate listening level when we noticed the problem, the right F328Be could not have been receiving more than a few Watts of power from the amplifier. It seems pretty safe to say that this is not a problem of overtaxing a power amplifier or a large tower speaker.

The Distortion plot at that frequency shows nothing to be concerned about. This plot is for the right speaker, which turns out to be where the problem lies. The noise floor for the left speaker’s distortion plot shows some room disturbances making the plot unusable. Although we were normally very careful to be quiet during all measurement taking, occasionally there were small noises that would be unnoticeable on a frequency response plot, but quite obvious on a plot which requires a low noise floor like a distortion plot. My own practice at home is to take a quick glance at the distortion plot after each frequency response measurement to make sure there are no footsteps or dog sounds or refrigerator compressor noises messing up the noise floor. At future get-togethers, we will redouble our efforts to be extra quiet during all measurement taking.

The plots we are looking at for the F328Be are the full range Dirac correction plots. Just to be sure there was no significant difference in the room mode correction plots, here is a glance at the same frequency response range with only room mode correction. There is no significant difference.

Looking at other views of the measurements we have taken, I am a little concerned with the group delay. With no room correction active, here are the left (Red) and right (Green) group delay response plots at low frequencies. It is a concern to see the difference between the left and right, and the magnitude of the right speaker’s group delay at 74Hz.

This is a bit of a head-scratcher. Diraz Live is not engaged. Could there be some difference between the left and right speakers themselves? A defective speaker? That seems unlikely but is not impossible. A difference between the left and right speaker interactions with the room? Ludicrous. We go to a near obsessive level of detail making sure that set up dimensions are symmetrical to better than 1/4 inch. Sonnie’s room treatment and room construction were carried out with the same zeal, with overkill at every turn. At this point at least we can tell that the problem points to something interacting with the right speaker, and the same thing did not happen on the left side, so the right side seems to be the one to be looking at more closely.

Now we are looking at the difference between the raw (uncorrected) group delay for the right speaker (Green) and the full range room corrected group delay (Orange) for the right speaker. Whatever is going on is somewhat accentuated by the engagement of Dirac Live, but not by a huge amount.

Here is the first indication of what we might have actually been hearing. The spectrogram for the right speaker with full range correction engaged shows us that at 74Hz there is a delay in the buildup of energy of more than one-tenth of a second. This would certainly be audible, especially with low frequency percussion sounds, and seems like it could sound like the mushy bass that we heard.

Taking a look at the left and right spectrograms to be sure nothing has been missed, note that the frequency scale on the next four spectrograms is different from the previous plot.

Left speaker, no room correction engaged.

Left speaker, with room correction engaged.

Right speaker, no room correction engaged. There is some delay in the buildup of energy at 74Hz, but that delay is less and the peak amplitude is lower, but this is not as severe as what we have been looking at.

Right speaker, with room correction engaged. The problem is definitely at its worst with Dirac correction engaged. You could say that Dirac Live is simply doing its job increasing the gain at 74Hz to flatten the frequency response.

On the waterfall diagram the problem is not so obvious, but that is because of the waterfall timescale we are using. At 300mS, the energy at 74Hz has decayed enough to get lost among the other frequencies that make up the noise floor.

Changing the waterfall time scale to 110mS, the problem once again becomes obvious. The white curved trace on top of the diagram indicates energy level at 74Hz and shows how the energy builds up gradually at that frequency, peaking at about 110mS, confirming what we saw in the spectrogram.

Now I have to see if any of this effect is present in any of the other speaker measurements, expecting it to only show up with the F328Be’s where we heard it. We did not hear any delayed energy buildup or mushy, distorted bass with any of the other speakers we evaluated, so we should not see that problem in their measurements.

Skipping ahead a little, there were no such indications in the measurement plots for the MartinLogan Expression 15a’s or for the Adam A7X’s. The measurements for the JTR Noesis 210’s, however, are another matter. The reader will recall that the positioning of the F328Be’s and of the 210RT’s were very close to the same.

Here are the raw frequency response plots for the left and right 210RT. There is that dip at 74Hz again.

And here are the raw (Green) and partial corrected (Blue) and full corrected (Orange) frequency response plots for the left speaker.

With smoothing reduced to 1/48 octave, like we did above, the gain difference between uncorrected and corrected at 74 Hz is more obvious.

Zooming in for more detail…

And turning again to REW trace arithmetic… There is 6.5dB of extra gain at the frequency in question. This is a power increase of greater than 4X, but the 210RT is a significantly more efficient speaker than the 328Be, so the power delivered from the power amplifier at this peak would still be very low, no more than a few Watts worst-case.

The left (Green) and right (Blue) group delay plots show the same increase in delayed peak energy for the right side.

And again we see the group delay being slightly worse with room correction engaged.

This is the right speaker spectrogram with room correction engaged. Now this is getting weird. At 74Hz, we see the same group delay and the same peak energy level that we saw with the F328Be. That means it had to be a speaker interaction problem at that location in the room. And according to these measurements, it should have been as audible with the to 210RT’s as it was with the F328’s. As I recall, however, the problem became apparent with the F328Be’s immediately, and we all listened to a lot of tracks with the 210RT’s and never had any indication that there was a problem like this in the bass.

The right waterfall with full correction and a 300mS time scale. The problem does not look so bad here.

But, just like with the F328Be, looking at the 110mS time scale the delayed energy buildup problem stands out like a sore thumb.

Sonnie and I discussed all of this at length by way of a phone call one evening, with Sonnie in his home theater trying to identify anything about the room that could explain what we heard vs. what we were seeing with the measurements. Unfortunately, without hauling in and setting up speakers and listening again and taking more measurements this is as far as our investigation would be able to take us.

Possible explanations:

• The delayed energy buildup that we see in measurements with the two speaker types in question is not audible, and is not the bass problem that we heard with the Revel F328Be’s when we were setting them up.
• The measured delayed energy buildup is what we heard, but for some reason we could hear it easily with the Revel F328Be’s and could not with the JTR 210RT’s. It is possible that the offending phenomenon was never triggered by sounds in the tracks we listened to with the 210RT’s.

We decided to share this data with our readers, showing how much valuable information is buried in these REW measurements, although in this case it leads to no satisfying conclusion. To borrow a line from a favorite movie, "It's a mystery."

 

[AudiocRaver]

JTR Noesis 210RT Tower Loudspeakers

The JTR Noesis 210RT is a 3-way floorstanding loudspeaker featuring an ultra high-end, dual-concentric Neodymium compression driver with annular diaphragms mated to a wooden horn with a 60 x 60 coverage pattern. Two 10” woofers in a vented enclosure cover the frequencies below the 500 Hz crossover.


Wayne's Comments

On our way to Sonnie's place, we stopped at the JTR facility in South Carolina to pick up this pair of Noesis 210RT speakers for our evaluation. They fit in the backseat of our compact rental car with ease, as foreseen by Jeff Permanian, JTR’s president and designer. The 210RT is the smallest of his floor standing home theater speakers, and ease of transportation was a factor in selecting the pair for our evaluation get-together.

While there, I asked Jeff if it was alright if I reviewed the 210RT’s from the perspective of possibly converting a MartinLogan lover from electrostatics to compression tweeters. He said, "Of course," as a speaker designer confident in his wares would tend to do.

I have heard Jeff's Reference Tower (RT) designs in different environments over the last several years, at audio shows, in his home, and in a home setup. The Reference Tower nomenclature makes it clear that he is setting his sights squarely upon the two-channel listening crowd, as well as on the home theater buff with two-channel interests. With each design iteration that I heard, starting about five years back, it was clear that he was already well within the ballpark and nudging steadily in the direction of that goal. There are models to choose from with bigger bass drivers and with higher efficiency, but the key to transparency always lay with the concentric annular compression driver, the 60° x 60° horn (the same one is used in most models of the home loudspeaker line), and the crossover. It is the improvements made in these areas that have turned the RT’s from great home theater speakers into truly solid two-channel speakers. Over time, any sonic "rough edges" have been smoothed and soothed away until all that remains is music. That does not mean that Jeff will not continue to make Improvements. The 210RT’s we were carrying in the back seat included subtle improvements in the horn and in the crossover.

The highest compliment that a good horn design can receive is that it does not sound like a horn. This is a goal apparently not easily achieved, from the number of horns that sound like horns that crowd the loudspeaker marketplace. In my opinion, Jeff has achieved that milestone.

Knowing all of this ahead of time, I was predisposed to like the 210RT’s. So I set myself the goal to neutralize my expectations and give them an unbiased evaluation relative to that first question I had posed to Jeff: would I replace my MartinLogan electrostatics with them?


Listening Tests
Our initial setup position for the 210RT’s in Sonnie's room was the same position where his MartinLogan's were set up. The toe in angle and spacing were then adjusted for sharp Imaging and a spacious soundstage. The bass response was far from even but sounded correctable with some help from Dirac Live. As with the other models being evaluated, Dennis and I left the room while sunny set up the Dirac Live correction. We would be able to listen with one of two target curves both including subwoofers or with no correction or subwoofers at all.

The soundstage and imaging (SSI) were very good right from the start, but we were concerned about the amount of Dirac correction that was necessary to flatten out the bass response. So we decided to move the 210RT's to a very wide spacing hoping for the room’s side walls to reinforce the frequencies below 100 Hertz and flatten out the uncorrected bass response.

It is worth noting that compared to the total amount of trouble we went through trying to find the best placement for the Ravel PerformaBe F328Be, the 210RT was almost embarrassingly easy to set up, largely due to the horn design. Think of a proper horn design as a room eraser. The highly directed mids and highs interact very little with the room, so with careful spacing and toe-in angle, and in our case placement close to the walls to reinforce the bass response, there is not much else to worry about except symmetrical distances and angles. We were very happy with the results of this placement and that is where the 210RT’s stayed for the rest of our evaluation.

Perfect World by Broken Bells: My first impression of the 210RT is how easy they are to like and to enjoy listening through. "Simple," is the word that pops into my head, simple to set up, simple to get you relaxed and enjoying some music. This wide spacing has the 210RT delivering an extra wide soundstage, with the speakers completely disappearing in the soundstage, a SS&I must. That soundstage is even and continuous, no gaps or holes, a feat considering the wide spacing we have chosen. Most speakers (the horn is a big factor) could never give a continuous soundstage with such a wide spacing. The opening synthesizer on this track swishes back and forth with a convincing sense of reality.

I have enjoyed the 210RT’s before without room correction, and do so again during this listening session, so much that I get through several tracks having forgotten that there is no room correction engaged yet, a good sign. The high frequencies are extended and smooth, with no frequencies poking out annoyingly, and sibilance is well-controlled.

I listen through Perfect World, I Love You by Climax Blues Band, and Beyond The Blue by Beth Nielsen Chapman, without Dirac Live room correction engaged. A good pair of speakers can be, no, SHOULD be, a lot of fun without correction. A big score for the 210RT.

The same tracks with room correction engaged seem almost unnaturally smooth at first, as is often the case when engaging room correction even with a good pair of speakers. After a moment of ear adjustment, I am enjoying the room corrected listening setup with its delicious smoothness, and find the imaging, already very sharp, now refined to microdot precision. The percussion in Beyond The Blue is evened out with no sacrifice of impact, and the LF drivers never complain about the added Dirac Live gain, even during the heavier opening kick drum on Perfect World.

Don't Panic by Coldplay: The bass on this track is recorded with raw forcefulness that the 210RT’s handle easily on their own. With Dirac correction engaged, the tones play more evenly but lose none of their impact.

I Know The Reason by Mindy Smith, A Case Of You by Joni Mitchell: I feel it is with vocals that the 210RT’s best demonstrate their worthiness of being considered Reference Towers. The horn crossover is set at 500 Hertz, where the lowest frequencies of vocal parts will be handed off to the bass drivers and the high frequencies, the harmonics of those same vocal parts, will be handled by the horn’s drivers. The crossover melds these two ranges together seamlessly in a way that vocal parts, both female and male, come across with strength, clarity, and upfront intimacy. Joni Mitchell's vocals pull my heart out and then hand it back good as new and ready for more tracks. The simple acoustical instruments on this track appear extra large and well forward in the soundstage, and her voice feels like it is singing directly to me.

Hyperdrive by Devin Townsend: It will come as no surprise to those who are familiar with JTR’s designs that they can deliver crippling volume levels with ease. I will leave it for others to describe that experience, but I crank up Hyperdrive long enough to enjoy a few minutes of solid, smooth, super clean music at reference level.

One Voice by The Wailin’ Jennys: From the metal of Devin Townsend, compressed and sizzling, to the acoustical folk of The Waylin' Jennys, delicately nuanced, it is difficult to think of a favorite genre to hear on the 210RT’s. They can handle any genre as though custom tuned for it.

Sofa #1, Sofa Live, Inca Roads by Frank Zappa: Complex instrumentation and intricate arrangements are opportunities for the 210RT’s to reveal the inner detail and the subtle ambient cues inherent in a recording, characteristics often overshadowed by the listening room with a less-directive speaker design.

So Far Away by Dire Straits: Lonesome and longing, no emotion lies beyond the reach of expression by the 210RT’s, yet the delivery is always neutral and accurate,


Conclusions

The JTR Noesis 210RT might be the pocket-sized (well, backseat-sized anyway) little brother in JTR’s Noesis home audio line, but there was no sonic delivery task at which it did not excel. I never personally felt the need for the higher efficiency or output levels possible with certain of its bigger JTR siblings, except perhaps to experience demolition level volumes for a monster versus superhero movie.

Did the experience make any converts of MartinLogan electrostatic speaker lovers? Sonnie's view was that any potential replacement would have to deliver a head-and-shoulders-above obvious sonic improvement with clear cost-benefit worthiness over his MartinLogan system before he would consider going through the expense and trouble of a conversion from his 11-speaker MartinLogan based Atmos system to anything else. To his ears, the JTR’s were good, but not that good.

I will have to admit that the deck was stacked just a little bit against such a conversion, knowing Sonnie’s long-standing expectation threshold for what would be such a monumental changeover. I was already fairly sure of the answer for myself as well. There is nothing I have experienced yet that could make me give up my own four MartinLogan electrostatics. I have a two-channel area however, which is being laid out with hopes of becoming the home for a pair of 210RT’s as the main two-channel speaker pair in the not-too-distant future. Knowing the dedication level of most MartinLogan owners to their electrostatics, accomplishing such a conversion seems an uphill battle, but the 210RT’s might become a relatively easy sell as an alternate listening pair for those so inclined.

Any serious listener with an irregular or difficult room will do themselves a huge favor in considering speaker mains with compression-driven horn-loaded mids and highs. The room erasing capability of a good horn design is difficult to describe, and from all I have heard, an in-home trial (JTR has a 30-day full money back guarantee) seems likely to lead to permanent ownership of a pair of JTR Noesis speakers. MartinLogan electrostatic lovers, look out. I foresee some reworking of budgets and breaking of piggy banks to work in a pair of JTR’s like the 210RT’s in ADDITION to those beloved electrostatics once the choice is appreciated for its sonic possibilities. Simple.


Sonnie's Take
The first time I heard JTR speakers was several years ago at Axpona where Jeff had a huge movie system setup. So, until now I haven't been able to hear his speakers in a dedicated two-channel room similar to mine. I was more than excited to learn that Jeff was willing to allow us to evaluate a pair of his Noesis 210RT speakers in my room. The speaker design is something relatively new to our evaluations. We've had Klipsch and a few other horn speakers, but nothing this large with this exact design. The 210RT's were extremely easy to setup, not picky at all about placement, as long as you had the toe-in set properly. We initially had them about 5ft from the front wall and about 4ft from the side walls, which is typically where we begin testing placement for most speakers. However, the bass rolled off a little too much being so far away from boundaries, so we moved them closer to the side walls and were able to improve the bass response without affecting the soundstage and imaging, which speaks highly of their design. I suspect a good portion of owners would be fine without a subwoofer to pair with the 210RT's, as they were really good down low. While I enjoyed them immensely without the subs, there were a few songs where I would prefer to have the subs playing, thus my personal preference would be to add a sub for that last octave of bass if you play much music with the lower bass notes. The 210RT's produce a huge soundstage, and imaging was excellent. This is the closest I've come to having a speaker in my room that could satisfy me to a point I would almost be willing to give up my stats. I suppose I have that electrostatic bias going on that won't allow me to let go of them. If I were comparing the cost of each it would be an easy decision, as the 210RT's retail for less than a quarter of 15A's. The 210RT's are a serious bargain to say the least. Perhaps the 215RT's with the larger horn would get me closer to the 15A's... and maybe one day I'll get a chance to hear those in my room. The 210RT's are a wonderful speaker to listen to for hours on end and I enjoyed every minute I was able to spend with them. Jeff has indeed designed a remarkable speaker, and it is worth repeating that they are a serious bargain. I wish I had another room so that I could have two different listening rooms, as I know for a fact I would thoroughly enjoy a room with a pair of 210RT's soothing my ears for hours on end.


Dennis's Impressions:
I've heard a LOT of JTR product and own the last generation of the Noesis 210 Reference Tower, so I am very familiar with this brand, too. This latest version features a softly-sculpted horn mouth and a mild crossover massage. When we put them into place, I immediately recognized the sound. We played with the positioning, trying to get the bass right before settling on using the corners for boundary reinforcement. All the while, the soundstage and imaging played a starring role, as it is almost impossible to not get that from JTR.

I like to use Mudvayne 'Happy?" partially for its portrayal of the trap kit, something this drummer appreciates. As should be, the JTRs set them back of stage, the individual percussive pieces easy to place in space and time as the drummer works around the kit.

Little Feat "Spanish Moon (Live)" has the drummer using his hi-hat almost as lead instrument shortly into the intro, playing it softly. One does not have to listen intently to catch this pianissimo subtlety with the JTRs. The lead singer is placed oddly right of center in this track and was placed there when listening in this room, the other accompanying instruments scattered across a nice, wide stage, a 'feat' (pardon me, I couldn't help myself) achieved without stretching the images out of proportion. It just sounds like you are sitting closer to the stage, as should be.

Ram Jam "Black Betty" has that "live sound" edge to it, which was preserved. We kicked in the subwoofer preset, but I was unable to hear the difference and had to cheat, shining a flashlight on one of the sub cones to see if it was moving or not. It was! I couldn't tell the difference from having it or not with this song.

Over all, the 210RT made good account of itself. Precision is the key and the key difference between JTR and most others, the distortion of the high-end coaxials so low as to bring the program material forth like few speakers can. It wasn't quite up to the scale in the lower registers of the largest participant of the evaluation, but it is easily the largest value, costing considerably less than the other full-sized floorstanders, all the while worthy of playing, as well as competing solidly, on the same field. I suspect that given more time to experiment with positioning, they'd only get better.


JTR Noesis 210RT Tower Loudspeaker Specifications

• Enclosure type: Front ported bass reflex
• Frequency Response: 38 Hz - 24 kHz +/-3 dB
• Nominal impedance: 4 ohm
• Sensitivity: 2.0 V @ 1 m = 95 dB
• Dimensions: 43″ H x 12.25” W x 16.5″ D
• Weight = 125 lb

Manufacturer Direct Price = $6,398.00 per pair


Measurements
All measurements were taken at the Listening Position (LP).

Left and Right Uncorrected Frequency Response (FR)

Left Speaker FR: Uncorrected, Partial Dirac Correction, Full Range Dirac Correction plus subs

Impedance and Phase

 

[AudiocRaver]

Adam Audio A7X Powered Near-Field Monitors

The Adam Audio A7X is a 2-way powered Nearfield Monitor featuring an Adam-exclusive X-ART tweeter driven by a 50 W class-A/B amplifier and a 7-inch woofer with carbon/rohacell/glass fiber cone driven by a 100 W class-D amplifier. The crossover frequency is 2.5 kHz. The A7X’s 150 watt rms / 225 watt music drive power ensures available output SPLs per pair at 1 m above 114 dB. The X-ART tweeter is Adam’s version, with material and geometry improvements over the older Heil Air Motion Transformer (AMT) design. The AMT has long been high on my list of favored tweeter types to watch for in a speaker design, usually offering smooth, transparent high frequencies. The small faceplate area with beveled tweeter area aiding HF dispersion, along with the close spacing of the two drivers, makes the A7X a virtual point source loudspeaker.


Wayne's Comments
Our aim was to test the A7X's as serious 2-channel speakers. They are designed to take on recording studio mixing monitor duties at price and performance points that make them "high end" for home studios, while not quite pressing all the needed performance buttons to become a "reference level" mixing standard in bigger production studios. Monitors that have earned that right tend to cost many times the A7X’s price. The $1500 per pair price for an A7X pair makes them an excellent choice for the task of helping nudge a home theater owner into the 2-channel listening world with minimum discomfort. At least this is what we hoped to find in evaluating the Adam Audio A7X.

We hear the A7X referred to as a near-field monitor, but what do we mean by "near-field," and is that even the best term to use for this type of speaker? An online search for clarity will require some deciphering, as there are multiple definitions of the term, even examples of conflicting authoritative definitions. Here is my best nutshell on the matter, with a mind open to correction.

In this context, with a small bookshelf sized speaker housing two or three closely spaced smallish drivers, it is more accurate to think of the application as “free field,” the region where the sound from the various drivers is well integrated over the frequency range critical for optimal soundstage and imaging (SS&I) (250 Hz and up?) and advances with consistent frequency and phase response as a planer wavefront with SPL decreasing by 6 dB for every doubling of distance (following the inverse square law), but still close enough to the source that there is little to no audible interference from the room's reverberant, diffused field. Whew.

Clearly, the smaller the speaker face and the closer the drivers to each other the better, coaxial being the ideal, and the larger and deader the room over that frequency range the better. So, a near-field speaker is one with a small enough face to allow a listening position (LP) close to the source in the free-field region, where the listener can hear the program material directly from the loudspeakers without that dreaded diffused-field reverberation that Schroeder had so much to say about. What the listener hears is the SS&I detail inherent to the recording. Large tower speakers found in most home theaters do not allow this possibility. Near field monitors also allow the option of a more distant LP where the room's diffused field can enhance the SS&I, adding depth and spaciousness to the soundstage. This more spacious diffused-field room-enhanced SS&I listening experience is definitely our own preference, given the option, over an inside-the-recording free field listening experience.

For about an hour, the A7X pair went through a series of moves, first broadly looking for a sweet area, then in finer increments seeking the perfect sweet spot. We started with an approximate equilateral triangle arrangement spacing them widely and 8 feet or so away from the LP. I am embarrassed to report that I wrote down no physical measurements. These attempts had the A7X’s performing as far field or diffused field monitors, with the LP located in the diffused field of the listening room, weak though it may be in such a well-treated room.

The imaging was pinpoint sharp, and the soundstage was, well… very nearly perfect, but not quite. To elaborate, my favorite soundstage testing tracks include Trouble With Dreams by Eels and Todd Rundgren’s Compassion, both tracks including widely scattered arrays of sampled glockenspiel. The high tinkly bell-like sounds seemed almost to explode into the air of the room like fireworks, with a brightness that threatened to overshadow the main instrumentation of the track, but held back just enough to show that it knew its place, and JUST bright enough to show off a little and hint at good things to come. The soundstage was huge and had wonderful depth, but sadly it was not able to come together into a single continuous, seamless entity like a proper soundstage should. It was chopped up into large sections that never quite fit together, a poorly designed toddlers puzzle that baffled and frustrated rather than satisfying.

After a number of setup moves attempting to conjure a solution, our efforts were starting to echo our failed attempt at finding the perfect positioning for the Revel speakers a day earlier. In fact, we had about given up and started to set up the MartinLogan electrostatics that called the room their home, when my disappointment drove me to give it another try, pulling the speakers in closer to see if we could find a solution with a free-field position. We got close, but as they say, close only counts in horseshoes and hand grenades, so we were left stymied. The soundstage remained in sections that never quite flowed together as a single unit, to our disappointment.

Bass response, without subwoofers, was admirably strong, making the A7X seem larger than life, and the LF and lower-mid quickness and clarity were good, although not stellar.

I liked the mid-range. It was clear and somewhat forward, allowing good access to inner detail. Highs were smooth and clear, a testament to Adam's rendition of the AMT. I wished for better SS&I performance results so we could justify spending more detailed evaluation time with the A7X. But that is the performance checkbox upon which the rest of the evaluation hinges, so my brief eval report is a result of fairly brief impressions formed from hearing just a few tracks as we adjusted the A7X position.

Conclusions
The Adam Audio A7X might perform admirably in its intended environment and application. With our emphasis on SS&I being paramount, however, I am unable at this point to recommend it as a speaker for breaking into two-channel listening. If we could have gotten to the SS&I performance with the A7X to settle down to a contiguously spacious soundstage, I feel that the a7x might have fared quite well giving a more detailed evaluation. Others might find them to work very satisfactorily for their use, this is simply a report of our findings for our test environment and conditions.


Sonnie's Take
I have wanted to evaluate a pair of nearfield speakers in my room for several years now, and we finally had the opportunity with the A7X powered speakers. When we initially set them up, we placed them nearfield at about 50-inches from our ears and experimented with the toe-in until we got them where we thought they would be good. The problem was that part of the soundstage was imaging too deep. We could hear sounds from the speakers, and sounds deep in the soundstage, and it sounded detached. Dennis read where someone called it "disjointed", which describes it well. I'm not sure how recording engineers that have their speakers setup out in the middle of a studio would deal with this rather strange anomaly. It makes me think the A7X are not truly nearfield, but then again, I'm certainly not qualified to question the intent of the manufacturer, nor do I know much about studio setups with nearfield speakers, and we did not investigate any further into the issue, nor attempt to resolve it if it could be resolved. There could very well be a lot more going on than any of us were aware of. The good news is when we moved them closer to the front wall, the soundstage and imaging came together rather nicely with a very smooth sound. While these might have enough bass if setup on a desktop near a wall, I would definitely prefer they have subs, and when the subs were in the mix, I was quite impressed that such a small speakers could produce a nice sized soundstage and very good imaging. If you don't want to have to worry with amps, need a smaller system, have a small room, or want a desktop setup, these should definitely be considered.


Dennis's Impressions:

ADAM is a brand that, while not completely well-versed on their products, I am not wholly unfamiliar with, having heard several fantastic examples of their consumer products at various shows. The ADAM A7X is an audio "production" tool, typically used to create the sounds that will be "reproduced" on the consumer end, our application here. It has a few tricks up its sleeve to help with differing environments, most interesting is boundary reinforcement compensation, which we did not need in this application, but could prove helpful when used next to walls in smaller workstations. We played with that and the shelf filters, deciding on leaving everything flat. Eager to hear what a powered monitor could do "reproducing" audio in a full-on dedicated listening room, into the chair I sat.

V-shaped soundstaging was the bug bear here, with images segmented into 3 different parts. The middle/center segment had a wonderful sense of depth. The left and right segments were presented far forward of the center, causing the stage to sound disjointed. The frequency balance, highs to low were fine, sounding really good in that regard. The problem was a discontinuity between these segments and the presentation of only three imaging avenues, with all images divided up and fractured up into one of those three avenues. It as an odd experience.

Bryan Adams "Run To You", at the 1:20 mark, originate from the center, then pan gently right. In this instance, they went from recessed center to panned-in-your-face right, rather than panning on the same recessed plane it came from.

Listening again to Kill The Noise, Feed Me "I Do Coke (Snort and Leisure Remix), I noticed that increasing the volume brought the center segment/images forward, decreasing volume caused them to recess back onto the three-part stage, the left and right segment/images maintaining the same in-your-face presentation no matter the level.

The ADAM AX7 has great frequency balance, not favoring any part of the sound spectrum any more than others. I could hear a lot of potential, but for some reason, we couldn't find the right placement that would bring room equilibrium enough to calm the forward-sounding outer L/R "segments", or fill in the holes between the three L/C/R segs.


Adam Audio A7X Powered Near-Field Monitor Specifications

• Enclosure type: Front ported bass reflex
• Frequency Response: 42 Hz - 50 kHz
• Nominal impedance: n.a.
• Sensitivity: Variable
• Dimensions: 13.5" H x 8" W x 11" D
• Weight: 20.3 lb

Retail Price = $1,499.98 per pair


Measurements
All measurements were taken at the Listening Position (LP).

Left and Right Uncorrected Frequency Response (FR)

Left Speaker FR: Uncorrected, Partial Dirac Correction, Full Range Dirac Correction; Full Range Dirac Correction plus subs

 

[Jack1949]

Wayne,
Thanks for your detail analysis of these speakers! I've been looking forward to this since you guys announced the get together in July. Sounds like it was a fun time with some great speakers and equipment in Sonnie's HT room.

 

[JStewart]

How could I have missed this thread earlier?
Got me some good reading to do!
Thanks Sonnie, Wayne and Dennis for putting this all together!!

 

[tesseract]

Thanks, guys. Stay tuned, my impressions are on their way!

 

[AudiocRaver]

We had loads of fun, like we always do, and thanks again to Sonnie for hosting.

Obviously, we hoped for better with two of the models, especially the Revels. Dennis has comments on the way soon! Again, the models evaluated were:

• MartinLogan Renaissance 15A Electrostatics
• Revel PerformaBe F328Be Towers
• JTR Noesis 210RT Towers
• Adam A7X Powered Near-Field Monitors

Thanks to all for checking out the GTG results.

 

[JStewart]

Think of a proper horn design as a room eraser. The highly directed mids and highs interact very little with the room,

IMHO a key point in Jeff's (JTR Speakers) horn design that achieves this vs. some others, is the resulting comparatively narrow directivity.

Here are a couple of charts to illustrate:

This chart is from Matthew Poes review of the Noesis 212 RT that uses the same drivers and horn as the 210RT found here:

JTR Noesis 212RT Review and Measurements

JTR Speakers is a small American-made speaker manufacturer based in Wisconsin. JTR sells high-end custom home theater speakers as well as a line of pro-audio speakers. All of JTR’s speakers rely on either waveguides or large coaxial drivers, the smallest of which is 10”s. As a result, it...

www.avnirvana.com

This chart illustrates the direct sound SPL is approx +/- 30 degrees and is down 20db from there at approx +/- 50 degrees from about 1kHz and up and narrowing directivity starting at approx 500Hz.

This next chart is for a JBL HDI 3800 which is also has very well controlled directivity and is from Erin's Audio Corner and found here:

JBL HDI-3800 Floorstanding Speaker Review

JBL HDI-3800 Floorstanding Speaker Review

www.erinsaudiocorner.com

Here the direct sound is approx +/- 40 degrees but does not get 20dB down from there until approx +/- 100 degrees.

It's debatable which dispersion pattern, and hence the level of sidewall reflections, would be preferred in different rooms, because as Dr. Toole wrote, sidewall reflections can be perceived as added spaciousness. If you need to place the speakers near a sidewall though, the JTR will keep a lot more energy from bouncing off of it which will improve perceived image sharpness.

So while your preferences and mileage may vary, I have a small room and the speakers are only 14" from the side walls (and toed-in to cross in front of the MLP in a time-intensity trading set-up). The JTRs image extremely well without the use of 1st reflection absorption despite their proximity to the side walls. They also provide a large sound stage and oodles of mid-bass. Very happy with them.

 

[AudiocRaver]

Super, sounds like they are perfect for you!

 

[JStewart]

Super, sounds like they are perfect for you!

There are, thanks!
I think sometimes folks might not consider them for a smaller room when in fact they are a great choice!

 

[tesseract]

@JStewart , I also have a small/medium-sized room and am about 16" off the sidewalls, in my last home and my recent, latest space.

I very recently tried the time-intensity trade off with the 210RTs and... WOW! That helped so much with off-axis listeners/viewers, without impacting on-axis as much as I would have thought, having tried this with other speakers.

 

[tesseract]

My impressions are up for three of the four. 15A on deck.

 

[Sonnie Parker]

I thought I would post this and hopefully clear up any potential negativity anyone might get from viewing this regarding using these for two-channel listening and for anything other than home theater. Several owners would wholeheartedly disagree with Erin here... and even know a few that gave up their ML speakers for these. I like Erin... great fellow, but to suggest that no one would be buying these for two-channel is just plain wrong.

Please make sure you listen to these in your room because that will be the most significant factor in determining whether or not they are right for you in a two-channel setup, not what I say or any reviewer might have to say. Other influences will be your ability to get the proper placement for two-channel listening. Equalization, such as Dirac Live, can also be a huge factor in fixing room influences.

Giving Erin the benefit of the doubt, he does appear to have a pair that is different than what we had, which was previous to his review, and also different than what I see on the JTR website now. While the woofer drivers appear to be different, I'm not sure if the waveguide and crossover that we had are any different than what he had... perhaps, but still, I can't see that making enough difference to cause them not to be given the opportunity for two-channel listening. I would never tell anyone that you shouldn't buy a particular pair of speakers or that a particular speaker is not really designed for two-channel listening based on what I heard before attempting to rectify any issues I heard. We also have to consider the fact that everyone has different ears, different rooms, and different placement options with different equipment, and the issues that he had can, in most cases, be easily overcome and eliminated by several methods, creating a spectacular speaker for two-channel listening.

Toe-in can affect the sound of any speaker and is recommended by many manufacturers. I would caution in suggesting that a speaker is bright before attempting to fix it with proper placement and toe-in. It can be easily resolved if you have Dirac Live, PEQ, or similar. People hear differently and may very well like a flatter top end with what they consider more detail. This is all preference, so what might be considered bright to some can certainly be a good thing for others and described as smooth. As we've tested dozens of speakers in my room over the years, on many occasions, I thought the target curve we were using created a slightly bright sound. Despite having some hearing loss at higher frequencies, I still prefer a slightly down-tilted (roll-off) on the high-end, but maybe not as much as some target curves I have seen. Preference is significantly personal.

The pair of 210HT speakers we had were the closest speakers to ever compete with my MartinLogan speakers, including the 15A that I have now and had at the time we evaluated the 210HT. That is just how good we considered the 210HT speakers to be for two-channel listening. I would describe these as superb options for two-channel listening. We all agreed they were excellent speakers for two-channel, and one of the easiest speakers we've ever had to place in my room, and as Erin did alude to, easily adjustable with EQ if you have any sort of issues.