Demastering your music

[DanDan]

One of our top Mastering Engineers:-
Elysia NVelope - another fabulous tool. I'm quite impressed. But so much power ---- If you're the mastering engineer, you can seriously change the mix engineer/producer's intent: use it wisely!
One hint: Work it in MS: I think gives you more flexibility than L/R mode.

 

[Chris A]

In the meantime, do you have a shortlist of classical recordings that need little to no rebalancing?

I think it's a much shorter list to identify those classical recordings that I've demastered. I'll see if I can update my list of classical albums I've re-EQed from the posted list in 2000.

Many older classical recordings have HVAC infrasonic droning fan noise issues and their harmonics, as well as 60/120 (North America) or 50/100 Hz common mode noise bleeding through one or both channels.

The solution that the record companies used to employ to handle that deep HVAC fan noise in decades past (before CDs were introduced in 1983) was to simply attenuate the bass, starting at ~450 Hz--the nominal break frequency of older preamps having bass and treble tone controls--and progressing at -3 (or even as much as -6) dB/octave into the lower pass bands.

When you EQ the bass back to a more reasonable music curve reconstruction while looking closely at the revealed background noise to help guide the restoration of bass, you reveal old HVAC fan noise issues again. Those low frequency noise sources act as added opaqueness of sound quality. When those narrow and deep bass HVAC noise bands are notched out, the entire recording sounds audibly more transparent. I can't tell you how many older classical recordings have this issue--but it seems to be on a majority of older released phonograph recordings.

[Apparently, most hi-fi enthusiasts got used to listening to their classical recordings--but without any bass. Piano recordings always gives this away most audibly--since the left hand fundamental frequencies simply disappear--no longer sounding like a real piano. Pipe organ recordings (Bach, etc.) used even more pronounced bass attenuation slopes: I've had to employ more than 20 dB of total boost at 20 Hz to restore some of those old pipe organ recordings from analog tape sources.]

Chris

 

[ddude003]

I hope I answered some of your questions (some are anticipated questions). Did I?

Thank you for this explanation of what you are doing... I, and i'm sure others, appreciate this additional information as an addition to your other documented information...

As I have converted to streaming highest quality Qobuz, hardly ever listening to my local digital files, I am mostly looking at various signal chains I can stream thru... What I have now has already taken my AV NIRVANA to the next level...

 

[vincenzo_uli]

@Chris A I’m interested in hearing your thoughts on Prof. Johnson's reference recordings. I particularly enjoy "Mephisto&Co." with Eiji Oue and the Minnesota Orchestra. Do you think there's any room for improvement with the re-EQ technique?

 

[Chris A]

I have a collection of Prof. Johnson's recordings, but that one I don't yet have (but may order it soon based on your comments).

Of all the recordings of his that I do have, I'm not sure that I can do anything to improve them. I can certainly change them. The most recent Prof. Johnson recordings of the Kansas City Symphony and the Utah Symphony (i.e., multichannel DSD files on SACD) have pretty spectacular dynamic range and loudness statistics. I'd say that it wouldn't be demastering, but rather remastering if one chose to edit them.

I can enthusiastically recommend the latest multichannel SACDs from Reference Recordings. Johnson's recording of the Kansas City Symphony playing the (somewhat notorious-from a recording perspective) The Planets is a real treat, as there are no sections of this recording that sound "loud" (I'm speaking mostly on the leading movement Mars-Bringer of War) like all other recordings that I've heard or own. I have some theories as to why this is so...and multichannel (5.1) is one of those reasons, another being the use of a much greater portion of the dynamic range capabilities of the DSD format without any tendency to make the resulting tracks louder after the recording is made, or the use of compression during recording.

Chris

 

[vincenzo_uli]

Dear Chris, thank you so much for the suggestion. I'm actually a huge fan of The Planets, but I hadn't heard this version before. It has an incredible drive and rhythm! I also really enjoy Boult's direction with both the New Philharmonia Orchestra (1966) and the London Philharmonic Orchestra (1978). However, the recording quality doesn't match that of Prof. Johnson's. I wonder how re-EQing would affect those two recordings.

 

[vincenzo_uli]

I recall that Dick Burwen used to upmix content to 5 channels and added a form of reverberation or ambience to the sound. This product, called "Audio Splendor," also allowed for EQ rebalancing in tenths of dB. I’m curious if your approach is similar and if, in your experience, it makes sense to upmix a stereo track to multichannel.

 

[Chris A]

Well...up-mixing from 2-channel to 5-channel surround sound is something that is ubiquitous in audio today. Virtually all A/V preamps and receivers have this capability, and there have been papers written on the subject, e.g.,

https://www.aes.org/journal/sample_issue/JAES_V50_11_PG914.pdf

I would personally look to how Trinnov or perhaps Lexicon does this task. The 2-to-5 channel synthesizers used in most AVPs and AVRs leave me a little wanting. I'm told that the better quality up-mixer/synthesizers from the two companies I identified achieve better results. The problem is, this isn't free (far from it). If I find a high quality 2-to-5 channel multiplexer available as a plug-in, I'll let you know.

I've not delved into this subject with my demastering efforts, but I have demastered several 5.1 music albums using Audacity (...yes!...) but some care must be used since Audacity itself does not play back 5.1 channel music--only stereo/mono (i.e., the last time I looked). So any worked tracks must be first saved to hard disk, then played back using something like foobar2000, etc. Iterative updates to the 5.1 tracks can easily be done by undoing any operations within Audacity, then updating the settings, and then saving to hard drive again to listen to them. It sounds more complicated, but in practice, it actually becomes second nature to do this.

I can remember a couple of notable 5.1 albums that required significant demastering/declipping/re-leveling the loudness significantly downward to zero average on the ReplyGain loudness scale. A very old album redone in 5.1 DVD-A (24/96) that had significant clipped was The Who's Tommy, and another multichannel version of a Porcupine Tree (DTS) Fear of a Blank Planet had such severe clipping that they were basically unlistenable as released. With the practices that I've described above, these two albums are now a pleasure to listen to.

The Porcupine Tree album even required a spectral tilt toward the higher frequencies in order to restore the spectral balance after the severe clipping off the disc was repaired. This was the first time that I ran into an album that was intentionally re-EQed by the mastering guy to make it more listenable after clipping the tracks so severely that they couldn't be listened to as-is, and had to be EQed with the high frequencies tilted very much downward.

It's amazing to me the lengths to which mastering guys will lend their good names into doing.

Chris

 

[vincenzo_uli]

Hi Chris,

I have a practical question about the demastering procedure. I noticed that your hi-fi rig is fully integrated with your PC desktop setup, allowing you to work on demastering directly in your listening room.

In my case, and likely for many other users, the workstation is far from the listening area.
I'm wondering if it's feasible to use a pre-EQ'd headphone setup to work on tracks at the desktop, then transfer the results to a phase-coherent hi-fi setup in another room.

Personally, I'm using a pair of Sennheiser HD800 headphones with Oratory's Harman Target equalization: Sennheiser HD800 EQ.

What do you think?

 

[Chris A]

You can use headphones to get the spectral balance corrected, but note that headphones eliminate the stereo crosstalk issues (left ear hearing the right channel, and vice versa) that you get in-room with stereo loudspeakers, so the perceived "1.8 kHz stereo notch" from listening to loudspeakers in-room will not be present in the headphone listening case (a.k.a., the interaural time delay perceived notch in response that Toole talks about as "the fundamental flaw of stereo"), and the brilliance of the resulting mix might be affected when transitioning between the two cases. You'll need to factor those issues into your translation.

Additionally, room acoustic mode effects and the absence of full-body infrasonic bass perception will be missing from headphone listening, and soundstage imaging effects will be quite a bit different, with in-head imaging the largest difference in the case of headphones.

But from my own background and experience, "better is better", so anything that you can use to rebalance the tonal spectrum and hear the effects of removing clipping ("limiting"), restoring attenuated bass response, and hearing the effects of notching out infrasonic HVAC and common mode (AC electric power) noise will of course be useful. Over time and using your headphones, you will develop a better feel for how your stereo loudspeakers will sound using headphones, and how much different it will be. Only after trying it for a while will you find if the effort is worth the results.

Certainly, you can demaster music tracks for listening using your headphones, and the differences in how you perceive the music using headphones vs. loudspeakers/room acoustics will become much more apparent to your developing listening acuity.

Chris

 

[vincenzo_uli]

Hi Chris,

Thank you so much for your great insights! I really appreciate it.

I would like to discuss some more questions with you via direct messages about system configuration. However, it seems that the platform is preventing me from doing so for some reason.
Could you please check from your end if I have permission to send direct messages?

Thanks a lot in advance!

 

[Chris A]

I just found the setting that allows PMs to be sent to me. Sorry about that--I didn't know it was set to "off".

It's enabled now.

Chris