Hooking up REW/UMIK-1 in 2-channel system

[DSK]

Hello everyone.

I've just received my UMIK-1 mic and have downloaded REW on a laptop. My 5m double shielded USB cable (to hook laptop into my system) should arrive in the next day or two.

My system is a 2-channel music system (NAS > Streamer > DAC > pre-amp > power amp & active Sub) but the REW guides I have scanned so far seem to be aimed at A/V systems which connect the laptop running REW to an AVR via HDMI or the headphone/mic output.

Am I correct in assuming that I can simply run a USB cable from a USB output of the laptop to the USB input on my 2-channel DAC and use the pre-amp for volume control? Anything I need to be aware of, would I need to load a driver on the laptop for the DAC (I haven't previously used the laptop as a source as I prefer not to have a computer in the listening room)?

My goals are to:
1) see if I can improve the subwoofer integration by measuring Left + Sub and Right + Sub (the sub is connected via stereo Left/Right SE cables from the second pre-amplifier output and sums them at the sub input) ... I'm pretty happy with the LPF XO and Gain settings on my sub but using sixth octave tones and a a Rat Shack SPL meter I haven't been able to identify any changes through the crossover region when adjusting the Phase dial. REW should make this easier.
2) identify whether there are any significant peaks/nulls in the crossover region or above that could be improved by adding something like a miniDSP Studio into the system to take on HPF/LPF duties and perform room correction via Dirac and PEQ.
3) determine the RT30 of my listening room before adding any additional absorption/diffusion

Any tips/links from those who have been down this path would be very much appreciated as I'm completely new to REW.

 

[Wayne A. Pflughaupt]

It’s best to use the recommended connection schemes, as they are known to work. Anything else, you are the guinea pig. Let us know how it works.

Regards,
Wayne

 

[DSK]

Thanks Wayne.

Are you saying that the USB method I proposed is not a standard/recommended method to hook up REW on a laptop to a 2-channel music system?

As such systems don't have an AVR and typically don't have an HDMI input anywhere, that would seem to preclude the use of REW in non-A/V systems ... unless the intended approach in these systems is to use the headphone/mic output of the laptop into a splitter then into left and right analog cables that then plug into a single ended input on the pre-amp?

I know that it is common for a laptop to be used as a music source via USB into the DAC in a 2-channel system (not sure about whether a driver needs to be loaded for Windows) so I'm confused as to why REW wouldn't be able to send its sweeps/impulses to the system in exactly the same way.

 

[ddude003]

DSK, sure... Why not... Just try it and see if USB works... You might also try connecting to your streamer via UPnP...

I have gone direct to my DAC via usb and via my streamer (Lumin U1 mini) via UPnP from my MacBook Pro... Note that timing may be off a little if connecting to your streamer via UPnP across a wired or wireless network... Mac did not need any special drivers... On Windoz you may need an ASIO driver... I don't know if your DAC will need a special ASIO driver from the DAC manufacturer...

 

[StrokerAce]

Have you had success with this yet? I am trying to do much the same thing but only with 2 subs and an integrated amp. I have used USB from my integrated to my laptop as my output and the Umik1 as input. I'm not real sure of where to go from there though. Do I need to change soundcard setting in my laptop so that it's using the integrated? I would imagine that to be the case. Hope you see this post and I can't believe you didn't have much response from other members. Can't believe I can't find much info at all when it comes to 2 channel verses home theater.

 

[John Mulcahy]

2-channel systems are generally straightforward. If the system has an analog input drive it from the computer's headphone output and pick that as the output in REW. If not and the system has a DAC you can drive from the computer over USB, use that and pick it as the output in REW. If neither is appropriate you can use file playback, in the same way as any other file would be played on the system.

 

[StrokerAce]

Alright. Since I'm talking to the man, I will be a bit more specific. I have a Parasound Hint 6 that has a USB input. I am running two REL subs out via low level RCA. I want to get my subs level matched to the mains spl. My mains are Dali Opticon 8. After I get subs level matched, I would also like to take some measurements for the subs alone, the mains alone and then the whole combined.

I have a Umik-1 and I had purchased a DDRC-24 miniDSP unit based upon their recommendations for what I have. Unfortunately, the unit they recommended wasn't compatible as I have an integrated; even though I told them beforehand I had an integrated.

As I am unable to run any kind of room correction, I want to get my system set up through speaker placement based on measurements and sub integration. I'd like to try to get my crossover settings set based on sub and speaker roll-off.

I have had it set up previously so that I was able to play test tones from REW through the Parasound via my laptop. Eventually I kind of gave up because I had to chase so many rabbit holes that I didn't have time to follow at the time. I am running Windows 10.

 

[John Mulcahy]

I see the Hint 6 has a "Theater bypass amp input", could the DDRC not have fed that with your source connected to the DDRC?

You could use the USB input from your computer or use an analog input to send the measurement sweeps. You will need to manually disconnect (or switch off) the subs or mains to measure them in isolation if you use the Hint 6 sub crossovers.