How do I measure a system with multiple output devices?

[TetraMan]

I have tried and failed to wrap my head successfully around this scenario. Can anyone point me down the right path?

My speaker configuration: One pair of 3-way towers... however, the woofer in each enclosure is wired separately and without any crossover, with a separate/dedicated pair of binding posts directly feeding the driver. The mid and tweeter share another pair of binding posts and have a 3kHz crossover inside the enclosure. Therefore, each speaker enclosure has four conductors running to it. One pair for woofer, one pair for mid/tweet. The environment includes one standalone/self-powered subwoofer with L/R inputs, variable phase control, and variable crossover adjustment.

Amplification to each of the separate tower speakers is provided by one of two separate Class A amps feeding the woofers using the Left channel output and feeding the mid/tweets on the Right channel output. As stated, the separate subwoofer is self-powered.

My AudioLense PC also hosts/runs JRiver Media Center.

There are two (2) miniDSP 2x4HD units connected to that PC via USB (for both control and audio). The miniDSP units are used primarily for their DACs (while far from perfect, they were already available).

miniDSP #1 supplies the class A amps for the pair of towers. miniDSP #1 Outputs 1 and 3 feed the woofer (left) channel on each amp. miniDSP #1 Outputs 2 and 4 feed the mid/tweet (right) channel on each amp.

miniDSP #2 Outputs 1 and 2 feed the subwoofer L/R channels.

The microphone is an Umik, directly connected to the PC via USB.

Given that the six audio channels (left mid/tweet, left woofer, right mid/tweet, right woofer, subwoofer left, subwoofer right) are not on the same output device in the PC, how do I configure AL to send the sine wave test sweeps so all drivers eventually get measured? Do I have to test/measure separately and then somehow (????) combine the results into a filter? And then there is the question of how to get JRiver Media Center to split the processed signal to the appropriate devices. One step at a time, though.

Tips? Tricks? Ideas?

Thanking you in advance.

 

[jrobbins50]

I don’t think you can do it as is. With essentially two DACs, you need something like the miniDSP UDIO-8 to combine them into a single DAC. https://www.minidsp.com/products/usb-audio-interface/u-dio8
I used to use this device to combine four Musical Fidelity V-90 DACs into a single multichannel DAC that AL XO would recognize as a single DAC for measurement and convolution purposes. JCR

 

[TetraMan]

Thank you for your input. I thought I had seen some post on the forum involving a large number of speakers/drivers (> a dozen? or was it pushing 30? I do not recall) and I assumed there would have been multiple sound devices involved in such a large system. For that reason I hoped that somehow my existing hardware would be sufficient.

You no longer use the u-dio8? Were you dissatisfied with some aspect of it? Did you use JRiver for playback? If so, was JRiver happy with the u-dio8?

 

[jrobbins50]

I can’t answer the first question but as to the second, I have an Okto dac8 pro which does my eight channels for 5.1.2 with a single DAC, so I don’t need to use the UDIO-8 device any longer for that same purpose. This said, I still use it to for a specialized application to route the USB output of a MacBook to the eight channel input on a Lynx AES16e sound card in my main PC. This lets me play out Apple Spacial (Dolby Atmos lossy) from the Mac into my PC for convolution and upscaling with HQPlayer.

I use Roon but can think of no reason why the UDIO-8 device would not work with JRiver as well. JCR

 

[TetraMan]

Your time and insights as to alternative hardware options is much appreciated, and I will look into those options.
Too bad I cannot somehow cheat and get AL to use the two DACs together.

Thanks again!

 

[juicehifi]

Your time and insights as to alternative hardware options is much appreciated, and I will look into those options.
Too bad I cannot somehow cheat and get AL to use the two DACs together.

Thanks again!

This is not a specific al problem as there are synchronisation problems with using two devices this way. It may work if then do asynchronous resampling on the input. You could e.g. try with Asio4all as the middle man.