Assign output to channels other than 1 and 2 on a Mac

I am brand new to Roon and have a question that was already asked by another member way back in Jun17 but never seemed to be resolved.

I am coming from Pure Music and used to run two USB DACs out of my Mac mini (which will now be my roonbridge endpoint). One DAC would have channels 1/2 and the other 3/4. I would assign them as an aggregate device in the Apple Midi and use Pure music to set up a crossover to send the high pass to channels 1/2 and the low pass to channels 3/4 (for my stereo subwoofers). Roon seems to have the exact same capability only without the need to setup an aggregate device.

So my question is whether it is good to use Roon in that fashion? The apple aggregate device specifically sets a master clock and applies drift correction to the second DAC. Does Roon do the same when you combine two devices on the same endpoint? It doesn’t seem to give an option to set a master clock.

If it does not, I would really like to assign a crossover to my four channels in Roon using the aggregate device but it never seems possible to assign left and right stereo to more than channels 1/2.

Any advice is appreciated.

Hello @Papi_Chulo,

I apologize for the delayed response on our end. I was doing some research in the area and your ticket did not get attached to the report.

Have you tried using Roon’s DSP Engine Procedural EQ Mix settings to create custom input/output rules? To get to the Procedural EQ Mix settings, open Roon’s DSP Engine and click the “Add Filter” button. Then click “Add Operation”, and click “Mix”. Here, you will be able to create arbitrary Mix rules such as send the “1” left channel to outputs “1” and “3”, and the “2” right channel to outputs “2” and “4”.


No problem, not in any big rush.

I was able to find the Master clock priority and educate myself on how that works. Though different then I anticipated, it performs the exact function I was wondering about.

As to the “mix” procedural EQ, I was not able to execute the one channel split to two you described. I think I just need to fiddle with it until it works for me or makes better sense to me.

Thanks for the help.

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