I believe you can aggregate the two devices. You should sync the two clocks to avoid drift.
But given the choice I would avoid it. The sync between the devices is super important in your application, and you are depending on apple’s software to do this
I think a better solution would be to use a 4 output DAC that will do routing / DSP. I’m pretty sure an RME ADI-2 pro will (although one of the stereo DACs is unbalanced)l (or even better the new ADI-2/4 pro - which has 4 balanced outputs).
Then the sync issues will be taken care of in hardware /firmware.
So there are pro audio devices that support multiple digital outputs, although off the top of my head I can’t think of a single box solution.
You can find audio interfaces that provide ADAT or MADI outputs
ADAT provides 16/8/4 outputs in a single fiber at 48/96/192 kHz
MADI provides 64/32/16 outputs at 48/96/192
In the RME world, which I know best, you’d need an interface with ADAT or MADI outputs and then a digital router to split this to multiple AES / SPDIF stereo outputs.
Do you also need dsp to do the crossover between the low/hi drivers?
This is going to be expensive - so hopefully there’s a better / cheaper solution.
One other idea is that you can buy AES splitters - which split a single AES stereo signal into multiple. They are often passive with transformers - so won’t effect the timing. Do your DACs have AES inputs?
Obvious you can’t do any dsp/ crossover processing with this option.
Lovely discussion. I’m not as advanced as you are. You just tell me to shut up
I do have a hip dac, a zen dac, a 200m and tried out the aggregated. One weird think is that I cannot aggregate the first two, both devices on and os sees only one iFi. So I pulled out 200M, mow it sees 2 devies and I can connect them. I see the aggregate as a separate device in roon. If I can do more just tell me but now I have to run to work