Are you an Okto Dac8 pro owner?
Have you tried the unit with a RPI4 personally? If so, I would love to know what OS you use, Linux, Ropieee, etc?
I have since done a little investigating via google and with Okto users in Australia.
Creating an active crossover appears to be possible within Roon using either Procedural or Convolution filters. It would be great if Okto provide a guide for this.
Reviewing Procedural EQ within Roon, the feature provides a quick and easy method of applying EQ/crossovers to multiple independent/group channels, as well as a mix routing option if needed.
Reviewing information on Roon Convolution filters, it seems third party software like Audiolense, REW, Rephase needs to be used to calculate your filters (Crossover, Delay, PEQ correction, Phase etc) utilising speaker and room measurements via microphone. These filters are then imported into Roon (via a zip file) which sets your crossover, filter correction and routing.
I agree the Okto Dac8 pro provides a basic I/O matrix, but for an active speaker setup whereby DSP crossovers are applied in the PC, I don’t think this particularly helps. Unless of course you have multiple channels using the same processing input. Signal processing/routing needs to be completed in the Roon environment, in order to provide discrete equalised channels for output.
As for performing filtering inside the Dac8 pro, this is not what the units documentation states.
The unit is a Dac only. The only filtering selection on the Dac8 pro, is the filter reconstruction settings.
7 filters are possible. https://www.oktoresearch.com/assets/dac8pro/DAC8PRO_owners_manual.pdf
These are not crossover filters.
But I agree the XMOS would be used to pass bidirectional audio across the USB connection, inline with your connections and application.
It would be great to hear from Okto Dac 8 pro Roon users with Active speaker setups, explaining their setups, and required configuration.