ef37a wrote:""It'd be like a guitar with only USB output."
Well, there are microphones like that CS! AFAIK most synths that have a USB port only transmit MIDI and data dumps? Only the more upmarket models output 'audio' on USB as well. OP has not I think given the model of his synth but if it is sufficiently upmarket to have USB audio (and it may be a full blown interface to boot?) it is likely to have a S/PDIF output? Pretty sure the 18i20 will have S/PDIF in or at least able to configure an ADAT port for same?
If JUST USB the only solution I can see is to do what my son did, commandeer an old laptop as the converter. If he wants better than the laptop sound card cheaply the Behringer UCA 202 is not at all bad and gives a spare headphone output.
I think the conversation threaded off the OP and we are discussing Nigel's issue on getting "other channels" into the DAW from his synth.
N i g e l wrote:The synth has basic analogue stereo in & out but the other channels are only accessed over USB.
I too would think that output-over-USB-only would be something limited to entry-level models (which is what I stated).
But Nigel, who certainly knows more about synths than I (by way of actually using some :D) seemed to imply that even higher-end synths may present certain information expecting to be the unique computer interface and not working with other regular digital audio/midi interfaces. Hence my surprised metaphor.
And yeah using a different computer as a converter would definitely do.