Hello Doug,
Other options might be:
- MOTU 16A (
http://motu.com/products/avb/16a ), which has 16x 1/4-inch analogue audio outputs, and a second 16A can be chained (via a standard Cat6/5e Ethernet cable) to make a total of 32 analogue audio output jacks. It works via USB 2.0 or Thunderbolt (or AVB Ethernet). I have two of them and they work very well for me, on both Macs and Windows. I find their audio quality and performance (latency, etc.) to be very good.
- MOTU 24Ao (
http://motu.com/products/avb/24ai-24ao ), which has 24x analogue outputs (but you need a separate break-out cable, or to wire them yourself), which can work via USB 2.0 (or AVB Ethernet).
Doug S. wrote:Some mention SPDIF as the source of the additional outputs. I'm confused as to how one uses these digital outputs from either a single optical output or a single RCA plug. Does one have to add additional hardware to use these channels individually?
Yes -- digital outputs (S/PDIF or ADAT) require additional digital-to-analogue converter hardware in order to use them to driver amplifiers/speakers.
Best regards, Martin.
Hauptwerk software designer/developer, Milan Digital Audio.