If you have an interface with SPDIF in/out, I highly recommend finding an older rack effects unit to utilize them. Picked this bad boy up for $150 and it sounds gorgeous. :
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Roland - M-10MX | 10-Channel Battery-Powered Mixer
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Midiman SAM S/PDIF-ADAT
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RME
Rane MP2015 with S/PDIF Input and Output - YouTube
Does a coaxial s/pdif splitter/combiner exist? - Steinberg Lounge - Steinberg Forums
Best Optical/TOSLINK Out (S/PDIF) Digital Live & Studio Mixers | eBay
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Need something to mix digital audio signals together or digital and analog mix with SPDIF out - Audio Hardware & Software - Level1Techs Forums
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Midiman SAM S/PDIF-ADAT
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Amazon.com: PreSonus Studio 1810c USB-C Audio Interface 18-in/8-out with 4 Xmax Preamps, ADAT I/O, S/PDIF I/O, MIDI I/O, DSP Monitor Mixer with Gravity Magnet Phone Holder and Pair EMB XLR Cables Bundle :
