Re: sound card for digital speakers
Is that the only input for the speakers? Digital coaxial will typically be a yellow RCA port. I've seen 3.5mm (mono) to RCA cables. They are typically for the sub channel only (hence the 3.5mm mono connector), and they are NOT digital...it's an analog connection.
With that said, digital coaxial inputs AND outputs are RCA ports. If it is a digital connection and If the cable has 3.5mm connector on one end, it sounds like a specialized cable for a specific card/PC.
There are numerous sound cards available with a digital coaxial output (again, RCA port). 3.5mm jacks are standard analog stereo ports.
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