If the connector to the audio equipment is digital (TOSLINK, HDMI) - then does it matter at all what comes before it in terms of noise, signal clarity and sound quality?
I'd assume since all the information is digital up until that point, it shouldn't make any difference... that all the arguments flying back and forth are only applicable to analog connectors.
e.g.
[Motherboard sound output via TOSLINK or HDMI] vs [SoundCard, Video Card or external USB DAC that also connects to the audio equipment via TOSLINK or HDMI]
yeah a digital file is the same, no matter where it's stored. the quality doesnt change.
however, the device holding the digital file may add noise to the overall system, and this noise can make its way to the speakers.
additionally, cables tend to act as antennas (depending on what theyre made of, and how theyre made), which pick up noise, which makes it to your speakers (optical doesnt pick up noise, which is why people like it).
that said, in practice, it usually doesnt make a ton of difference... unless youre really picky and/or your system's really good.
but to be more comprehensive:
there's the issue of processing the digital signal.
all digital signals must be converted to analog in order to be played on speakers (which is why you always see a DAC... the Digital to Analog Converter).
Not all DACs perform the same, so the device's DAC will affect the sound quality.
then there's the issue of
which device's DAC is doing the Digital-to-Analog Conversion.
the device storing the digital file may process the file, then send it to the next piece of audio equipment.
or the device storing the digital file may simply send over the 1s and 0s untouched (called "passthrough" or "bitstream"), which ignores the first device's DAC, and allows the next audio device's DAC to do the processing.
basically if your set up has multiple DACs, it's best to know which device has the best DAC.
so it all kind of matters.
