Being in this hobby for a very long time, I have always believed in the benefit of using high-quality cables in my setup.
However, I have introduced a new factor in the equation… USB/Pro ISL Fiber. I suppose the issue I’m grappling with is the notion that fiber has the benefit of cleaning up a signal to the point that any cable (i.e., noise) that occurs before the fiber connection is muted, which means that all the goodness a quality (or crap) cable would provide is negated by the fiber stage. The ol’ bits is bits argument!
Or are we still dealing with a situation where “crap in, crap out” is still a factor?
The ProISL fiber connection does not clean up the data it is asked to transmit. It does however completely clean up conducted noise and jitter, and prevent downstream data corruption as well. It does this by cutting the conductive path (with the glass fiber itself), forcing the data to by synchronous with the DAC which prevents jitter generation (clock feedback to the fiber transmitter), scrambling the data to get rid of downstream data correlated noise, and adds forward data correction to detect and fix any corruption on the fly.
Keep in mind that (almost) all the circuity of Pro USB/fiber is designed and built by MSB. I don’t know for a fact, but I’m pretty sure that MSB has built in error correction into the circuits. Also fiber will not pick up any EMI that is floating around in the air, like a wired connection would. So I doubt the fiber connection will result in incorrect bits.
Also, I think there is no comparison between the use of fiber for SPDIF and its use in a fiber data line. So issues we have all have had in the past using fiber SPDIF doesn’t really say anything about USB/Fiber.
You will need a short length of USB cable to connect the USB dongle to the audio source. Probably any short USB cable will be fine, though on my system I use a Wireworld Platinum Starlight USB cable, but I am all about belt and suspenders.
It looks like you will be able to listen to both a Pro USB and a digital audio connection. In he end it’s really your evaluation of the sound that decides what, if any difference there is between the two.
Yes, its this comparison between AES/EBU and Pro ISL that has forced me to ask these questions about the importance of high end cables behind the Fiber stage. MInd you I have no interest in selling off all my quality cables and investing in lamp cord!
This is really just a question that comes up when you consider where the limit of sound quality ends. Would a better USB cable make a difference? I dont know. Is my modest Cardas Clear USB cable all I need to get the most out of the system?
Anyway, I suppose (as always) this is a case of trying things out and seeing what works best with my sytems synergy.
