I'm currently without a digital coaxial cable, due to giving it to my parents (for a DVD player), so I broke into my storage room and rooted around until I found my old red/white AV cable. I listened to a CD and sporadically heard static, especially during the first 10 seconds of playback. I listened for about 20 minutes, played track 1 again, and the static was gone. I then wiggled the cables and found I could control the static.

Having not listened to audio through standard red/white cables for at least 8 years, I can say there is a difference between them and digital coaxial. The music sounds "narrow" and lacks depth. I've also never heard static through digital coax (or optical).

Wait, were you using an interconnect as a digital cable, or were you just running the RCA out from the CD player without a separate DAC?  If the former, I would not expect to have that work out too well.  I tried using composite cables to make a component video connection once; it did not work well at all.

As for degradation of old cables, I think that does happen.  The copper will oxidize over time, and I can envision that messing with the sound.  Similarly, the connector will oxidize, and the solder joints may weaken due to stress.  Also, the throw-in red and white cables tend to be very cheap, and likely not up to par with the rest of your equipment.

The DAC I use is included in my HeadRoom Balanced Desktop Amp. I used to run a Monster digital coaxial cable (RCA at both ends) from my Marantz CD player to the HBDA and got a balanced signal. I gave the Monster cable to my parents, so until I get another digital coax, I am using the non-digital RCA cables. The first thing I noticed (before the static) is that they can't send a balanced signal; I had to put my amp in unbalanced mode for the first time.

I've been exclusively listening to balanced signals through headphones for the past 4 years and this may be why the unbalanced RCA cables produce such a shallow sound. I agree that they're weakened and cheap, which just makes the sound even less invigorating.

I decided to order this digital coax: http://www.thecableco.com/Product/Starlight-6

I feel it's on par with the rest of my equipment, which is mid-grade (since the price is neither high nor low).

As for improving the connection between my HBDA and PC, I decided to order this cable: http://www.headphone.com/accessories/ki … -cable.php

My HBDA is concurrently hooked up to my PC and Marantz. Both sound exceptional, but I feel the Marantz edges out the PC.

It's not clear from the entry post how the coax SPDIF cable is integrated in the playback chain.

And I partly disagree with crash. The problem (mostly) isn't the cable itself, but the connector and the connection between cable and connector (so soldering _is_ an issue). Cheap connectors don't last long if you constantly plug and unplug them. That's not limited to connectors though, also the sockets are affected.

It's not part of the chain currently. I was referring to old-style red/white cables. When I get the Wireworld digital coax (SPDIF), it will be chained between the Marantz and HBDA.

You're not using it, see below.

Balancing isn't a feature of the digital signal.

(1) You're currently feeding an analogue signal into the amp. So you're just using the amplification feature of the amp, not the DAC component.
(2) The circuitry probably can't construct a balanced signal from (already) analogue input. There are amps that can do this, but this one apparantly can only create them through his own DAC.

@audiophile USB cable: This is a scam.

I understand that. 

The balanced mode does not work with the analog red/white cables. You are correct.

I don't understand. How do you know? Have you bought the cable and compared it to cheaper priced cables?

USB is "content-agnostic". It doesn't care if you're transferring music or any other type of bitstream. That's like with any other cabling that carries a digital signal (e.g. TOSLINK or HDMI). With USB and HDMI you even have error detection/correction, something that is missing for SPDIF over TOSLINK.

EDIT: If I were you, I would be more worried about the coax SPDIF connection (ground loops, clock recovery, etc.).

EDIT2: I forgot to mention that the group loop issue of course can also happen with HDMI/USB connections. However it seems that it is more prominent in the coax SPDIF setting. Nothing you can do about it by just changing cabling though, except if you have the option to use optical fiber.

You inspired me to change my mind, which is not the easiest thing to do.

I ordered a different cable from Amazon and decided not to "upgrade" my USB cable.