Gee... Guess I shoulda started a new thread more specific to coaxial digital audio v/s optical.

Yes, I've seen a ground loop caused by this. My silly DVD player had a grounded cord, and when connected ONLY via Coaxial to the receiver (which is also grounded), I had a loud hum. Removing the ground on the DVD player (which seemed an odd thing to do anyway) fixed the problem.

Personally, I think there's something wrong with the receiver. :-P

That prevents the discusion from sagging too much.

This message was edited by G50AE on 11/30/03 09:52.

Any main system component that causes ground loops due to its internal contruction is inheirently defective, IMHO.

My system seems sensitive to ground loops... I can only really have things grounded at ONE place. Older DVD players no problem, but the new one with a 3-prong cord caused issues on analog or digital coax. I originally had my DSS coax run grounded at at the DSS and a connector in the middle of the line, but that caused a hum on whenever listening to DSS audio.

My spiderweb of coax cable for cable TV works fine though. :-)

Oops Daniel,

Your description of coax as lossless is not correct. Yes as you describe any length of coax maintains it's impedance (in this case 75 ohm). The reason this is advantageous is for power transfer. Without impedance matching on the output driver and cable system and input. Some signal would both reflect (cause interference) and not transfer well (power loss). But that is not so say that there is no loss in a coaxial connection. There definitely is line loss which presents itself as a loss in signal strength without a change in impedance. You still get the most signal transferred that is possible without knowing beforehand how long the cables will be. This is the design constraint the drove the creation of coaxial cable. Shorter cables will always have higher signal transfer. Not to say that that signal loss is prohibitive for even distances of 100 feet. Especially for a digital signal. You are only left with the issue of digital signal timing.

Since there's multiple Daniel's in this thread and just so it's clear, you're responding to Daniel Nguyen, whose posts are incidentally dated more than 5 years ago...

LMAO @ the Big Cheese. BTW, Thank you for kicking CB off the site. Excellent work.

coax has more bandwidth, but more opportunity to have EMI issues, I prefer coax.
toslink optical has less bandwidth, but no chance of EMI issues, but can have digital gitter issues because of toslinks poor design. ST glass optical is much better, but only found on high end gear.

Daniel, removing the ground is not a good idea(it is actually a code violation as an itegrator for me to use, on a permanent basis a ground cheater, can we say potential fire hazzard), I would suggest trying other options, such as, first check to see if all the gear is plugged into outlets that are on the same phase(not necessarly the same circuit). If part of your gear is on one phase and other gear is on the other phase then you are completing the 60Hz cycle that A/C operates on. I would call an electrician to check that for you if you are unsure on how to do that. the second option for you is to give the folks at jensen transformers a call, http://www.jensen-transformers.com/ , they make excellent ground loop breaking products, and Bill Whitlock is an absolute genius, I took his class on grounding and safe interfacing at CEDIA, and I tell you, if he does not have the answer, you will not find it. He has written more "white papers" on grounding and A/V systems than anyone in the business. Thirdly you could have something wrong with the reciever :) , If you would like help trouble shooting just let me know I am more than willing to help out the BIG CHEESE!

What a brown-noser! :-)

Everything is on the same phase; I made sure of that when wiring. I've taken that grounding course at CEDIA as well; and for the extent that I wanted to troubleshoot a DVD player I'm content to "cheat" on it until I rewire the system when I purchase a new amp.

At about the same time I solved one other ground loop problem on a satellite coax line (mistakenly grounded in two places), and for all I know that may have solved the DVD problem as well.