cd player - xlr output buzzing

nifty device!!

hmm good question -- how can one test for noise floor interference?

Good suggestion by Dave about the Jensen transformers. A number of Audiogon members have reported using them, with no perceivable sonic side-effects.

There is an excellent paper at Jensen's site about interfacing balanced and unbalanced equipment:

http://www.jensen-transformers.com/an/an003.pdf

Note that among the various approaches it describes, the adapter cable approach is shown for rca to xlr input, but NOT for xlr output to rca input. Although it certainly can be done sometimes, if the output impedance and drive capability of the output circuit permits, or if pin 3 is left open.

Here is a lower priced alternative to the Jensen transformers:

http://www.bhphotovideo.com/c/product/381596-REG/ART_DTI_DTI_Transformer_Isolator.html

http://www.artproaudio.com/downloads/specsheet/dti.pdf

I've used this device in non-critical voice recording applications, and in that application it has seemed perfectly transparent sonically.

I'm inclined to think that the problem is not due to noise floor sensitivity, because it seems to be inversely related to volume control setting, it is intermittent, and it is not present on the rca output (where the output level is only 6db lower than on the xlr output).

Good luck!
-- Al

Bleoberis and Almarg, I was in fact thinking that the **output** of the CD player is where this pin 3 to pin 1 thing might have to happen. I understand Almarg's concerns but I have yet to see any line level electronics that could be damaged by this (we do this to our stuff all the time).

Something else you might look into is lifting the ground of the CDP's power cord. It might be as simple as a ground loop.

UPDATE

After all the discussion, had a custom cable made with pin 3 unconnected.

Works like magic.

Thanks for all the help ppls.

Outstanding! I'll let you know when I can come down for the Sam Adams.

-- Al :)