Convert XLR to TRS Headphone Cable Issue

wncrob

3 wires connecting the XLR to the TRS are properly matched, but I cannot visually confirm unless I remove his shrink wrap.

You can use an inexpensive multimeter to check continuity between the connectors.

My first post in this thread was poorly worded, so I’ve deleted it in favor of this:

wncrob

I had a 3 wire (cable) 8’ extension cable made that is terminated female TRS to connect with the headphone cable and XLR to plug into the amp/out fixture ...  My headphone amp is "fully balanced" ...

If your headphone extension cable has only three wires, it cannot be a balanced stereo cable. That would require at least four wires: a separate positive and negative for each channel.

Seems that you are only getting one channel - mono operation - which is why there is no soundstage.  For balanced operation in stereo (two channels) you need two XLR connections, not one.  It would help if we had the model number of the Musical Fidelity headphone amplifier.  My guess is that it has two XLR output sockets?

richardbrand

For balanced operation in stereo (two channels) you need two XLR connections, not one. 

There are four- and five-pin XLR connectors that allow for balanced stereo operation in a single cable. My Moon 430HA offers a 4-pin jack as a connection option. Here’s a five-pin from Neutrik, which would allow shielding to be added to the four signal conductors:

The headphone amp is model MX-HPA...it was sold as new and heavily discounted.  Remember, I am not well educated on electrical matters...but have learned (I think) a lot in the past few days.  This amp is advertised as "Fully Balanced" with a pair of combo TRS/3-pin XLT output connectors...while the output connector to the headphone allows TRS or 3-pin XLR connectors, not a 4 pin outlet which balanced to balanced-designed headphone would seem to require....and my experience with a 3-pin XLR to TRS adapter cable (proper continuity confirmed) is that the XLR termination does not convey sound staging 9sounds mono), but with the TRS termination using the headphone cable without the adapter, I get full sound staging and musicality.  I'm beginning to think that there is an issue with the AMP. I should get proper sound staging with the 3-pin XLR connector irrespective of whether it was balanced or not...presumably the manufacturer has that figured out and properly wired everything...or not.  Its at the selling dealer today to be analyzed...will be interested to see if they can replicate my experience. So far, they have been excellent to deal with, but I doubt it can be "fixed" for XLR functionality, and a replacement is likely to have the same issues.  But I'm happy with TRS-only connection based upon what I heard before I got the 3-pin XLR to TRS adapter cable.