On Aug 4, 2017, at 6:57 PM, Chris Mehalso wrote: Hi Mister Patch Bay – I am having trouble. Possibly more than one problem. I have 8 outputs on my sound card, so I created 8 outputs on my TT patch bay. One of those stereo pairs is normalled to a pair directly below it that goes to a little headphone amp. The headphone amp accepts TRS input, so I had to build a cable that takes the two balanced channels and combines them onto one TRS that I could plug into the headphone amp. Problem #1 is that I simply cannot get the normals to make sound. I assume this is a problem with the patch modules or my cables from the sound card. I will address this myself. But I tested it by simply using patch cables to grab sound from a known working output. More problems then . . . I am getting a loud hum. I also noticed that the click track sounds clear and appears on BOTH EARS when I only have one of the two patch cables connected. Then I connect the second cable the sound volume drops significantly and the quality is really poor. This seems like a phase error because I built the cable wrong. Here’s how I built it: The TRS end: T – both red conductors from two cables R - both black conductors from two cables S - both ground conductors from two cables The patch bay end: Left cable Black conductor – T Red conductor – not connected Ground conductor – S Right cable Red Conductor – T Black conductor – not connected Ground conductor – S I thought by doing this I would be creating a stereo unbalanced feed from two mono balanced feeds . . . but I appear to be doing something wrong. Can you help?? THANKS Chris Mehalso, CTS COHERENT MEDIA SYSTEMS SPECIALISTBTX TECHNOLOGIES, INC. // www.btx.com//chrism@btx.com// Direct Line: 904.885.0054
Hey Chris,
The input to your TRS headphone amp should be as follows: Left channel hot goes to the tip of your 1/4” TRS cable that plugs into your headphone amp. The Right channel hot goes to the ring of your 1/4” TRS cable that plugs into your headphone amp. The ground on the 1/4” TRS cable that plugs into your headphone amp can come from either left or right channel ground. That’s it. It is two mono channels that drive the stereo headphones.