JLH Headphone Amp

How do I wire the headphone jack ?

There is Right + / - and Left + / -, the jack has Tip, GR and GI. Thank you !
 

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It Works !

Make sure you don't connect the green and blue from the same secondary!
(Asegúrese de no conectar el verde y el azul de la misma secundaria!)

You have interchanged the inputs (RCA) and the output (6,3mm jack).


Thank You ! Thank you !

It works. Now working to get rid of grounding hum and have stereo separation.
 

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Thank you sgrossklass,
Yes, I am getting a grounding hum. Can you make a suggestion for grounding scheme ?

Refer back to the image in post 656.
Instead of using the output grounds near the outside of the board like you're doing, try connecting both grounds to the long, wide ground trace in the center of the board.

Scrape off some of the soldermask on that trace and solder both output grounds to that point.
I always connect the grounds near the bottom of the trace close to where the 4 smaller traces exit.


That helped the hum I had, but you may have something other grounding issue(s).
 
I wonder how it works - your pics show input RCA plugs and output headphone plug with no GND wire connected.

...Well it sort of works. Have sound from both headphones, but no separation left / right. Suggestions ? Using Neutrik 1/4" Thank you !
 

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Hum + No Stereo JHL

A big thank you to ammel68 for his patience and guidance!

I took a couple of weeks off working on the JHL, was getting frustrated.

Still having trouble:
1. Have a loud grounding hum, gets louder if I touch any metal parts of the JHL, headphone jack, dac, etc.
2. No stereo separation, both channels playing the same audio.

Suggestions ?

Thank you !
 

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Are the two RCAs separate input channels?
The input to the amplifier should be a two wire connection and for loew emi these TWO wires must be close coupled. You can use coaxial or twisted pair.
For a stereo input you NEED two pairs of wires. One pair for each input.

What are the two red wires?
What are the four bue and green wires?
 
For a stereo input you NEED two pairs of wires. One pair for each input.

What are the two red wires?
What are the four bue and green wires?

No you don't. I've used a common ground between both inputs before without any issues. Three twisted wires work just fine.
In addition, the board only has a provision for 3 wires on the inputs.

The red wires on each side are the L+ and R+ outputs.

The blue and green wires are from his Antek power transformer.
 
Still having trouble:
1. Have a loud grounding hum, gets louder
No you don't. I've used a common ground between both inputs before without any issues. Three twisted wires work just fine.
In addition, the board only has a provision for 3 wires on the inputs.

The red wires on each side are the L+ and R+ outputs.

The blue and green wires are from his Antek power transformer.
your solution does not work for him.