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O2 Headphone Amplifier GB

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Hmm... It is a bit dodgy. When the next batch of boards arrive I'll be in touch and we can sort something out.
Okay, that's not what I wanted to read. :worried:
So, basically, you're calling this "dodgy" in a "the boards were probably lost somewhere out there" way, right? Well... that's a pity. And bad luck, I guess. 🙄

Nevertheless, thanks so much for your support, Olli!
Should I sing up to the second GB, just to make sure I'm in, or could you just send me a quick note?
 
How to lower the gain?

the stock is 2.5 / 6.5

so i removed the 6.5 gain resistors from r19/r23, then moved the 2.5 gain resistors from r17/r21 to r19/r23

no resistor = 1.0 gain

-joe

It is a minor point, but if you are settled on 1x as one of your gain settings, I'd put a 10k~50k resistor in there instead of leaving it open. A little current shunt to ground will improve noise immunity a touch, likely inaudible in 99% of situations. You certainly wouldn't be able to detect the small increase above unity gain.
 
It is a minor point, but if you are settled on 1x as one of your gain settings, I'd put a 10k~50k resistor in there instead of leaving it open. A little current shunt to ground will improve noise immunity a touch, likely inaudible in 99% of situations. You certainly wouldn't be able to detect the small increase above unity gain.

<looks over at his pile of resistors>

I will try that.. thanks

-joe
 
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