DIY Mic Pre Kits, Lunchbox Mic Preamp Kits, Power Supply Kits

Mr. Owel... how many licks does it take to get to the tootsie roll center of a tootsie pop???

Just kidding ha!

I finally got around to testing out some of these preamps from you. For the most part they sound as amazing as expected But I'm having a bit o trouble. Most importantly, at high gains (past about 3 oclock position) i lose all signal and all i hear is white noise. Also (not sure if it's related or not but...), it sounds like there's some popping when i change gains. Gets louder with gain. Sounds like DC offset somewhere maybe?

Also, its kinda strange that i have two identical units (assembled at the same time with the same parts, etc.) and both exhibit the exact same behavior.

Have ya had this before? Any tips where to start troubleshooting?

Thank you, sir!

GG, that's a new one for me. Never heard of that kind of problem before. You shouldn't lose signal even at high gains. There may be clicking sound at high gains and louder clicks at higher gains, but not bone-jarring popping sound.

Did you buy these as a KITs or pre-assembled?

I know you bought some PCBs from me (partial kits) but not the full kits, right?

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Yeah i just bought partial kits. Some PCBs and switches and stuff. I sourced most of the parts.

No worries, i just thought maybe if you heard of it before.

I'll look into it some more and keep ya posted!

Thanks!

Can you take a photo of the top view and bottom view of the board? Email it to me.
Thanks.

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Update:

Thanks to the help of Owel, a few unnecessary parts were the cause of the problem. I had installed a few parts that i did not need, since i was not using the input transformer.

I removed the pair of 2M2 resistors and 33pf near IC1 and it solved the problem! Sounds great now!

Thanks again.