I need help with build my F3

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Hello,

first sorry for my bad English.

When I adjust the Aleph CCS to 50% ,ca.3,3KOhm for R18 + P2 in Original, and greater the F3 swing. I think I did some wrong in my Layout. Can anybody help me?

I made my own PCB for the F3 because I want learn.

Thanks

The PCB:
 

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I tried a Capacitor between the B and C of the NPN-transistor in the CCS.
With out this C it oscillates at about 200 kHz and with 1nF at 25 kHz (Aleph CCS at 50%).
With 4,7nF the F3 is completely stabile no meter where the P2 stay.
But the bandwidth gets down.
I think I make a new Layout like Peter Daniel.

Can I change the values of the Feedback Resistors 9k to 6,19k and 47k to 31,6k to increase a little bit the bandwidth with out Problems? I think my pre amp will do this (200Ohm output impedance).

With the Aleph CCS at about 10% (no oscillation) it sounds very good. I hope I can hear the F3 with 50% Aleph as soon as possible. :cloud9:
 
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