The BetaBax (or me being too lazy to breadboard a Sunn Beta)

[lrgaraujo]

For some years now, I've enjoyed the sound of the Sunn Beta amps, but the EQ section was always a nightmare for me to create an etchable layout (I like etching my own boards), so now I've finally decided to breadboard a stripped down version to see if it sounds any good.
Since I'm already butchering the circuit, I've decided to see what else I could simplify while retaining a good sounding preamp. First thing I did was converting it to 9Vdc, quite simple, really.
I also found out that I could ditch (for my needs, at least) the dual gain pot, and use a single one (I just leave the second half of the pot fully maxed out all the time).
For the EQ section, I've decided to go with a baxandall, taken from the Xotic RC Booster, but it's not yet working in my breadboard (which is not surprising, considering how bad it looks ), so I might change the frequencies when I listen to it.
So far, I really like how the distortion sounds, and I'm hoping to get the EQ working soon

 

[Sturdag Lagernathy]

So why are the inverters used here and not, say, an op amp? I'm not familiar with the original circuit at all..

 

[lrgaraujo]

So why are the inverters used here and not, say, an op amp? I'm not familiar with the original circuit at all..

That's just how the amp was designed, the inverters are used to generate distortion (similar to a red llama, for example).

 

[lrgaraujo]

Update: eq is now working, this is getting built