B-15 Preamp

[ogrepraxy]

Hello everyone. I am currently trying to learn to read schematics, and how the various parts of an amp work together.

I’m wanting to build myself an Ampeg B-15, but just the preamp, and add a direct out with transformer.

Can anyone help with this mod?

Thank you.

 

[soapfoot]

There were a few revisions of the B-15

Most (all?) have a direct out labeled “EXT AMP OUT”

I’m not sure the source impedance of that output offhand (it follows a 6SL7) but theoretically it seems like you could just delete the power amp section and the second preamp section

If you wanted it balanced, you could choose an appropriate transformer

 

[rock soderstrom]

@mods please merge the two identical B15 threads and delete my post.