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Hi all

I built my first toob amp in 1992, a champ on a perspex panel which sounded amazing.
So I decided to move it to a rack case and add an extra valve for a couple of gain stages and do a PCB. Anyway it never worked and got stuck away in the garage.

I pulled it out this week and I would like to finish it but with a new PCB or tag board, and I am not sure what design to use for the preamp.

My thinking goes along these lines:

1. Champ 5F1 with 1 extra gain stage and bass treble EQ.

2. Vibro champ (champ with vibrato)

3. Marshall JCM 800 preamp for a bit of vibe!

What do you esteemed musos and techies think?

Pics of the old girl



    Wow, that's awesome! I have no suggestions as I'm a complete noob with toobs... but, i'll definitely be following!
      I'd go with one of the original Fender style preamps. JCM800 style is going to push it too hard and, let's face it, a tremolo channel on an amp is useless. That's what I would have done either way.
        I would say, it's not that easy designing a preamp. The trouble you have to compromise between includes oscillation, excess gain, sufficient drive voltage, insertion loss, pot sensitivity, tone flexibility etc.
        Rather use an existing preamp design, there's plenty to go around (and even ones without tremolo if you're worried like ez). Even just studying the differences between them will be useful and get your mind going.
          14 days later
          So I came up with a real bastard here. Blackface Bassman front end with added mid control, coupled to the power section of a 5E1 Champ. Soild state rectifier.

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