BF Champ Reverb (SE Princeton Reverb) Style Amp Build Report

molomo74

TDPRI Member
Joined
Aug 12, 2021
Posts
15
Age
27
Location
Germany
Hello dear fellow ampliophiles ;)

I am in the planning stage for an upcoming Blackface Champ Reverb Style build and i would document the process and share some photos if anyone is interested.

So far i have the schematic und layout ready and basically all the parts i need (a few parts are still missing).

As for the schematic i meshed up the fender princeton reverb and the blackface champ schematics. So i took the princeton reverb, ditched the tremolo (because i want to put it into a bf champ/vibro champ style chassis) and added the SE output stage of the champ.
I will post the schematic and would be very pleased if anyone could go over it and keep an eye open for possible mistakes. The voltages are not true to the voltages i will possibly get (since i meshed the two schematics together and they have quite different voltages in general).

For the PS Filtering i decided to take the Champ style Filtering (so 3 Filter Caps) istead of the princeton but with an enlarged first Filter Cap (33uF, because i had one on hand and i recently built a vibro champ which needed some extra filtering from the stock 20-20-20). What do you think about this?

I possibly have to play around with the dropping resistors once i got the amp together and be able measure the voltages. But my concern is i don't really know what to go for on the plates of the 12AX7s. Should i go for 160V on all 4 12AX7 plates like on the princeton reverb?
Or go for 200V on the plates of V1 like in the vibro champ schematics? Or maybe it doesn't matter that much?

I also attached the first version of the layout plan. Feel free to comment or criticize :)

Greetings,
Mo
 

Attachments

  • SCHEMATIC CHAMP REVERB.pdf
    601.9 KB · Views: 50
  • Layout.pdf
    293.7 KB · Views: 32

cometazzi

Friend of Leo's
Silver Supporter
Joined
Dec 3, 2019
Posts
2,053
Location
Wisconsin, Das Land von Käse und Bier
Also interested. Some time ago I drew up something similar, but I basically added Reverb (also with a Dwell control) to a VibroChamp. I wanted both the reverb AND the trem in a 5W amp.

This looks a lot more concise, however.

Edit: Just realized this is in the Amp Tech Center. This thread would possibly have a better run in the DIY/Shock Brother's forum.
 
Last edited:




Top