Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Colas LeGrippa on March 24, 2015, 02:41:01 pm

Title: Push pull 50W, suggestions ?
Post by: Colas LeGrippa on March 24, 2015, 02:41:01 pm

Hi, I am looking for a next project to build. I want to build a 50W PP guitar amplifier that rocks, SS rectified.

thanks for ideas !

Colas LeGrippa

Title: Re: Push pull 50W, suggestions ?
Post by: Colas LeGrippa on March 24, 2015, 02:42:55 pm

.....an amp that rocks but not with lots of distortion . My favorite tubes are 6550's and EL34's .

Title: Re: Push pull 50W, suggestions ?
Post by: sluckey on March 24, 2015, 02:45:10 pm

I think Marshall did one, if you don't mind an import.

Sunn did several amps using those tubes.

Title: Re: Push pull 50W, suggestions ?
Post by: shooter on March 24, 2015, 05:04:20 pm

I stole Sluckeys stuffed Vox for a similar build, although I'm using EL34s cathode biased.  with fixed bias and the right B+ I would think you'd get close to 50W  I attached the preamp section FWIW, I'm still dialing the values but she's way to loud for my shop!  I like the blend feature, the sound is "wooly" clean, warm vs crisp and sharp, that's before the EL's get angry, after that she's just plain mean!

Title: Re: Push pull 50W, suggestions ?
Post by: glassesnvests on March 24, 2015, 07:24:27 pm

Ceriatone has a layout for their "Hot Rodded Plexi" Chupacabra. It's a pretty fantastic amp, very versatile and handy. Has an "era" switch that changed diode clipping to make it sound like 3 different decades of the plexi.

Title: Re: Push pull 50W, suggestions ?
Post by: Glennjeff on March 24, 2015, 08:31:11 pm

I believe "The Yeti" is similar to "Chupacabra" but more capable of clean tones. It may be a better choice for Colas LeGrippa.

Schematics can be pulled from overlays. :wink:

Hoffmans layouts and grounding schemes are the most logical out there IMHO.

Title: Re: Push pull 50W, suggestions ?
Post by: Colas LeGrippa on March 24, 2015, 08:54:59 pm

If you'd have the schems of the Chupacabra, it would sure make my day !

Colas

Title: Re: Push pull 50W, suggestions ?
Post by: Glennjeff on March 24, 2015, 09:23:48 pm

Here are the requested  Preamps, PI, PA and PS


There may be errors although it has been triple checked.
Voltage doublers do my head in for some bizarre reason so check the DC heater supply very carefully.