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Hoffman Amps Forum image Author Topic: Using C 30 transformers to build handwired amp?  (Read 2197 times)

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Offline Speakz

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Using C 30 transformers to build handwired amp?
« on: January 01, 2014, 05:12:14 pm »
Wondering if anyone has gutted a Peavey classic 30 and built another amp with the transformers?  I have one which I've made changes and sounds good overall but am considering using for a new amp after I finish the BFVR I'm building. 

I was thinking of building a bassman style circuit and using the 4xel84 style transformers to power it. Anyone tried something like this? Thanks for your thoughts

Offline Speakz

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Re: Using C 30 transformers to build handwired amp?
« Reply #1 on: January 01, 2014, 07:00:51 pm »
https://taweber.powweb.com/store/6m36tmbc_layout.jpg

Wondering if this schematic would work since its a similar power setup? I would want to add a presence control.  Any observations about this schematic and thoughts on tone  or anything at all would be great I could find anything on it but it looks somewhat simple?

Offline tubeswell

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Re: Using C 30 transformers to build handwired amp?
« Reply #2 on: January 02, 2014, 02:13:43 am »
The heaters in C30 are DC wired in series for the pre-amp, and just plain wired in series for the output stage. As long as you copy that you should be okay
A bus stops at a bus station. A train stops at a train station. On my desk, I have a work station.

Offline smackoj

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Re: Using C 30 transformers to build handwired amp?
« Reply #3 on: January 02, 2014, 07:45:00 am »
why don't you try changing the OT and the speaker(s ) before rebuilding the whole amp? those two parts should make plenty of difference in the tone without gutting and rebuilding. I'm guessing you have already chg'd the tubes? IMO, rebuilding without changing the OT and the spkrs, you aren't gonna get that much change vs. how much time and money involved to do the remake.  just one ol man's opinion.

jd    :icon_biggrin:

Offline Speakz

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Re: Using C 30 transformers to build handwired amp?
« Reply #4 on: January 02, 2014, 08:27:33 pm »
Thanks guys.  So far I've changed:
tone caps to orange drop for mid and bass value to a .047 with a silver mica for treble
New Reverb Tank
JJ Power Tubes
Tung Sol in V1
Weber c1230 Speaker

It actually sounds very good but I'm having a sound that tales off occasionally at the end of a note which I think is a tube vibrating.  This based on what the blue guitar mods said might occur when changing the bass cap value.  I read that you can put weather stripping between the chassis and the amp to help dampen things and reduce the rattle.  The buzz is much better now than before as well but still present above 3 on the reverb.

This amp has been my test bed to learn on.   

 


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