Quick Champ Transformer Question

[Turbo7MN]

Hey,

I'm planning on building a 5C1 champ head pretty soon and I'm putting together a list of components right now. I'm pretty set on using a Heyboer Champ transformer with 4/8 taps, but I'm curious - anyone else have a preference for any other transformers before I go for the heyboer?

Also, I'm not exactly sure which power transformer I should get. I'm going with a Hammond for sure, but I'm not sure which one would work the best. I'm going to be building this hopefully pretty close to the original specs, which means about 340VDC B+ with a 5Y3 rectifier. Here's Hammonds power transformer list:

http://www.hammondmfg.com/263.htm

I've searched but all I've found is what to use with a SS rectifier, which is something I will not do. Thanks in advance for any suggestions.

-Darren

[stokes]

From that list I would say the 272DX would be good.The 3amp 5v fil tap is good if you want to try different tube rectifiers that may need more than the 2amp winding.

[sportster4eva]

I'm thinking the Hammond 272 would do the trick, as Mr Stokes has said. It has good current capacity, 5v winding, and will put you around 340v B+ using a 5y3, running on 120vac mains.

I edited this reply after I pulled my head out, and remembered my inadequate math skills...

[Turbo7MN]

Yeah, I was leaning towards the 270CAX actually. I'd rather not run it too high, the 270CAX seems like a good match. Thanks for the input, I think I'll go with that one.

[sportster4eva]

Yeah, I was leaning towards the 270CAX actually. I'd rather not run it too high, the 270CAX seems like a good match. Thanks for the input, I think I'll go with that one.

You could just drop a few volts with a resistor or zener in series to get it lower, if you went with the other tranny, and see which way you like the sound. 6v6's sound so good running hot
OTOH, I have a champ-like clone I made that runs 280-290v and it really rips when you crank it up.

[Turbo7MN]

Ahh, so the 272DX is the better choice then? This is my first total scratch build, usually I like to heavily modify PA amps so the power supply design and transformer are already there and I just have to focus on making it sound good . Worst case I guess I can play with resistor values. Thanks for the reccomendation.

-Darren

[stokes]

I just realized which Champ you were talking about.The 5C1 circuit is weaker sounding than the 5E1 or 5F1,just in case you have never heard one,I thought I would point it out to you.

[nico.verduin]

I just realized which Champ you were talking about.The 5C1 circuit is weaker sounding than the 5E1 or 5F1,just in case you have never heard one,I thought I would point it out to you.

I have a combination of both pre-amps in my diy champ. I am assuming you mean that the 5C1 is not as loud as the 5F1 (which is definitely the case). However it has a very nice darker sound which can be tweaked a bit with a small silver mica cap on the potmeter. My PT is an old transformer from a tube radio and I have a very large SE OT (giving it a nice bass).

[stokes]

Nico,by weaker,yes I mean not as loud,not as much gain,very dull sounding.I have had a couple of people come to me over the years with these amps wondering why the amps sound like crap compared to what they were expecting from a Tweed Champ.They paid top dollar for them,as the collectors value is quite high,but for those looking for a good sounding Champ,it is not the way to go.I usually have no problem modding an amp to get better performance from it,as I have no interest in collectors values,but in the case of an original 5C1,to me its only value is as a collectors piece.So my advice to Turbo7 would be to build a 5E1 or 5F1 as it will sound much better.The only times I have seen an original 5C1,the owners were very dissatisfied with what they had.