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.