Fender Champion 600

[tot_Ou_tard]

Since the Valve Jr has such a presence on the Fret & it looks like the BlackHeart amps are the up & comers. I'd thought I'd make sure that the 600 doesn't get lost in the crowd (it's teeny-tiny).

tung, mentioned in the VJ mod thread that he suggest changing the output transformer. What changes in tone could I expect if that was done?

Yes, the main problem is getting thunderous bass with the 6in speaker, but it does great for basement jamming. Someday I might get a 1x12 cab.

 

[just strum]

I wasn't familiar with the 600, here is a little youtube demo




Not a bad little amp.

 

[tot_Ou_tard]

I'm thinking about modding this beaut with new transformers.

Tung said this on another thread:

Since the Champion 600 is tweaked version of the 5F1 Champ, you could use Hammond's 125CSE, 125DSE, or 125ESE. Any of those would work, but you'd get the best bass response with the 125ESE.

I've used the 125ESE in about 5 or so Tweed Champ/Princeton circuits and it works well. Vintage Champs/Princetons had an OT with about 7.6k for the primary. I'm not sure what the primary is on the Champion 600 though. When using the Hammonds, the closest you can get is 5K, but in my experience it sounds great. The 125ESE is huge though, it might be hard to shoehorn into the chassis.

Edit: the best place to buy Hammond iron right now is www.radiodaze.com

Heck, by all acounts the Champion 600 OT sounds pretty good, you may not even need to change it.

Looking on the radiodaze site I see a Hammond 1750C spec'd at 7k for Fender Champs marked as similar to 125A35A & 022905, but no mention of the 125ESE. Is this a good option?

Any other suggestions, opinions?

Also, does anyone change the power transformer? I always hear talk about the OT.

 

[Ch0jin]

I'm trying to think of reasons to change a power transformer.

As the power source for your amp I can only think that a different PT would give either the capacity for higher current delivery (if the B+ to your power stage is sagging under load) Maybe not ideal in a small tube amp. After all, the most prized champs had a tube rectifier and supposedly these do sag noticably at full volume adding to the unique tone of an amp of this nature.

If your power stage B+ is rock solid then increasing the current rating of your PT should have no effect.

The other thing a different PT could supply is higher B+. I suppose if the power tubes arent running close to their maximum B+ you could bump it up for a louder amp, but I suspect a mod like this would require substantial component changes.

The only practical reason I can think of (as I sip my coffee and ponder going back to work) would be if you need to power some other mods in the amp. Say you wanted to build in a reverb tank/tremelo or something. You could get a PT with a third secondary winding that gave you 9VAC or similar and u could rectify and filter that and use it to power your onboard FX.


Anyway, in summary, No, I can't think why you'd bother replacing the PT

 

[M29]

Hello,

I hardly ever hear of a power transformer swap. Not much reason I suppose unless you are making big changes in components.

I don't know what the difference is but I changed the output transformer in my Valve Junior (Hammond 125DSE) and up graded my GDS 18 watt with a GDS upgraded (Vintage) transformer and they both made a world of difference. A much sweeter more defined and articulate sound. Well worth the extra dough and the work putting them in. I highly suggest an output transformer swap.

IMHO of course

M29

 

[tot_Ou_tard]

So there is a reason that one doesn't hear about PT swaps. T

hanks Ch0jin & M29!

Is the Hammond OT that I mentioned a good choice for this amph?