CHAMP ELECTRONICS -" THE VINTAGE VALVE AMP HOSPITAL"

NOTTINGHAM, ENGLAND

 

THE KYRI/CHAMP COMBO AMPLIFIER

(2007)






No it's not a Fender….just an old tweed case being made use of!







Sometime during summer 2007, a really nice gentleman named Kyri contacted me regarding this little home-made amp that he owned. He explained that it wasn't very loud and wondered if I could sort it for him? He also said how much he'd enjoyed the web-site, and that he would love to have my name on his little amp…..Really sweet! I offered to take on the job, and the photo above is how the amp looked on arrival. The tube line-up was: 1 x EZ41 rectifier, 1 x EL85, and 1 x ECC83. The bulb you can see between the rectifier and output transformer is not a "pilot lamp" but in-fact is used as a "load-taking fuse" between the power transformer's HT centre-tap and ground…..I have seen this done before on older equipment!






Front view. Kyri had also asked me if it was possible to have the front brass plate on "fly-leads" for convenience in cabinet mounting plus, could I also change the combination on/off/volume for independent units….as-in a separate on/off toggle switch & volume control………of course, no problem!






The underside as received. Dig the scruffy little choke……it was still working though!






OK, as in any project like this, I'd recommended to Kyri that I simply strip the amp completely and "start-a-fresh"….my way! I also suggested that we go for an EZ81 rectifier & EL84 output tube…..both being much more readily available, plus the original EL85 output tube is only really good for a couple of watts.







As above. One small point here though. I had mentioned to Kyri that the original output transformer, for the EL85 tube, might not be a suitable plate load for an EL84, and that I might need to change this too. I said that I would try things out first to see how it performed.






The brass front plate, now drilled for the input jack, volume, and tone controls, plus a separate power on/off switch and neon.






The underneath fully finished. Now…..doesn't that look so much better!






All completely finished and working/looking really cool! And unfortunately I did have to change the output transformer. (You can just see the replacement peeping through between the power transformer and EL84, with the old one in the junk tray at the back).






When Kyri first got the amp back, he fitted it in this spare tweed Fender case he had, along with an Altai driver. The amp chassis is mounted to the side of the cabinet.






And finally he had a change of plan.......and speaker! I believe he didn't like the sound of the Altai driver so he replaced it for this one. (I'm not sure what brand it is), He also eventually mounted the chassis to the bottom of the cabinet instead of on the side as in the previous photo. At first Kyri said how much he liked the old-fashioned knobs I had chosen for it, but I believe he later changed those for the "chicken-head" style.

Whilst there is nothing special about this amp/circuit, and certainly no "Rocket-Science" in it…..it actually sounds pretty cool. I will add the schematic to the article ASAP, as this is a good little amp to build…….and very easy/simple too!

Thanks for looking.

Cheers, John.






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