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Hoffman Amps Forum image Author Topic: Modded VJ "dark" sound - problem  (Read 1842 times)

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Offline Gareth81

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Modded VJ "dark" sound - problem
« on: January 05, 2013, 03:54:19 am »
Hi All

I have a Epiphone VJ, I used a drop in replacement turret board from WATTS Tube audio

 I am using the "fenderish" board.

Something is not right, the amp powers up and works but ist has no highs at all.. The output transformer is a champ transformer although I am running an el34, could this be the cause? I was using this trannsformer before I replaced the board without any issues....

Any suggestions would be appreciated.

Regards
Gareth

« Last Edit: January 05, 2013, 03:59:02 am by Gareth81 »

Offline Geezer

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Re: Modded VJ "dark" sound - problem
« Reply #1 on: January 05, 2013, 07:09:16 am »
First, go over the layout, comparing with your actual amp, highlighting as you go to make sure everything matches up, is correct.

Go over every joint, wire and connection with magnifiers on, looking for a stray wire or bad solder joint.

So, the amp worked fine with the EL34 and champ OT before the board transplant, correct?

Measure all the voltages and post them.....someone may spot a wayward voltage that reveals a problem area....

Good luck, G
   Cunfuze-us say: "He who say "It can't be done" should stay out of way of him who doing it!"

Offline sluckey

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Re: Modded VJ "dark" sound - problem
« Reply #2 on: January 05, 2013, 08:46:24 am »
The Fenderish/octal board is meant for 6V6. To use an EL34 you need a jumper between pins 8 and 1 of the octal socket. This may not be your problem. Here's the diagram for the Fenderish/octal board...
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

 


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