I mod my XTC too!

  • Thread starter Thread starter random_guy
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random_guy

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Just sharing in case someone is interested... my Bogner XTC mods so far:

- Marvel-mod on front plate
- MIDI switching of channels (incl. plexi and boost) and cab switch mod
- Cab switch mod
- pilot light took out of the circuit (getting too hot and drawing 300mA!)
- fans inside amp because this amp gets way too hot
- heat sink on the Class A resistors
- MIDI wireless receiver
- remote master volume
- MIDI wireless sender inside the GSC footswitch

Planned mods:
- separate circuits for two different tube pairs in the power amp section
- two different power tube pairs switchable using MIDI
- 22nF coupling cap after third clean stage (instead of stock 10nF) to get the same response curve as a stock Twin Reverb
- modding the poweramp feedback for a better clean

All this should leave the blue and red channels untouched. But I hope to finally get a good clean tone from this amp which is otherwise so good.
 

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What source are you using to power the fan? Any added noise or interference from it?
 
more pics...

The amp finally runs cool!
 

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the power supply uses a voltage stabilizer and is connected to the 15VAC wires of the PT (before the heater and relais circuit's power supply of the XTC). No noise added so far!
 
holy crap that's insane! :thumbsup: :thumbsup: :rock: it looks to me like the DeLorian in Back to the Future! where did you add in the flux capacitor! :lol: :LOL:

awesome work. sounds like it was a lot of fun and it lets the amp do exactly what you want it to do.

i hacked a much more plain cooling fan into mine; a 6 or 8 cm variable-speed computer case fan, bolted to the inside front of the head shell. powered off of the power leads going to the jewel light. if anybody wants to try that, here's the info i used: http://www.blueglow.de/FenFan.html . my XTC was running hot too, but it turned out i had the power tubes biased way too high. :lol: :LOL:
 
Hahaha!! The DeLorean!! :lol: :LOL: And thx for the welcome!
It was a lot of work and fun to do this mods. I'm happy now, specially because I learnt a lot and now have a cab for cleans and one for dirty which makes both sounds better. But I'm somewhat concerned about myself being a bit out of control in the quest for better sound... I hope all this was for something good...
If I do the other mods in the sommer, I'll post them here again.
 
WOW very cool! Did you mess with the NFB loop yet? I think there's a lot to be done there. Great having you here :rock:
 
Everyone around here has 4 fans in their Ecstasy. Just sayin. ;)
 
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