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Hoffman Amps Forum image Author Topic: 18 Watt PI cap question...  (Read 4784 times)

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Offline TubeGeek

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18 Watt PI cap question...
« on: April 06, 2010, 08:53:21 pm »
It was a while back I read on this forum that there was a difference between the original 18 watt and Doug's Stout in that the 0.022µF cap should go directly from v2 grid to ground instead of through the 47k resistor to ground.

I did this mod last night and it opened up the normal channel A LOT and turned the hotswitch into a thick distortion switch.

I just want to make sure I did the correct mod.  Did I?

Offline sluckey

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Re: 18 Watt PI cap question...
« Reply #1 on: April 06, 2010, 10:10:18 pm »
Yes. Your posted layout has the cap connected the same as the original Marshall amp was connected.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline TubeGeek

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Re: 18 Watt PI cap question...
« Reply #2 on: April 06, 2010, 10:44:05 pm »
Thanks.  I thought I'd check just to be sure.

This mod makes a huge difference and I like it. :headbang:

 


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