Dumble Heaven Mod

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fyrcrack
Posts: 1
Joined: Tue Feb 12, 2008 12:38 pm

Dumble Heaven Mod

Post by fyrcrack »

Hi guys I'm new here and thrilled to find your group. I have built a few Fender Tweeds and a JTM-45 combo amp. I recently graduated to AB763 circuits. I am building a Fender Twin Reverb and wanted to try Mr. Dumble's Jazz/Rock and Boost circuit for a Twin. Has anyone tried it? Does it work as posted on the Dumble Heaven web site. I am no expert but it looks like a lot of the info there is educated guesswork. I mean no disrespect and am greatfull for everyones contributions.
Where can I get 22Meg resistors? None of the people I deal with stock them.......

Thanks in advance
Firestorm
Posts: 3033
Joined: Fri Jan 25, 2008 7:34 pm
Location: Connecticut

Re: Dumble Heaven Mod

Post by Firestorm »

I can't speak to how it works. But you can get 22M Vishay metal film resistors from Mouser. Part # 594-5073DM22M00J are the 1-watters, Part # 71-CMF55-F-22M are 1/4 watt. Either should be fine in those circuits.
Analog Assassin
Posts: 58
Joined: Mon May 14, 2007 11:15 pm

Re: Dumble Heaven Mod

Post by Analog Assassin »

Just curious, and not to hijack a thread, but what are the differences between the stock blackface clean sound and the dumble clean sound?
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skyboltone
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Location: Sparks, NV, where nowhere looks like home.

Re: Dumble Heaven Mod

Post by skyboltone »

Most leave the Jazz/Rock switch out, leave it in rock, but lifting the ground from the tone stack will give you the boost.
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BluzMike
Posts: 46
Joined: Tue Jul 26, 2005 1:47 pm

Re: Dumble Heaven Mod

Post by BluzMike »

fyrcrack wrote:Hi guys I'm new here and thrilled to find your group. I have built a few Fender Tweeds and a JTM-45 combo amp. I recently graduated to AB763 circuits. I am building a Fender Twin Reverb and wanted to try Mr. Dumble's Jazz/Rock and Boost circuit for a Twin. Has anyone tried it? Does it work as posted on the Dumble Heaven web site. I am no expert but it looks like a lot of the info there is educated guesswork. I mean no disrespect and am greatfull for everyones contributions.
Where can I get 22Meg resistors? None of the people I deal with stock them.......

Thanks in advance
Yes, it does. But I also would not implement a Jazz/Rock switch. Maybe try converting the Normal channel to early 80ies Dumble clean specs with the PAB. Just check the 101 schematic. I have performed this mod with very nice results.
wbfree
Posts: 14
Joined: Wed Mar 05, 2008 3:24 am
Location: Bend, Oregon

rock jazz

Post by wbfree »

BluzMike
What are the results of this mod in the sound of the clean channel. Have been reading as much as I can trying to learn and this sounds like a sensible mod.
I am not a tech, just learning at a very old age :lol:
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