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Hoffman Amps Forum image Author Topic: AC15 CC1 mods  (Read 5137 times)

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Offline phsyconoodler

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AC15 CC1 mods
« on: February 22, 2011, 06:52:06 pm »
Is anyone familiar with mods to improve the overdriven sound of the AC15 CC1 combo amp?

  I don't really want to jump in and start changing stuff without a possible plan.It sounds a bit ratty when driven hard.Not like an 18 watt Marshall at all.
  There are a bunch of Youtube clips but no real guide to what mods were actually done.Or at least no schematic guide anyway.

Anyone who has any info on where to get a hold of some of these possible mods?

cheers!
Honey badger don't give a ****

Offline VMS

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Re: AC15 CC1 mods
« Reply #1 on: February 23, 2011, 11:56:26 am »
Here is a couple pages of mods:

http://meyer-repair.blogspot.com/2011/01/vox-ac15-custom-classic-upgrad.html

http://www.guitarpug.com/2008/06/vox-ac15cc-mod-guide/

If you have different speakers, try those with the amp.

Other thing that is mentioned on those mod pages is the removal of the bright cap.

Offline phsyconoodler

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Re: AC15 CC1 mods
« Reply #2 on: February 23, 2011, 05:55:51 pm »
Yeah those mods have been around and they do indeed help,but it's the 'soldano mod' that interests me and info on it is rather vague.

Thanks for the input!
Honey badger don't give a ****

Offline jojokeo

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Re: AC15 CC1 mods
« Reply #3 on: February 24, 2011, 12:55:46 am »
p, did you see the schematic in one of those links? They used 100k load resistors w/ 1k5 w/ 22uFs on both V1 stages' cathodes (these could be tweaked especially the cap values). It appears that the output of V1a only goes through a 470pF cap (seems a bit small) to the TB Vol (w/ that bright cap) and the B+ filter cap has a .01uf smoothing cap accross it (seems a bit much or simply remove it?).
After going through the tone stack they are still reducing the signal by half (seems like a lot) before going into the pi section. That's going to reduce a lot drive going into there. Also check out C15/4n7 & R23/220k going accross the outputs of the pi - (what is that - a type of conjuctive filter?) before going into the power tubes. Lastly w/ a 120r Rk on the el84s, they're running those tubes pretty hot.
To steal ideas from one person is plagiarism. To steal from many is research.

Offline jojokeo

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Re: AC15 CC1 mods
« Reply #4 on: March 02, 2011, 01:20:18 am »
To steal ideas from one person is plagiarism. To steal from many is research.

 


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