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Hoffman Amps Forum image Author Topic: Master volume mod - AC30  (Read 5539 times)

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Offline Dan The Man

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Master volume mod - AC30
« on: May 22, 2016, 11:35:10 am »
Please show me how I can add a master volume to my Vox AC30 TB. I have read you could bypass the cap at the cut control, but I'd prefer to keep the cut control as it is. Are there any other ways to install a MV? I have installed a couple of PPIMV's in Marshalls. Can I do a similar installation in an AC30?
I don't follow schematics so well, so if you have layouts or images that I can follow in detail I will be happy.

Thanks.
Dan

Offline sluckey

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Re: Master volume mod - AC30
« Reply #1 on: May 22, 2016, 12:12:01 pm »
Try putting a jumper across your cut control cap. Then play with the pot to see if you like the crossline mv. If you like it, it's very easy to add. Look at this pdf. My brilliance control is the same as your cut control.

     http://sluckeyamps.com/lightning/matchless_lightning.pdf

There are some others that I like better. Search for LarMar master volume.
« Last Edit: May 22, 2016, 12:34:20 pm by sluckey »
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Dan The Man

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Re: Master volume mod - AC30
« Reply #2 on: May 22, 2016, 02:01:31 pm »
Thanks! But then I don't have the cut control anymore.

Offline sluckey

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Re: Master volume mod - AC30
« Reply #3 on: May 22, 2016, 02:08:58 pm »
This is just temporary to see if you like it without having to actually add the mv. If you like it then add it and you will have your cut and mv.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline shooter

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Re: Master volume mod - AC30
« Reply #4 on: May 22, 2016, 07:22:36 pm »
Quote
My brilliance control
Can I ask, do you like the brilliance control, I copied/used the clubman's PA section, but it seems to loose something tonally?  Thx, sorry for the hi-jack
Went Class C for efficiency

Offline sluckey

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Re: Master volume mod - AC30
« Reply #5 on: May 22, 2016, 08:17:33 pm »
I never bonded with that Matchless Lightning amp. I thought that crossline MV really sucked. I just couldn't get used to it. The Lightning became a donor for the AC-15. The brilliance control is now called a top cut control and I like it pretty good. In fact, I think it's necessary for the AC-15, which really has no tone controls.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline HotBluePlates

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Re: Master volume mod - AC30
« Reply #6 on: May 22, 2016, 08:52:39 pm »
Can I ask, do you like the brilliance control, I copied/used the clubman's PA section, but it seems to loose something tonally?

I thought, "Yeah, the treble," when I read this.  :l2:

I use the same control in my 25L15-type amp. You may have to tailor the pot and/or cap values to adjust the circuit to your amp. I felt it would be a necessity with a D-130 and its aluminum dust cap. Sometimes I engage it, sometimes not, depending on the guitar and other control settings.

Offline shooter

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Re: Master volume mod - AC30
« Reply #7 on: May 23, 2016, 08:50:52 am »
Quote
I never bonded with that Matchless Lightning amp
I love my *plexi*-clubman, tonally it's my best sound so far, but the brilliance knob seems to *gut* most of the good tone in favor of low volume.  Thanks for the info
 
Went Class C for efficiency

 


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