ac30 w/reverb?

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rriddy
Junior tube assistant
Posts: 41
(2/2/04 8:58 am)
 ac30 w/reverb?
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 Has anyone had success incorporating Doug's reverb mod into the ac30 layout?
 
Rotting27
Junior tube assistant
Posts: 104
(2/2/04 8:10 pm)
 Re:
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 HTML Comments are not allowed
 
GroundhogKen
Forum Moderator
Posts: 2238
(2/3/04 8:39 am)
 Re: Re:
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 Try again Rotting. I don't know why EZboard does that some times.

You might type your message in notepad and then paste into the reply window. That way your text will still be saved and you can try again.

Also put a check in the preview box to see if your reply is going to work.

Ken
 
Rotting27
Junior tube assistant
Posts: 106
(2/3/04 7:44 pm)
 Re: Re:
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 I can't speak on Doug's reverb mod, but I have built 4 AC30s for friends/"customers" that I incorporated reverb in. It's actually not that complicated and sounds great.

In Doug's layout, you'll notice that the tremelo from the stock AC30 is conspicuously absent, so, replace that circuit with a standard fenderesque reverb feeding from the EQ and injecting into the splitter (into the .047uf that is no longer grounded (pin 7 on Doug's layout).

If you can't get it just right, I'll could draw something up for you, but if you just look at a normal fender reverb circuit and think "where is signal input? and where is signal output?" , then make the signal input feed from the EQ (wiper of treble pot), and signal output inject into the .047--to pin7 of the splitter. Then you've got it made!

Edited by: Rotting27 at: 2/3/04 7:48 pm
 
Rotting27
Junior tube assistant
Posts: 106
(2/3/04 7:50 pm)
 Re: Re:
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 Yeah, Ken, I had to try several different times for it to take it. I have no idea what was up with the board.
 
eddiejg
Senior tube assistant
Posts: 213
(2/3/04 11:59 pm)
 ac30 w/reverb?
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 Rotting-
So, you don't need to add a preamp stage in front of the PI like Fender had on their amps?
I guess no 3.3M resistor with a 10pF cap either right?
Just a 500pF cap into the reverb & 470K resistor out of the reverb all coming together at the .047 cap in front of the PI?
-Ed
 
Rotting27
Junior tube assistant
Posts: 107
(2/4/04 3:22 am)
 Re: ac30 w/reverb?
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 No, you don't want to do that. Adding that stage will alter the tone of the amp. We don't want to alter the real AC30 tone.

The method I described is just adding a loop that adds wet signal into the PI. It's a parallel circuit that can be mixed with the dry. Which means we can go from pure dry (natural AC30 tone) to an full parallel mix.

So, no 3.3M or 10pf, and yes to the other questions.

Edited by: Rotting27 at: 2/4/04 3:29 am
 
GroundhogKen
Forum Moderator
Posts: 2239
(2/4/04 7:49 am)
 Re: ac30 w/reverb?
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 Here's what the Vox people tried in the 90s:

www1.korksoft.com/~schem/...30vrev.pdf


Ken
 
rriddy
Junior tube assistant
Posts: 41
(2/4/04 8:25 pm)
 ac30 w/reverb
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 i would appreciate a drawing if you have one done, if ot i'll try and do one myself.
 
Rotting27
Junior tube assistant
Posts: 108
(2/6/04 2:40 am)
 Re: ac30 w/reverb
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 I could draw something up for you. I don't have one, but I could just cut n' paste out of a schematic and make a few notations.

I'll get back to you on this, soon.

 
Rotting27
Junior tube assistant
Posts: 108
(2/8/04 2:48 am)
 Re: ac30 w/reverb?
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 Here you are:

www.geocities.com/rgagiff...everb.html

if you have anymore questions, just ask.

Edited by: Rotting27 at: 2/8/04 3:42 am
 
rriddy
Junior tube assistant
Posts: 41
(2/8/04 10:34 am)
 ac30 w/reverb
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 thanks alot, i'm going to start working on it now.
 
 
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