Wampler - Plextortion  [traced]

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indyguitarist
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Post by indyguitarist »

No, the plexidrive is a jfet circuit... 3 gain stages. A little bit similar to the ROG eighteen circuit, but the gain stages are different. The bright switch lifts the ground from the caps on the tail end (dual low pass like the eighteen), Tone control is an additional low pass filter. We are in the process of building a new website that will be along the lines of BYOC except we are doing circuits that they aren't doing yet, including a reverb. I say this because I'll be offering the plextortion, plexidrive and cranked AC pedal kits on there too, and when that's done there will be schematics that I can upload
bw

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Post by erikm5150 »

Is the cranked AC also a 3 gain stage jfet circuit?
I'm lookin forward to that kit and schem when it's available from your site. :applause:

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Post by nooneknows »

Thank you very much! The kit thing is very interesting

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Post by indyguitarist »

erikm5150 wrote:Is the cranked AC also a 3 gain stage jfet circuit?
I'm lookin forward to that kit and schem when it's available from your site. :applause:
yes, but the jfet's are doubled up and the eq between stages is different.

bw

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Post by nooneknows »

I toyed around with my danelectro daddy-o (veeery similiar to the guv'nor, i added the final 22K/470pf filter too), applying the mods posted above, except the jfet stage. The overall sound is better and a bit more marshallesque but the treble are a bit shrill even when they're completely dime out, like the frequency band shifted a bit higher. Do you think it is normal?
I used 10K for R7 and there's a TL072 (it was stock), then I changed all the .22uF electros to .22uF polyester.
thank you

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Post by indyguitarist »

It will be a bit brighter, but the trick is to keep the treble level down in general. Using audio taper pot helps quite a bit (IIRC, stock is linear). If it's too bright, you might consider changing the LP filter so it starts getting rid of highs above 4 or 5k. Running the circuit into a jfet will smooth out the highs a bit too.
bw

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Post by nooneknows »

thank you! I'll try some different cap value.

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Post by nooneknows »

Indyguitarist, you were right a 2.2nF instead of the 470 pF cured the problem. Actually the volume is low, as you already stated, so I'm going to boost the level a bit. Referring to the Guv'nor scheme, did you put the jfet stage where the 22K/470pF are, right?
thank you

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Post by indyguitarist »

nooneknows wrote:Indyguitarist, you were right a 2.2nF instead of the 470 pF cured the problem. Actually the volume is low, as you already stated, so I'm going to boost the level a bit. Referring to the Guv'nor scheme, did you put the jfet stage where the 22K/470pF are, right?
thank you
Actually, I changed that circuit here and there about 10 times! :D
I tried it several different ways... but the way that worked the best is to come out of the eq section - go to a voltage divider 470k/470k to ground. From there, go to the jfet. 15k drain resistor, 1k source resistor. If you want the 'presence' control, connect a pot (50k IIRC) in series with a .22uf cap to ground (from the source pin). Personally, I think it adds too much treble. Volume wise, I think I like just a straight opamp boost out of the eq section... just seems to be less noise and a bit tighter.
As you can see, I change things here and there constantly based on customer feedback.

The newest 'super plextortion' is basically the two opamp stages of this same circuit into a baxandall. Much better bass control circuit. Throw a variable twin t type filter and you can get a mid control as well. That's what I'll be doing on this next version which will have a 3 band eq again.

Hope that helps! :)
bw

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Post by nooneknows »

oh sure, it helps a lot!! thank you very much for the cool infos! I'm going to try it as soon as possible
ciao!

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heavy
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Post by heavy »

hi guys im new in DIY world and this is will be my 1st project :mrgreen: :mrgreen: ... im brian wampler fans LOL plextortion rocks dude!!

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overkill20
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Post by overkill20 »

Hi guys!!
Does anybody have Super plextortion layout and schematics??The pedal sound awsome and would really like to build one myself!

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erigm
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Post by erigm »

indyguitarist wrote:
erikm5150 wrote:Is the cranked AC also a 3 gain stage jfet circuit?
I'm lookin forward to that kit and schem when it's available from your site. :applause:
yes, but the jfet's are doubled up and the eq between stages is different.

bw
Brian, what effect does the parallel jfet's have on the circuit? how does the tone of this arrangement differ from single jfets or mu-amp gain stages?
erigm

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Post by Greg »

I just had a peek inside a Super Plextortion..

Opamp : LM833N
Clippers : 1N4001

No LEDs.
culturejam wrote: We are equal opportunity exposure artists.

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Post by Sweetalk »

Everyone seems to be using the LM833!!

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Post by mrkaploca »

indyguitarist wrote:No, the plexidrive is a jfet circuit... 3 gain stages. A little bit similar to the ROG eighteen circuit, but the gain stages are different. The bright switch lifts the ground from the caps on the tail end (dual low pass like the eighteen), Tone control is an additional low pass filter. We are in the process of building a new website that will be along the lines of BYOC except we are doing circuits that they aren't doing yet, including a reverb. I say this because I'll be offering the plextortion, plexidrive and cranked AC pedal kits on there too, and when that's done there will be schematics that I can upload
bw
any news?
Considering Plextortion,the vintage/modern switch lifts the last capacitor(470p)from ground point of what?

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Post by Old Gregg »

Super Plextortion layout, First version with v2 mods from mmory, had this on my hd.
temp - superplex bright cap.gif

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Post by roseblood11 »

indyguitarist wrote:We are in the process of building a new website that will be along the lines of BYOC except we are doing circuits that they aren't doing yet, including a reverb. I say this because I'll be offering the plextortion, plexidrive and cranked AC pedal kits on there too, and when that's done there will be schematics that I can upload
bw
Great idea, but never realized... :?:

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Post by andregarcia57 »

indyguitarist wrote:No, the plexidrive is a jfet circuit... 3 gain stages. A little bit similar to the ROG eighteen circuit, but the gain stages are different. The bright switch lifts the ground from the caps on the tail end (dual low pass like the eighteen), Tone control is an additional low pass filter. We are in the process of building a new website that will be along the lines of BYOC except we are doing circuits that they aren't doing yet, including a reverb. I say this because I'll be offering the plextortion, plexidrive and cranked AC pedal kits on there too, and when that's done there will be schematics that I can upload
bw

hello how are you Indy?
I've been researching on your pedal and ended up in this thread.
you already sells kits plexidrive.
I want to ride one for me I liked the sound.
I got to ride the eighteen-runnof not got the most sound.
I appreciate the attention.

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indyguitarist
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Post by indyguitarist »

andregarcia57 wrote:
indyguitarist wrote:No, the plexidrive is a jfet circuit... 3 gain stages. A little bit similar to the ROG eighteen circuit, but the gain stages are different. The bright switch lifts the ground from the caps on the tail end (dual low pass like the eighteen), Tone control is an additional low pass filter. We are in the process of building a new website that will be along the lines of BYOC except we are doing circuits that they aren't doing yet, including a reverb. I say this because I'll be offering the plextortion, plexidrive and cranked AC pedal kits on there too, and when that's done there will be schematics that I can upload
bw

hello how are you Indy?
I've been researching on your pedal and ended up in this thread.
you already sells kits plexidrive.
I want to ride one for me I liked the sound.
I got to ride the eighteen-runnof not got the most sound.
I appreciate the attention.

actually, I don't sell any kits at all anymore. We tried it at one time, it things just didn't work out.

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