Ceriatone Chupacabra's "Pussy Trim" control on JMP50?

[lgehrig4]

This looks interesting. Supposedly fine tunes the gain and saturation, but I'm not sure if this would work on a stock 50W plexi build. In looking at these 2 layouts the only part I'm questioning is V1 pin 7. On the plexi it goes to the 68K resistors to the inputs, but on the Chupacrabra this goes to what would be the center lug on the normal volume pot.

Can anyone take a look at this and tell if it would work on the 50W plexi?

Plexi
http://www.ceriatone.com/ceriatone/wp-c ... 0-Lead.jpg

Chupacabra
http://www.ceriatone.com/ceriatone/wp-c ... t-2015.jpg

[bmx]

I suppose you could do it. It would work as it does in the Chupa if you set your "Normal" gain to minimum . The "Pussy Trim" in the Chupacabra is a 1M pot to ground in place of the 470k Mixing resistor.

[lgehrig4]

I suppose you could do it. It would work as it does in the Chupa if you set your "Normal" gain to minimum . The "Pussy Trim" in the Chupacabra is a 1M pot to ground in place of the 470k Mixing resistor.

What about those 68k resistors in the Plexi? Also connect to pin 7?

[Roe]

not a great idea. just adjust the unused volume of the jmp50 instead, since it affects the voltage divider used on both channels

[lgehrig4]

not a great idea. just adjust the unused volume of the jmp50 instead, since it affects the voltage divider used on both channels

I'm sorry, but could you provide a little more detail. I don't understand what you mean but I'm curious.

[bmx]

I suppose you could do it. It would work as it does in the Chupa if you set your "Normal" gain to minimum . The "Pussy Trim" in the Chupacabra is a 1M pot to ground in place of the 470k Mixing resistor.

What about those 68k resistors in the Plexi? Also connect to pin 7?

68k resistors are on the inputs of the first stage. We are talking about the input to the second stage.

There are several differences between the Chupa and the Plexi. For the Chupa "Pussy Trim" is on the input to the Third stage. So, it will have more chance to effect saturation etc. The Plexiglas has two stages and placing the pussy trim before the second stage may not totally have the same effect. Though it might! I can get very good tones with just a Plexiglas stage and if you are boosting it with a tube screamer or treble booster or what have you, it will likely be useful to getting just a touch more.

My thought was that you would put a 1M "Pussy trim" pot in place of the 470k Mix resistor that connects to the Normal Volume pot. Personally, even when jumping a Plexiglas circuit, I really mix the normal channel very high. So having a 1M mix resistor would result in the "Pussy Trim" circuit when the Normal volume is at Zero. When you are using the Normal volume, this new Pussy Trim will be an adjustable mix resistor. My guess is there will be some sounds there to play with!

It depends on how you use your Plexiglas. If you do like me and have the normal volume off usually, go for it.

[lgehrig4]

I suppose you could do it. It would work as it does in the Chupa if you set your "Normal" gain to minimum . The "Pussy Trim" in the Chupacabra is a 1M pot to ground in place of the 470k Mixing resistor.

What about those 68k resistors in the Plexi? Also connect to pin 7?

68k resistors are on the inputs of the first stage. We are talking about the input to the second stage.

There are several differences between the Chupa and the Plexi. For the Chupa "Pussy Trim" is on the input to the Third stage. So, it will have more chance to effect saturation etc. The Plexiglas has two stages and placing the pussy trim before the second stage may not totally have the same effect. Though it might! I can get very good tones with just a Plexiglas stage and if you are boosting it with a tube screamer or treble booster or what have you, it will likely be useful to getting just a touch more.

My thought was that you would put a 1M "Pussy trim" pot in place of the 470k Mix resistor that connects to the Normal Volume pot. Personally, even when jumping a Plexiglas circuit, I really mix the normal channel very high. So having a 1M mix resistor would result in the "Pussy Trim" circuit when the Normal volume is at Zero. When you are using the Normal volume, this new Pussy Trim will be an adjustable mix resistor. My guess is there will be some sounds there to play with!

It depends on how you use your Plexiglas. If you do like me and have the normal volume off usually, go for it.

Thank you, that sounds interesting. I'm going to take a moment to digest what you wrote and study the circuit a little more for better understanding.