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Hoffman Amps Forum image Author Topic: MPF 102 question  (Read 6880 times)

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Offline tubenit

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MPF 102 question
« on: July 03, 2023, 06:29:31 am »
As I understand this circuit ........... it appears to be similar to a reasonably standard Crybaby pedal circuit with an MPF102 in front and behind the Crybaby circuit.


What exactly is the MPF102 adding to the Crybaby tone?  Is this a gain, a distortion or a fuzz addition???


I am wondering if this could be cluttering or muffling the vowel/wah tone some?  I built this pedal yrs ago and have never bonded well with this circuit.  I'm considering removing the MPF102 circuitry after the original Crybaby circuitry to see if it improves the tone.


I'd like sort of a cleanish smooth wah vowel tone.


Thanks, Jeff

Offline sluckey

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Re: MPF 102 question
« Reply #1 on: July 03, 2023, 07:18:35 am »
The MPF102 is a JFET. Both are being used as a source follower. No gain. I don't know how they may affect the sound.

Here's the original Crybaby from the late '60s...
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline tubenit

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Re: MPF 102 question
« Reply #2 on: July 03, 2023, 02:31:51 pm »
Steve,  thank you!  I appreciate the info and the schematic! 


Best regards,  Jeff

 


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