Mad Professor 1

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Mad Professor 1

Postby rmroza » 09 May 2017, 04:12

Man, I was searching and looked up Top pedals to get VH tone (and late 70's/early 80's) and this pedal came up at the top of the list.

I looked at the videos and it sounded amazing. I ordered one to try out andsure enough, it really does mimic the tone in a clean amp!

I took a quick look inside and discovered a myriad of things from the SpinSemiconductor FV-1 reverb chip, NE5534 Op Amps, 2N7000 MOSFETs, and BC550 BJTs!

Does anyone else have any information on this pedal? If so, please post. If not and in any event, I may take this apart and trace it completely to understand the design.

The reverb is nice, but I'd like is seggregated from the distortion. Likewise, I'd like some tone controls added to adjust the TMB. I wonder if say the Mighty Red Distortion pedal is the same distortion, but without reverb or a variation??!?

Stay Tuned!

https://www.mpamp.com/factory-pedals/1-factory-pedal/

https://youtu.be/8L2cF_89HdM
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Re: Mad Professor 1

Postby caspercody » 09 May 2017, 20:29

Yes, please take it apart and trace.

I have not found any schematics on the web for this pedal.
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Re: Mad Professor 1

Postby FuzzMonkey » 09 May 2017, 22:16

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Re: Mad Professor 1

Postby howmuch » 02 Jun 2017, 18:07

rmroza wrote:... I may take this apart and trace it completely to understand the design.


It would be excellent if you did. :applause:
And if you need any help, just give us a shout.
That pedal sounds really good.

rmroza wrote:... I wonder if say the Mighty Red Distortion pedal is the same distortion ...


Not sure if the Mighty Red Distortion is the same as the BJF/Bearfoot Dyna Red Distortion, but it probably is, so looking at the schematic here :
http://revolutiondeux.blogspot.co.uk/2009/05/bjf-dyna-red-distortion.html
the Dyna Red only has one op-amp and one JFET, so it's probably quite different.
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Re: Mad Professor 1

Postby BJF » 04 Jun 2017, 08:48

Hi there,

I can say this, that if you read the product text it says the circuit has two overdrive stages. MP was not keen on my designing a circuit like this from ground up….though I might have preferred to, but they preferred I’d use building blocks from proven designs I had made.
The circuit uses a low level, slow slope expander to minimize noise…and you might also then figure that the absolute forte of AD797 is ultra low noise….there are a number of noise reducing tricks used through out circuit- note that you can derive the envelope of a signal, for expansion detection from a point where signal is strong and not necessarily from the output of circuit.
There were problems with the 2000 first produced units ranging from one transistor stage being biased wrongly to expander being hooked up in three different ways all being wrong but in latest iteration of ONE all parts of circuit should be hooked up correctly and with the latest iteration you should be able to get a good representation of the intended sound through a clean amplifier and the noise reduction circuits should allow you to get this sound at a rather loud level without excess noise and if all parts are hooked up correctly in the circuit you should also be able to turn down volume control on guitar for a less distorted sound without hick ups from expander or dead band response from any of the stages.

There is a built in reverb supplied by the internal FV-1, much because this sound intended craves reverb to sound authentic. Now you can certainly write a custom algorithm onto the FV-1 itself without having to store it in an external memory and that saves pcb space- however my digital designer was not involved in the development of ONE and neither in any MP product much because his views on the Red Cable- therefore there are no digital designs made by BJF for MP.

Typically when designing heavily saturated distortion cascaded stages show the best noise performance and multiple distortion knees can certainly aid dynamics of distortion even in a highly saturated circuit.

Important for the authenticy of this sound is the processing of treble and as a side note of this I know a technician in Florida that collects waveforms at the output of amplifiers as a signature of sound from various artists and he has a rather extensive library of such waveforms-it follows that exact eq is a vital part of signature.

The Treble control of ONE can fairly easily be rewired into a three band T-type eq as a hint for anyone who wants to rebox ONE and extend controls.


At your service
BJ
BJF Electronics

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howmuch (04 Jun 2017, 15:37), mojah63 (07 Jun 2017, 18:56)
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Re: Mad Professor 1

Postby howmuch » 04 Jun 2017, 15:37

Hi BJ,

Thank you for your generous input here and elsewhere on this forum. Always a great insight.
I don't suppose you could talk us through your aims as you went through the design process, in terms of distortion/harmonic characteristics and that all important EQ that you mentioned.
Could you explain the EQ needed to get this particular sound?

BTW - Great job on this pedal.

Thanks
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Re: Mad Professor 1

Postby modman » 06 Jun 2017, 11:56

Fanboy paradise again?
"The whole point of diy is diy. It's not dsoiyathodtr - do some of it yourself and then have others do the rest" (paulc)
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Re: Mad Professor 1

Postby howmuch » 20 Jun 2017, 15:52

rmroza wrote:Stay Tuned!


Yep, still tuned...

If you've changed your mind, any chance of some gutshots?
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Re: Mad Professor 1

Postby modman » Yesterday, 09:19

That's why BJ posts here, to try and keep off the member from tracing.
Probably the guy is contacted in pm not to publish.
"The whole point of diy is diy. It's not dsoiyathodtr - do some of it yourself and then have others do the rest" (paulc)
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