There is nothing mystic about this amp, it’s pure magic…

Preamp distortion and/or Power-amp distortion, with or without compression at any volume level.

Three (3) gain structure options (Normal, Abnormal/Tube and Abnormal/FET).

Four (4) different ways to adjust the ever critical treble response.

Foot-switches for FET and adjustable Boost.

Extensive tone control network (with Focus and Tonebalance)

Series effect loop with level options

Dynamics you have never experienced.

Magical BJF circuit.


Totally hand made, point to point wired 40-75W tube amp that is fine-tuned for the best possible tone.

Based on the 20 years experience working with finest tubes amps.

The circuit is as original as a tube amp can be, respecting the heritage of the greatest amps designs. The fine-tuned circuit with build in bias adjustment accepts 6L6, EL34, KT77, KT66, KT88, 6550 … even 6V6 if you can find ones that can handle 500V of plate voltage.

The overbuild custom made transformers have enough juice to drive the KT88’s/6550’s to about 75W of power.

With special POWERSUCK switch you can drive the power-amp to fat compressed tone at bedroom levels.

We are not talking about 3-dimensional tone, this one is a 4-D tone! And the touch response is awesome, this is about the most dynamic amp there is. There are tones from sparkling clean to fat and sweet, singing overdrive, from sparkle to rumble… ALL the parts are overrated and should last for ages. The amp is available factory direct by custom order only and it can be played all over the world (100/117/230/240V)

The real beauty is in the amp circuit that is a piece of art.

Lot of special tuned circuits where the placement of components and length of wires makes a difference in tone.

Mad Professor has FOUR ways to control the critical treble response:

FOCUS switch has two options with slight treble boost, then there is

TONE BALANCE that you can adjust treble with, the

TREBLE control of course adjust certain Treble frequency and the

PRESENCE controls another Treble frequency.

You will find the optimal Treble response with any guitar and cabinet using these controls.

Even the clean tone you hear on a guitar amp has distortion. You hear it as shimmer, sparkle, twang etc. To hear a totally clean guitar tone plug to your home stereo and enjoy.

You can get distortion from each input (NORMAL, ABNORMAL at tube setting and ABNORMAL at FET setting).
You can footswitch between the TUBE and FET setting when you are plugged into ABNORMAL input and the TUBE/FET switch is turned to FET position.

You can have distortion from Preamp or from Power-amp, you can have it at lower volume levels with the special POWERSUCK switch.

There are lot of different distorted tones from this amp: “clean”, sweet, crunchy, fat, “On the edge”, singing, dynamic, with powertube saturation or without.. You can tailor the distortion so that treble distorts earlier than the low-end etc….

The amp is LOUD but has also great tone at club-levels thanks to special BJF design “POWERSUCK” option.

Inside the amp

There are bias test points behind the back panel and you set the bias for the different tubes by using just a normal Volt meter.
A Bias switch to switch between Hi and Low bias for EL34 or other types of tubes.
Wide range bias trimmer to set the bias for different tubes.
It takes only few minutes to change the power tubes and you can do it yourself.

Design philosophy

All parts are deliberately overrated to ensure reliable and safe operation.
Circuit is to be as far as possible original or at least nonstandard.
Construction should be neat and build to last. It should be the best amp ever built.
It must be an inspiring amp to play!!!

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