McCrypt AT2 Distortion (Krank Maximus style clone) Schematic  [schematic]

A forum devoted to mod, tips and suggestions for upgrading and rehousing your VERY CHEAP commercial stompbox to near boutique excellence.

McCrypt AT2 Distortion (Krank Maximus style clone) Schematic

Postby Manfred » 09 Aug 2017, 22:51

"McCrypt" is an company label of the German distributer Conrad.
I bought the pedal at a favourable price.
I was thinking the pedal is defective, because it was bad sounding,
rather like a fuzz.
The schematic was not available at Conrad, therefore making it necessary to trace the circuit.
finally it is a Krank Maximus style Clone.
The reason for the bad sounding was the wrong biasing of the transistor input stage,
the output signal became heavily asymmetrical distorted at low input signal levels.
You can find the read DC-voltages on the schematics.
I increased the the value of R6 from 100 Ohms to 470 Ohms and made some further component changes
according the Krank Maximus and ProTone Pedals Body Rot II schematic.
It sounds great now.

Mc1.jpg


McCryptAT2ComponentSide.jpg


McCryptAT2SolderSide.jpg


McCrypt AT2 Distortion modded Schematic.JPG


McCrypt AT2 Distortion Schematic.JPG


McCrypt AT2 Distortion Mods.JPG


Shot with all the changes:
Mc2.jpg
You do not have the required permissions to view the files attached to this post.
Manfred
Resistor Ronker
 
Posts: 400
Joined: 05 Apr 2009, 00:42
Has thanked: 706 times
Have thanks: 300 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem  [schematic]

Postby Nocentelli » 10 Aug 2017, 00:33

:applause:


Why no thank button :scratch:
mmolteratx wrote:absolutely zero commercial use allowed. If I find anyone selling these, I'll fly to your house and kick you in the nads. And you may or may not find yourself in trouble.
User avatar
Nocentelli
Tube Twister
 
Posts: 2027
Joined: 09 Apr 2009, 08:06
Location: Leeds, UK
Has thanked: 770 times
Have thanks: 771 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem

Postby Manfred » 10 Aug 2017, 07:04

Nocentelli wrote::applause:


Why no thank button :scratch:


It's free! :)

I would have loved to buy one more pedal, but it is sold out in the moment.
Manfred
Resistor Ronker
 
Posts: 400
Joined: 05 Apr 2009, 00:42
Has thanked: 706 times
Have thanks: 300 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem

Postby bool » 10 Aug 2017, 13:05

Man, that "tone" section just dosen't make any sense to me.

From a quick calc, it seems that the scoop is centered around 110Hz (slightly bellow actually), which is rather low imho.

If you replace that 100nF cap with a 22nF; and the 10K resistor with a 4K7; you should get more in the 340Hz-ish territory which is imho more appropriate. (untested)
bool
Breadboard Brother
 
Posts: 74
Joined: 01 Feb 2008, 02:06
Has thanked: 0 time
Have thanks: 11 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem

Postby Manfred » 10 Aug 2017, 16:39

bool wrote:Man, that "tone" section just dosen't make any sense to me.

From a quick calc, it seems that the scoop is centered around 110Hz (slightly bellow actually), which is rather low imho.

If you replace that 100nF cap with a 22nF; and the 10K resistor with a 4K7; you should get more in the 340Hz-ish territory which is imho more appropriate. (untested)


Thanks for the hint, I will make first a test by circuit simaulation.
Manfred
Resistor Ronker
 
Posts: 400
Joined: 05 Apr 2009, 00:42
Has thanked: 706 times
Have thanks: 300 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem

Postby POTL » 11 Aug 2017, 22:47

Strange schematic :mrgreen:
The capacitor 470n is clearly superfluous
Input resistance about 37K :shock: :slap:
I do not even want to take a day off
At a minimum, input and output buffers are needed
Tone control is terrible
:applause:
POTL
Solder Soldier
 
Posts: 194
Joined: 26 Sep 2016, 04:11
Has thanked: 41 times
Have thanks: 43 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem

Postby Manfred » 13 Aug 2017, 17:51

input resistance about 37K :shock: :slap:
I do not even want to take a day off
At a minimum, input and output buffers are needed


It is the same input circuit which is applied on the Krank Distortion Maximus and the ProTone Pedals BodyRotII Pedal,
both Pedals work fine.

Tone control is terrible

Ok, it could be much better but it works not too bad.
It is a mid notch filter with a center frequency of about 100Hz.

McCryptToneControlFrequencyResponse.jpg
You do not have the required permissions to view the files attached to this post.
Manfred
Resistor Ronker
 
Posts: 400
Joined: 05 Apr 2009, 00:42
Has thanked: 706 times
Have thanks: 300 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem

Postby bool » 14 Aug 2017, 11:56

Theres a slight contradiction in "mid-notch filter" and "center frequency about 100Hz".

As I suggested for this style pedals imho it would be worth upping the "mid-notch" to somewhere around 330-350Hz. But hey...
bool
Breadboard Brother
 
Posts: 74
Joined: 01 Feb 2008, 02:06
Has thanked: 0 time
Have thanks: 11 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem

Postby Manfred » 18 Aug 2017, 20:46

bool wrote:Theres a slight contradiction in "mid-notch filter" and "center frequency about 100Hz".

As I suggested for this style pedals imho it would be worth upping the "mid-notch" to somewhere around 330-350Hz. But hey...


You are right.
Manfred
Resistor Ronker
 
Posts: 400
Joined: 05 Apr 2009, 00:42
Has thanked: 706 times
Have thanks: 300 times

Re: McCrypt AT2 Distortion (Krank Maximus style clone) Schem

Postby bool » 19 Aug 2017, 17:13

You can testdrive how the freq. change suits the pedal by simply (temporary) changing the 10k res. in the stack to 1k (parallel something to it f.e. a 1.1k resistor)

The eq curve wont be ideal, but massaging the eq usually takes time.
bool
Breadboard Brother
 
Posts: 74
Joined: 01 Feb 2008, 02:06
Has thanked: 0 time
Have thanks: 11 times


Return to Pimp-My-Cheap-Pedal

Who is online

Users browsing this forum: No registered users and 9 guests