Böhm- Trickverzerrer

SonicDaeath · Post by **SonicDaeath** » 31 Mar 2012, 21:40

I could have sworn there was a thread devoted to this pedal, but after using the the search function I could not find it.

Factory schematic:

Attached is an unverified vero layout I made. Any feedback would be appreciated!

sinner · Post by **sinner** » 31 Mar 2012, 21:45

Hey, I love it! Thanks a lot. I never heard about that one.

SonicDaeath · Post by **SonicDaeath** » 01 Apr 2012, 02:21

Yeah I'm curious to see what it sounds like. I think maybe I saw Discofreq post something about it somewhere else... anyways, its an East-German fuzz pedal.

LucifersTrip · Post by **LucifersTrip** » 01 Apr 2012, 04:46

thanx for posting that one. I'll have to search German sites for more info. Do you have any idea around what year it is from?

Yeah...If the transistors are 2SC206/2SC207, they are silicon and it looks like the diode is germanium:
http://english.electronica-pt.com/db/cr ... ?ref=GA102

odd .22 electro input

what's R6?

cool...will save for future breadboard

LucifersTrip · Post by **LucifersTrip** » 01 Apr 2012, 04:51

any idea what the first 3 pots are named? does it say Q3C voltage .1 - 5v?

DiscoFreq · Post by **DiscoFreq** » 01 Apr 2012, 05:52

Nice, I have about 5 of those (I had more but gave away 1 or 2), they sound quite good and you have a lot of options with the 2 knobs and 2 trimpots

LucifersTrip · Post by **LucifersTrip** » 01 Apr 2012, 06:57

DiscoFreq wrote:Nice, I have about 5 of those (I had more but gave away 1 or 2), they sound quite good and you have a lot of options with the 2 knobs and 2 trimpots

is it in your database?

roseblood11 · Post by **roseblood11** » 01 Apr 2012, 07:44

LucifersTrip wrote:
DiscoFreq wrote:Nice, I have about 5 of those (I had more but gave away 1 or 2), they sound quite good and you have a lot of options with the 2 knobs and 2 trimpots
is it in your database?

http://www.effectsdatabase.com/model/bohm/verzerrer

sinner · Post by **sinner** » 01 Apr 2012, 08:12

roseblood11 wrote:
LucifersTrip wrote:
DiscoFreq wrote:Nice, I have about 5 of those (I had more but gave away 1 or 2), they sound quite good and you have a lot of options with the 2 knobs and 2 trimpots
is it in your database?
http://www.effectsdatabase.com/model/bohm/verzerrer

I have this pedal in my basement! Funny...

I never plug it in, as it have odd input/output sockets and I was to lazy to rewire it

I'll make few gutshots when I find it

LucifersTrip · Post by **LucifersTrip** » 01 Apr 2012, 11:52

sinner wrote:
roseblood11 wrote:
LucifersTrip wrote:
DiscoFreq wrote:Nice, I have about 5 of those (I had more but gave away 1 or 2), they sound quite good and you have a lot of options with the 2 knobs and 2 trimpots
is it in your database?
http://www.effectsdatabase.com/model/bohm/verzerrer

I have this pedal in my basement! Funny...

I never plug it in, as it have odd input/output sockets and I was to lazy to rewire it

I'll make few gutshots when I find it

thanx...I did a search and got no results...weird. I see the odd jacks. not 1/4". The enclosure is very unique also...and the circuit doesn't look like a direct copy of anything either? good to see something somewhat original

sinner · Post by **sinner** » 01 Apr 2012, 12:02

As far as I remember the in/outs are done on those old-shit 5 pin connectors that was everywhere here and in NRD during communism days, and there was no room to change it to 1/4" jacks. I definitely will open it up, will took shitload of picts and compare to the schemo posted earlier

roseblood11 · Post by **roseblood11** » 01 Apr 2012, 19:03

LucifersTrip wrote:any idea what the first 3 pots are named?

P1= "Verzerrung" / Drive,Gain etc
P2= "Empfindlichkeit" / Sensitivity
P3= "Höhenanteil" / Treble,Tone
P4="Lautstärke" / Volume

LucifersTrip · Post by **LucifersTrip** » 01 Apr 2012, 19:25

roseblood11 wrote:
LucifersTrip wrote:any idea what the first 3 pots are named?
P1= "Verzerrung" / Drive,Gain etc
P2= "Empfindlichkeit" / Sensitivity
P3= "Höhenanteil" / Treble,Tone
P4="Lautstärke" / Volume

cool...if the schematic notes weren't and image I would've cut & pasted into a translator

that definitely helps..thanx

SonicDaeath · Post by **SonicDaeath** » 02 Apr 2012, 05:00

The East-German connection piqued my interest.

sinner · Post by **sinner** » 04 Apr 2012, 20:46

Ok, got it. Usually when I'm looking for something in my basement I'm finding shit (or things I was looking for months earlier)

It's dark outside so it's pointless to do picts now, I'll wait till tomorrow, and I do nice ones in daylight.

Mine is not branded as Böhm, it says Veb Musikelektronik and the model simply says Verzerrer (or opposite).

It may be different unit as well, I haven't compare it to the schemo yet, I do that also tomorrow

sinner · Post by **sinner** » 04 Apr 2012, 20:50

roseblood11 wrote:
LucifersTrip wrote:any idea what the first 3 pots are named?
P1= "Verzerrung" / Drive,Gain etc
P2= "Empfindlichkeit" / Sensitivity
P3= "Höhenanteil" / Treble,Tone
P4="Lautstärke" / Volume

Yeah, it must be different model, or something...

Controls on mine are:
-Pegel
-Diskant
-Intensität
-Empfindlichkeit

grrrunge · Post by **grrrunge** » 05 Apr 2012, 00:18

sinner wrote:Controls on mine are:
-Pegel
-Diskant
-Intensität
-Empfindlichkeit

Those are level, treble, intensity and sensitivity

in case you didn't already know...

Post by **digi2t** » 07 Apr 2012, 22:58

OK, I've made the recording below. Q1 is a BC109, and Q2 - 3 are BC639's. The diode is a 1N270. I was VERY surprised by the result. As a matter of fact, I had ordered the BC639's for something, but I can't recall what exactly right now

. They sure sound good in here though.

Here are the hfe readings for the trannies, as per my Wavetek Meterman DMM;

Q1 = BC109 - hfe 201
Q2 = BC639 - hfe 131
Q3 = BC639 - hfe 129

I have 3.5v on Q1E, 4.5v on Q2E (adjusted via 50K trimmer, replacing 47K resistor), and Q3C is set to 0.1v (via P2) with guitar plugged in, guitar volume on 10, hand muting strings, (and all flourescent lighting within sight OFF!

).

I'm recording directly into a BOSS BR-600, no added effects. Guitar is a Dillion Korina Explorer, GFS Dream 180 bridge pup. I'm going from minimum drive, and bass, mid, and treble tone. Then 1/2 drive, bass, mid, treble. Finally, full drive, bass, mid, treble.

http://www.soundclick.com/player/single ... 57776&q=hi

Sounds like a fuzz monster to me!

Post by **digi2t** » 09 Apr 2012, 00:31

I've done a bass track with the fuzz, so here it is. Same circuit as the guitar track, .22uF input cap.

Same play as the guitar track, low, medium, high gain, turning up the tone through each gain stage.

Bass is a Schecter 5 string, EMG Hi-Z pups (both on, onboard EQ set flat), fuzz, BOSS BR-600 (no added effects).

My profuse apologies for my crappy bass playing. Not my instrument by any stretch of the imagination

http://www.soundclick.com/player/single ... 60147&q=hi

Goes from ultra low velcro, to real buzz-saw. Me like .

Enjoy.

Post by **digi2t** » 09 Apr 2012, 17:08

Alrighty, here's a vero;

There is a vero already above (E. Coffey), but right off the bat I noticed an error on that one. So, I drew up another one. Slighty bigger, but I made room for a larger power rail cap (up to 1000uF if necessary), and protection diode. Also, there's some extra room if one wishes to mess around in the clipping diode area. Made the 47K resistor a trimmer as well, for fine tuning the voltage at Q2.

The tone pot can also be sub'd for a 50K in a pinch. I've tried both, and the audible difference is minimal.

Just beware is you're going to use different trannies in the Q2 / Q3 slots. BC639's are ECB pinout. You've been warned.

As always, unverified until built, and please let me know if anyone notices an error.

Böhm- Trickverzerrer [schematic]