OMG Fuzz Version 1

[WhiskeyMadeMeDoIt]

I have had a few days of experimentation and breadboarding success.
After much part switching, jamming, whiskey, and good old fashion luck I present you with a new fuzz.
This fuzz has been tested by another member named CozyBuilder.
I was very fortunate that he was not only willing to try it but he offered feedback, suggestions, and a vero layout for this circuit.
The name "OMG Fuzz" is also from CozyBuilder! It stands for One Mighty Gnarly Fuzz.
This circuit is a way point for another design. It started with this and grew into something else which i will post as version 2.
It's a nice little fuzz and has some good sounds be sure to fire up a soldering iron and give it a whirl.
No demo yet for this one because its off the board for version 2.
The vero's haven't been verified yet but i will be building them and verifying soon unless someone beats me to it.
Be sure to look for the version 2. Coming soon...

The circuit:


The true bypass version:


CozyBuilder sent me hand drawings of his layout so if there are mistakes it's probably mine when I converted it in DLC.
The millenium bypass version from CozyBuilder:

[Cozybuilder]

Mine has a lot of bite to it, tons of sustain, a fun pedal! You can turn the gain down all the way and have a decent overdrive- this has an incredible amount of volume on tap. Unity is about 9:00, with the gain all the way down, about 7:30 with the gain pegged. Turn up the gain and its a whole new pedal.

In my build, the coupling caps between Q1-Q2 and Q2-Q3 are changed from 100nF to 10nF. You should play with these values to suit your taste, 22nF knocks off a lot of treble. This build uses standard 16mm Alpha pots, ¼ watt resistors, poly film caps, and has an additional 220pF filter cap paralleling the 100uF cap.

[Cozybuilder]

I changed 2 of the coupling caps (from 10nF to 22nF and 33nF), the gain pot (from B100K), and am very happy with the sound now- meaty, gnarly, tons of sustain at max gain, great overdrive at minimum gain, completely usable pot travel. The volume is incredible, you definitely want to start at the low end of the scale.

[Cozybuilder]

Heres a VERO version of the OMG Fuzz, with switchable diode, and tone control. The range of sounds it covers is incredible, from ultra clean with the Germanium diode at minimum grit, to great 60's grinding fuzz tones, to metal with incredible sustain. The tone circuit is simple as could be, and surprisingly effective. This build uses standard 16mm pots, miniature SPDT switch, 1/4W metal film resistors, film box caps, 16V electrolytic cap, Millennium bypass switch. The board is mounted on ½" standoffs.



gut shot



back of card



Schematic

[Cozybuilder]

Heres the vero layout:



and box layout:

[Luke51411]

3 16mm pots and an spdt in a 1590A 
Much props. Very nice work.

[bluebunny]

3 16mm pots and an spdt in a 1590A 

Nah.  Photoshop.   

[WhiskeyMadeMeDoIt]

Russ does some unbelievable 1590a builds.  He has an abductor delay he is working on    in a 1590a !? Amazing is an understatement. 

[bluebunny]

Russ does some unbelievable 1590a builds.  He has an abductor delay he is working on   in a 1590a !? Amazing is an understatement.  

You're not wrong.  He's not "Cosybuilder" for nothing!    

[duck_arse]

gah!

with an external nut dc socket, maybe a fourth pot? very nice. can I see a pic with the plugs in plugged?

[Luke51411]

gah!

with an external nut dc socket, maybe a fourth pot? very nice. can I see a pic with the plugs in plugged?

Or the low profile dc jack like BLMS sells, you could put that under the LED possibly. Madness 

[samhay]

Seeing as were are way off-topic...

You can get 4 16mm pots into a 1590A with a regular DC jack and a 3PDT without too (I use this liberally) much trouble.
You can't see them, but there are 4 pots under the board in here: http://www.diystompboxes.com/smfforum/index.php?topic=102172.msg904975#msg904975

What blew my mind was where Russ put a Belton BTDR-2 reverb brick in one of these!
http://www.diystompboxes.com/smfforum/index.php?topic=105109.msg971201#msg971201

[Cozybuilder]

Very happy to see this thread is being read- the circuit is worthy of a tryout.

@Sam- I hadn't seen your Decompression Overdrive- it looks interesting, and I look forward to breadboarding it- will probably build it too (I've got to try 4 16mm pots  )

[Cozybuilder]

@ DA: Here are a couple of close-up shots of the next build- jack holes are in the same location: Note that the sleeve connection tab is nipped from the input, and the output is the on/off.

[duck_arse]

cozy - as rg says somewhere else, if all your pedals are external dc supply, why have an on/off jack switching? you could *save* some space with a pair of monos, no?

I use x-wings on my builds, so that's a bit more space in my box gone. that and the home-made, hand-bent with the wood and the extra brackets and all, and my crap measure, hit, drill process means I'd never be able to do fits like yours.

cases with fixed dimensions? luxury!

[Cozybuilder]

You are right! So obvious now that its been pointed out. A 4-16mm pot pedal is now a priority.

Re hole accuracy, some of my earlier builds were embarrassing, lots of drill bit wander . The old (50yrs+) drill press was well worth repairing.

[samhay]

@Sam- I hadn't seen your Decompression Overdrive- it looks interesting, and I look forward to breadboarding it- will probably build it too (I've got to try 4 16mm pots  )

Probably best to consider this a circuit snippet rather than a finished product. It really needs some filtering/tone control and the 'decompression' and 'asym.' controls are possibly too interactive to warrant both of their inclusion. Worth a play with on the breadboard though.

[Cozybuilder]

How about a small box build?

Same circuit as the Vero build above with choice of blue LED or Ge (1N34a) clipper, and tone control, in a 1590LB box. It sounds just like the Vero build.



Guts:



Definitely smaller than a 1590A, but still a usable size.

[bluesdevil]

Hats off to you guys using the small boxes.... absolutely sick! Those pics are enough to inspire me to give a try one day soon.
About time to ween myself off my beloved 125-B.

[Plexi]

Looks very very interesting... I should give it a try 
 

Bump for this great looking fuzz!