Univox - Superfuzz  [schematic]

Discussion regarding early stompbox technology: 1960-1975 Please keep discussion focused and contribute what info you have...
drewl
Breadboard Brother
Posts: 105
Joined: 11 Feb 2010, 15:56
Been thanked: 5 times

Post by drewl »

Mouser, that makes sense.

I found a bunch of 1N34's in a drawer at work with some other odd stuff like round can 741's.
Didn't think they could be that old, but they do sound really good.

User avatar
tabbycat
Cap Cooler
Posts: 518
Joined: 03 Jul 2011, 01:09
Completed builds

completed builds: shinei univox 6tr superfuzz with mods, vox repeater, earth sound research graphic fuzz, roland ad-50 double-beat fuzz, shinei fy-2 companion fuzz with mods, ampeg scrambler, fender blender, ep3 18v pre, dam meathead fuzz, coloursound inductorless wah, lpb1.
mods: joyo voodoo octave cap rotation, dan echo r10 mod, pb&j r10 mod, behringer vintage phaser true bypass mod, behringer sf300 superfuzz diode switch (germanium-silicon).
vero layouts: earth sound research graphic fuzz (posted here).

Location

i could tell you but i'd have to kill you.

Has thanked: 213 times
Been thanked: 55 times

Post by tabbycat »

Ok. ok. ok. ok…..

Just spent a good hour (or two) reading and rereading this completely fascinating thread.
Am a psychocandy-sound obsessive. Which could easily be cured with a Shin-ei fuzz-wah. Alas I’m also one of those fashionable public sector redundancy statistics, so £150 for a Shin-ei is a wet dream too far for my finances at the moment. If at all.
Have never built a pedal. Can just about solder new pots and pickups into guitar bodies, but have never done anything with a circuit board.

But am up for trying for two big reasons.
a. I REALLY want one.
b. I bought a great Behringer vintage tube distortion after seeing a great youtube demo by Mike Livesley. I love that overdrive pedal, so respect his judgement a lot. Was pretty damn surprised to see him pop up here and feel pretty encouraged that if he is responsible for the schematic I might not totally destroy all the bits and end up with a solder snowball.

Anyway, have got a couple of retard-level newbie questions if anyone is feeling charitable enough to indulge a first timer…?

Where’s the best place to buy these bits online? (I’m in Hastings in the UK).
On Mike’s schematic I’ve guessed that R = Resistor, C= Capacitor and Q = Transistor. But what is D?
What kind and rating of pots and switches do I need? Am confused by spst, spdt and dpdt? I really like Graemeys two footswitch version (one for on/off, one for Tone 1/Tone 2) which sounds REALLY good in the youtube clip. So I’m going for that set up.
What’s the difference between Mike’s 2SC828 transistors and Graemey’s 2N3904? (Graemey’s sounds great but don’t know if Mike’s sounds better or worse as haven’t heard it).

Many thanks to anyone who can spare a minute to answer one or some of my questions. I know they sound like questions beneath asking for people with some electronic experience but I’m just starting.

Thanks a lot Stompers!
Cat :)
"be a good animal, true to your instincts" (d.h. lawrence).
"there is no excellent beauty that hath not some strangeness in the proportion" (francis bacon).
"ni dieu ni maître" (anarchist slogan).

User avatar
tabbycat
Cap Cooler
Posts: 518
Joined: 03 Jul 2011, 01:09
Completed builds

completed builds: shinei univox 6tr superfuzz with mods, vox repeater, earth sound research graphic fuzz, roland ad-50 double-beat fuzz, shinei fy-2 companion fuzz with mods, ampeg scrambler, fender blender, ep3 18v pre, dam meathead fuzz, coloursound inductorless wah, lpb1.
mods: joyo voodoo octave cap rotation, dan echo r10 mod, pb&j r10 mod, behringer vintage phaser true bypass mod, behringer sf300 superfuzz diode switch (germanium-silicon).
vero layouts: earth sound research graphic fuzz (posted here).

Location

i could tell you but i'd have to kill you.

Has thanked: 213 times
Been thanked: 55 times

Post by tabbycat »

graemey wrote:https://uk.youtube.com/watch?v=BPBn1VK8C ... annel_page


Finally got round to posting a youtube video of my Superfuzz.
Big thanks to Shortscalemike for the vero layout and, as you may see, I pinched the 'Starve' control idea also. :applause:

I used 2N3904 trannys in mine.

Check the link above. Fuzzchaos!
Graemey, your pedal sound The Sh*t! really bad-good. thanks for the demo and congrats on a killer build ;)
"be a good animal, true to your instincts" (d.h. lawrence).
"there is no excellent beauty that hath not some strangeness in the proportion" (francis bacon).
"ni dieu ni maître" (anarchist slogan).

User avatar
noelgrassy
Resistor Ronker
Posts: 388
Joined: 28 Nov 2007, 03:43
my favorite amplifier

MOTS Magnatone & Trainwreck

Completed builds

Tonebender Mk II w/ 3 OC75's, Burns BuzzAround w/NKT 275,Rangemaster w/ OC44, Fuzz Face w/ SKS363's, CJOD, Harmonic Percolator w/2N404A & 2N3635(vintage correct box,sliding pots, 1%glass resistors),Stack-O-Dimes & Whipple Wahs,

Location: Vacuum Tube Valley, Cali
Has thanked: 11 times
Been thanked: 3 times

Post by noelgrassy »

tabbycat wrote:Ok. ok. ok. ok…..

Just spent a good hour (or two) reading and rereading this completely fascinating thread.
Am a psychocandy-sound obsessive. Which could easily be cured with a Shin-ei fuzz-wah. Alas I’m also one of those fashionable public sector redundancy statistics, so £150 for a Shin-ei is a wet dream too far for my finances at the moment. If at all.
Have never built a pedal. Can just about solder new pots and pickups into guitar bodies, but have never done anything with a circuit board.

But am up for trying for two big reasons.
a. I REALLY want one.
b. I bought a great Behringer vintage tube distortion after seeing a great youtube demo by Mike Livesley. I love that overdrive pedal, so respect his judgement a lot. Was pretty damn surprised to see him pop up here and feel pretty encouraged that if he is responsible for the schematic I might not totally destroy all the bits and end up with a solder snowball.

Anyway, have got a couple of retard-level newbie questions if anyone is feeling charitable enough to indulge a first timer…?

Where’s the best place to buy these bits online? (I’m in Hastings in the UK).
On Mike’s schematic I’ve guessed that R = Resistor, C= Capacitor and Q = Transistor. But what is D?
What kind and rating of pots and switches do I need? Am confused by spst, spdt and dpdt? I really like Graemeys two footswitch version (one for on/off, one for Tone 1/Tone 2) which sounds REALLY good in the youtube clip. So I’m going for that set up.
What’s the difference between Mike’s 2SC828 transistors and Graemey’s 2N3904? (Graemey’s sounds great but don’t know if Mike’s sounds better or worse as haven’t heard it).

Many thanks to anyone who can spare a minute to answer one or some of my questions. I know they sound like questions beneath asking for people with some electronic experience but I’m just starting.

Thanks a lot Stompers!
Cat :)
Howdy,
#1] D stands for diode, Dad.

#2] The initials SPST= single pole, single throw
DPDT= double pole, double throw[throw being the pole being switched in & out with the normally connected pole.
to answer your query about xistor sounds is pretty much a subjective choice than a specific sound. So download some
data sheets on these xistors to compare Mfgr's operating specs.. A 2N3904 is a currently made kine and I think finding
the 2SC828 will be tougher depending on your sources. I'm not sure though.
I'm in the US so I can't comment on local suppliers in your domain. Perhaps some of the locals will advise... :horsey:
Noel Grassy.
Copyright does not protect facts, ideas, systems, or methods of operation, although it may protect the way these things are expressed. US Copyright Office

User avatar
JustinFun
Posts: 39
Joined: 22 May 2010, 15:17
Has thanked: 8 times
Been thanked: 11 times

Post by JustinFun »

noelgrassy wrote: I'm in the US so I can't comment on local suppliers in your domain. Perhaps some of the locals will advise.
I can heartily recommend Doctor Tweak's store (doctortweak.co.uk) for all pedal-related stuff. Also, the guy who runs it is really helpful and friendly.

For generic, low-value stuff like resistors I tend to use bitsbox.co.uk

I think both of these came from recommendations here!

B3ar
Breadboard Brother
Posts: 100
Joined: 24 Jan 2010, 17:11
Has thanked: 28 times
Been thanked: 1 time

Post by B3ar »

Is there an "octave off" switch mod worth doing?

User avatar
tabbycat
Cap Cooler
Posts: 518
Joined: 03 Jul 2011, 01:09
Completed builds

completed builds: shinei univox 6tr superfuzz with mods, vox repeater, earth sound research graphic fuzz, roland ad-50 double-beat fuzz, shinei fy-2 companion fuzz with mods, ampeg scrambler, fender blender, ep3 18v pre, dam meathead fuzz, coloursound inductorless wah, lpb1.
mods: joyo voodoo octave cap rotation, dan echo r10 mod, pb&j r10 mod, behringer vintage phaser true bypass mod, behringer sf300 superfuzz diode switch (germanium-silicon).
vero layouts: earth sound research graphic fuzz (posted here).

Location

i could tell you but i'd have to kill you.

Has thanked: 213 times
Been thanked: 55 times

Post by tabbycat »

thanks to NoelGrassy and JustinFun for the suggestions :thumbsup

went with Doctor Tweek. easy to use site and bits arrived superquick. very positive experience.

my maplin 50w adjustable temp soldering iron arrived today (£15 cheap new from ebay) and, as i've got a cold sore and feel very unkissable, i'm staying in tonight and might have a blast later. actually worried about the fumes stinking out my bedroom though. probably not healthy, so may do it in the garden tomorrow. if it ever stops raining.

have got all the bits. have drilled out the breaks in the vero board and threaded in the 10k resistors just to get my bearings.
so next step is to learn how to solder neatly and within the lines, then get on with it. will report back soon.

think the only question i still have is how do the balance and expander pots, switch (basic plastic slidey one) and footswitch (3pdt as i want an led to tell me when it's on) attach to the circuit board?
the schematic i'm using doesn't show that in a way i can understand (verified version by ShortScaleMike at bottom of page two of this thread https://www.freestompboxes.org/viewtopic.ph ... 4&start=20).
it seems to be something that should anyone who knows what they're doing will instantly appreciate. but i'm not that smart yet.
any hints would be much appreciated.

thanks and have a great weekend all,

Cat :)
"be a good animal, true to your instincts" (d.h. lawrence).
"there is no excellent beauty that hath not some strangeness in the proportion" (francis bacon).
"ni dieu ni maître" (anarchist slogan).

amp_surgeon
Posts: 25
Joined: 05 Jul 2011, 19:59
my favorite amplifier: 1955 Gibson GA30
Been thanked: 28 times
Contact:

Post by amp_surgeon »

B3ar wrote:Is there an "octave off" switch mod worth doing?
Sure. You'll need a DPDT switch. One pole should break the connection between the wiper of the expander pot and the electrolytic on the base of the 3rd transistor (the phase splitter). The other pole should break the connection between the tied collectors of the 4th and 5th transistors (the differential amp) and the electrolytic just before the germanium clipping diodes.

Code: Select all

              "Expander" pot wiper <---*   *---> "-' side of electrolytic on base of 3rd transistor
                                        \
                                         \
                                          *-+
                                            |
                                       *----+
                                        \
                                         \
collectors 4th and 5th transistors <--*   *---> "+" side of electrolytic before Ge diodes
Sorry if this is a little difficult to make out. The asterisks are the switch lugs. The upper three are the first pole, and the lower three are the second pole.

From my own measurements, if you've got 500mV going into the pedal, and you've got the "Expander" turned all the way down, then you'll have about 250mV going into the base of the third transistor - the phase splitter, and almost 500mV at the collectors of the fourth and fifth transistors - the differential amp. If you turn the "Expander" up much at all then the diodes begin to conduct, and the signal will be clipped, so this is the only level where you get to see the real difference between the signal amplitudes. What does this mean? Well, it means the signal going into the clipping diodes will only be about half what it would normally be when the "Expander" pot is at minimum and the octave circuit is bypassed. You'll need to turn the "Expander" pot a bit more clockwise than normal before you'll start to get some clipping. There should still be plenty of headroom in the range of the "Expander" pot since the output of the second transistor is over 4V, and this is what will be going into the clipping diodes when the "Expander" pot is dimed. The max volume should be the same, since it's limited by the clipping diodes.

Caveat: I've never actually put this mod in a pedal. I've only tried it on a breadboard. You may get some significant popping because of the DC potential on those electrolytic capacitors, so you might need to add some resistors to reign this in.

User avatar
Nocentelli
Tube Twister
Posts: 2155
Joined: 09 Apr 2009, 08:06
Location: Leeds, UK
Has thanked: 839 times
Been thanked: 784 times

Post by Nocentelli »

tabbycat wrote:think the only question i still have is how do the balance and expander pots, switch (basic plastic slidey one) and footswitch (3pdt as i want an led to tell me when it's on) attach to the circuit board?
Pot wiring is done using numbered lugs: http://img.villagephotos.com/p/2004-11/ ... BERING.gif

...so "expander 2" on Mike vero layout means "connect this blue wire to lug 2 of the expander pot".

The switch (tone switch) has two outer lugs which are wired to the board (tone switch 1+2), and the middle is wired to the balance pot lug 1.

For the 3PDT footswitch bypass wiring, there are thousands of diagrams floating about on the net, I like this one because it shows all the vital connections:

http://gaussmarkov.net/images/1590B_SETUP_COMPLETE.bmp

The blue wire goes to the circuit input, and the yellow comes from the circuit output.
brownwhopping wrote:How can I learn by reading threads an making circuits, when some day I can see a lawsuit or somebody beat me in the face for that?

Rolbista
Solder Soldier
Posts: 178
Joined: 01 Feb 2011, 20:56
Completed builds: Mosrite Fuzzrite clone
Location: Poland, Gdynia
Has thanked: 4 times
Been thanked: 2 times

Post by Rolbista »

Hey guys, I'm in the process of building a Superfuzz and I'd like to know if its worthwhile to socket transistors in this build? I will be socketing the diodes but from what i've read in this thread, Superfuzz doesn't really care about specific trannies as long as they are medium-high gain silicons, right? I have 2n2222, 2n3904 and lots of BC108 (A, B and C).

User avatar
mictester
Old Solderhand
Posts: 2919
Joined: 11 Sep 2008, 21:29
my favorite amplifier

Mesa Boogie, Roost Sessionmaster, AC30

Completed builds

Hundreds! Mostly originals, a few clones and lots of modifications.

Location

Somewhat closer to Amsterdam than before!

Has thanked: 33 times
Been thanked: 749 times
Contact:

Post by mictester »

Rolbista wrote:Hey guys, I'm in the process of building a Superfuzz and I'd like to know if its worthwhile to socket transistors in this build? I will be socketing the diodes but from what i've read in this thread, Superfuzz doesn't really care about specific trannies as long as they are medium-high gain silicons, right? I have 2n2222, 2n3904 and lots of BC108 (A, B and C).

OK. Socket the transistors - you've got nothing to lose!

Remember - when these things were first built, the transistors available had fairly low gains (by modern standards). I would try the BC108A or B as the first try. You should get something quite close to the original. I built a couple of them using the CA3046 (using the pins 1 to 5 with the common emitters for the "long-tailed pair" part of the circuit. The results were pretty good.
"Why is it humming?" "Because it doesn't know the words!"

User avatar
Zombie_Crush
Breadboard Brother
Posts: 81
Joined: 26 Sep 2010, 03:05
Has thanked: 18 times
Been thanked: 1 time

Post by Zombie_Crush »

Hi all

I don't have any 2SC828 but do have a few 2N3904 at hand for this build - would i need to orientate the legs differently - I.e crossing the C collector to the B base position or would i just reverse the transistor for this build



thanks for your help :D

Ripdivot
Resistor Ronker
Posts: 318
Joined: 19 Jan 2008, 20:15
Location: Canada
Has thanked: 9 times
Been thanked: 68 times

Post by Ripdivot »

amp_surgeon wrote:
B3ar wrote:Is there an "octave off" switch mod worth doing?
Sure. You'll need a DPDT switch. One pole should break the connection between the wiper of the expander pot and the electrolytic on the base of the 3rd transistor (the phase splitter). The other pole should break the connection between the tied collectors of the 4th and 5th transistors (the differential amp) and the electrolytic just before the germanium clipping diodes.

Code: Select all

              "Expander" pot wiper <---*   *---> "-' side of electrolytic on base of 3rd transistor
                                        \
                                         \
                                          *-+
                                            |
                                       *----+
                                        \
                                         \
collectors 4th and 5th transistors <--*   *---> "+" side of electrolytic before Ge diodes
Sorry if this is a little difficult to make out. The asterisks are the switch lugs. The upper three are the first pole, and the lower three are the second pole.

From my own measurements, if you've got 500mV going into the pedal, and you've got the "Expander" turned all the way down, then you'll have about 250mV going into the base of the third transistor - the phase splitter, and almost 500mV at the collectors of the fourth and fifth transistors - the differential amp. If you turn the "Expander" up much at all then the diodes begin to conduct, and the signal will be clipped, so this is the only level where you get to see the real difference between the signal amplitudes. What does this mean? Well, it means the signal going into the clipping diodes will only be about half what it would normally be when the "Expander" pot is at minimum and the octave circuit is bypassed. You'll need to turn the "Expander" pot a bit more clockwise than normal before you'll start to get some clipping. There should still be plenty of headroom in the range of the "Expander" pot since the output of the second transistor is over 4V, and this is what will be going into the clipping diodes when the "Expander" pot is dimed. The max volume should be the same, since it's limited by the clipping diodes.

Caveat: I've never actually put this mod in a pedal. I've only tried it on a breadboard. You may get some significant popping because of the DC potential on those electrolytic capacitors, so you might need to add some resistors to reign this in.

The way I remove the upper octave is a little simpler. I just break the feed between the (-) side of the 10uf cap coming from the emitter of the phase splitter and the 470K resistor feeding the next stage. You can use a SPST switch but I have it on a DPDT stomp switch with an led so I know which mode I am in. Works great for me and the switch doesn't pop. The level between octave and no ovtave remains pretty close but of coarse you get more bottom end than the stock pedal because you are removing the out of phase signal. I find the pedal far more versatile with this mod. It even cleans up pretty good with the guitar volume knob.

bigmufffuzzwizz
Breadboard Brother
Posts: 132
Joined: 04 Mar 2011, 22:42
my favorite amplifier: 1973 Sunn Model T
Has thanked: 3 times
Been thanked: 2 times

Post by bigmufffuzzwizz »

What a great thread with some fantastic builds earlier on. I've built a few of the Leeds fuzz's and they are all awesome and over the top. The only thing I'd like changed is to replace the tone switch with a tone pot. I saw one build on pg. 5 that looked like they did it, but no info/values posted. I'll probably start with 100kb. I really wanna know how it sounds with the two tone options blended!!! :twisted:
Has anyone tried this successfully?
Magic Pedals Home of The Shrine Fuzz!

bigmufffuzzwizz
Breadboard Brother
Posts: 132
Joined: 04 Mar 2011, 22:42
my favorite amplifier: 1973 Sunn Model T
Has thanked: 3 times
Been thanked: 2 times

Post by bigmufffuzzwizz »

Zombie_Crush wrote:Hi all

I don't have any 2SC828 but do have a few 2N3904 at hand for this build - would i need to orientate the legs differently - I.e crossing the C collector to the B base position or would i just reverse the transistor for this build
poodlebra wrote: from reading through this thread i thought i just had to reverse my 2n3904s to substitute the 2sc828s, but now i've looked up the pinouts i see that:

2SC828: E C B
2N3904: E B C
Yes depending on which layout your using. Since Mike's layout used 2sc828's that would be correct.
Magic Pedals Home of The Shrine Fuzz!

Solidhex
Resistor Ronker
Posts: 262
Joined: 02 Apr 2008, 05:43
Has thanked: 10 times
Been thanked: 15 times

Post by Solidhex »

amp_surgeon wrote:
B3ar wrote:Is there an "octave off" switch mod worth doing?
Sure. You'll need a DPDT switch. One pole should break the connection between the wiper of the expander pot and the electrolytic on the base of the 3rd transistor (the phase splitter). The other pole should break the connection between the tied collectors of the 4th and 5th transistors (the differential amp) and the electrolytic just before the germanium clipping diodes.

Code: Select all

              "Expander" pot wiper <---*   *---> "-' side of electrolytic on base of 3rd transistor
                                        \
                                         \
                                          *-+
                                            |
                                       *----+
                                        \
                                         \
collectors 4th and 5th transistors <--*   *---> "+" side of electrolytic before Ge diodes
Sorry if this is a little difficult to make out. The asterisks are the switch lugs. The upper three are the first pole, and the lower three are the second pole.

From my own measurements, if you've got 500mV going into the pedal, and you've got the "Expander" turned all the way down, then you'll have about 250mV going into the base of the third transistor - the phase splitter, and almost 500mV at the collectors of the fourth and fifth transistors - the differential amp. If you turn the "Expander" up much at all then the diodes begin to conduct, and the signal will be clipped, so this is the only level where you get to see the real difference between the signal amplitudes. What does this mean? Well, it means the signal going into the clipping diodes will only be about half what it would normally be when the "Expander" pot is at minimum and the octave circuit is bypassed. You'll need to turn the "Expander" pot a bit more clockwise than normal before you'll start to get some clipping. There should still be plenty of headroom in the range of the "Expander" pot since the output of the second transistor is over 4V, and this is what will be going into the clipping diodes when the "Expander" pot is dimed. The max volume should be the same, since it's limited by the clipping diodes.

Caveat: I've never actually put this mod in a pedal. I've only tried it on a breadboard. You may get some significant popping because of the DC potential on those electrolytic capacitors, so you might need to add some resistors to reign this in.
If you break the connection between the expander pots wiper and the input of the phase splitter you've interrupted the signal path completely and the pedal won't work.

Ripdivot
Resistor Ronker
Posts: 318
Joined: 19 Jan 2008, 20:15
Location: Canada
Has thanked: 9 times
Been thanked: 68 times

Post by Ripdivot »

Today I took out the tone switch and installed a 50KB pot in its place and it worked really well. I was still able to get the 2 stock tone sounds and all points in between. There was a little volume loss the more I went to the center rotation of the pot but nothing major. I'll probably try a 25KB pot tomorrow and see how that works.

bigmufffuzzwizz
Breadboard Brother
Posts: 132
Joined: 04 Mar 2011, 22:42
my favorite amplifier: 1973 Sunn Model T
Has thanked: 3 times
Been thanked: 2 times

Post by bigmufffuzzwizz »

Ripdivot wrote:Today I took out the tone switch and installed a 50KB pot in its place and it worked really well. I was still able to get the 2 stock tone sounds and all points in between. There was a little volume loss the more I went to the center rotation of the pot but nothing major. I'll probably try a 25KB pot tomorrow and see how that works.
Thanks for info. I need to get mine back from my buddy and give this a go. Your description is exactly what I'm looking for, and I don't really mind a little volume loss. :D
Magic Pedals Home of The Shrine Fuzz!

User avatar
Zombie_Crush
Breadboard Brother
Posts: 81
Joined: 26 Sep 2010, 03:05
Has thanked: 18 times
Been thanked: 1 time

Post by Zombie_Crush »

Hey all


just completed my build but am having problems :(

basically am getting ground hum and a faint fuzz signal - also the tone switch does nothing when switched. Have checked board for bridges etc and all wiring seems to be correct. I used 2N3904 and bent the C to B to the ECB style connection points of the 2SC828 and wrapped the legs in heatshrink to prevent them touching. Must say, I found Mad Mikes layout confusing at time regards where the Expander 3 and Balance 3 grounds should go exactly, so on my build I soldered them to the boards GND - am also confused as to whether I should be using Log or linear pots? (I used LOG 50k) Finally the SPDT Tone Switch, should I wire so Balance 1 from the pot is at one end of the SPDT - and the Tone switch connection points from the board next to each other in the row?


Would be very grateful for your help :D

Spam99
Posts: 3
Joined: 29 Sep 2011, 12:47
Has thanked: 2 times

Post by Spam99 »

Hey guys,

Just like to start by saying I am a complete begginer to pedal building and am not so good at reading schematics.
Having said that I have managed to buil the board fot the pedal and wire most of the other bits up.

Im having problems with the tone switch though. I have it in my head like so :

1 2

3 4

5 6

So the Tone 1 and Tone 2 wires from the board go to 1 and 2, and then 3 goes to Balance 1 and thats where i hit a mind block and cant figure what else goes where :(
It probably a really simple thing but any help would be much appreciated.
Cheers

Post Reply