been a while, thought i'd drop something "new" on ya'll

[pinkjimiphoton]

i call it the stupor phuzz. it's ok, not fantastic, but it doesn't really suck, either. pretty bog-standard easy build and circuit based on standard dumb principles. feel free to @#$% with cap values etc, the clipper... the pre control you can go a bunch of different values. depends on what kinda gain ya want. same with the fuzz. 100k is fine, 500k, didn't try 1m. 250 seemed best. ya gotta easy 20% tolerance, and i tried to make it with bog-standard parts and values most folks are likely to have.
i am a huge fan of the 1458 chip. so that's what i use. marginally different tone with tl0X2, 5532, etc etc
socket everything.
the other thing with this was to try to keep the parts count pretty low. you can replace the pre control completely if ya want with just a resistor around 47k or so and get it down to two knobs.
just something to play with. if'n you're bored.
haven't drawn up the schematic yet, sorry. too lazy at the moment... but the "pcb" layout should be close enough to see what's what. we're talking bonehead simple... but decent sounding.
hope ya likes it. if ya do, builds one. if ya don't, well, cool, build something else
peas

[pinkjimiphoton]

schematic

[Gus]

https://www.diystompboxes.com/smfforum/index.php?topic=117167.20

The opamp fuzz is fun to work with.

[antonis]

You aways use the most recent "state of art" items, like 1458 op-amp, Jimi.. 

[amz-fx]

I built the first one of these around 1983 for my friend, Rex Long who died last month from a stroke. (RIP)

It had one of the great singing distortion tones when driving his Traynor YGL-3 amp.

Best regards, Jack

[pinkjimiphoton]

hahahah just shows to go ya, nothing's "new". 

it IS a fun little thing to mess with. you can use just about anything for values and it will still fire up.

1458's are my fav for sure,. not a big fan of fet based jellybeans with fuzz. these sound better to me. totally subjective, of course

this one was based on something in an old electronic mazagine i found, they called it the super fuzz so i changed it to stupor as i thought it fit better

peace

[amz-fx]

hahahah just shows to go ya, nothing's "new". 

it IS a fun little thing to mess with. you can use just about anything for values and it will still fire up.

1458's are my fav for sure,. not a big fan of fet based jellybeans with fuzz. these sound better to me. totally subjective, of course

this one was based on something in an old electronic mazagine i found, they called it the super fuzz so i changed it to stupor as i thought it fit better

peace

1458 chips are certainly good to experiment with. Try a 4558 chip in this design for a little more fidelity, especially if you crank up on the gain!

Best regards, Jack

[pinkjimiphoton]

fidelity, yes, but this way sounds stupid good. i really like this chip for some reason. the guv'nor used 'em in the solid state jcm800 series, too.
there's some magic in that particular jellybean. at least to my ear but yeah, 5532, tl0X2, 4558 all sound pretty similar.
when i finally get around to building it on vero, i'll stuff a socket in it. this is just messing with the breadboard to make a stupid simple circuit. tons of room for mods and tweaks, and i appreciate
you and gus posting other examples of similar circuits.
rock on, brother jack
peace to all

[Mark Hammer]

I've noted in older posts that a local guy brought his Timmy pedal over because he had read/heard that the 1458 was a sonic improvement over the stock dual op-amp in the Timmy.  I desoldered the original chip, installed a socket, and we auditioned about 8 different op-amps that evening.  I was skeptical at first, but curious nonetheless.  Much to my surprise, I liked the 1458 best, and so did he.  We found that its virtues lay in its weaknesses.  By having weak high-end response at higher gains, it functioned a bit like the "Presence" control in the King of Tone, which trims back on upper high end.  It smoothed out the tone of the circuit, and made it sound more relaxed to my ears, and less "tense".

That doesn't mean it would be preferable in all contexts.  It is a little hissier than more modern chips, engineered to provide better noise specs.  But it wouldn't be the first op-amp to yield a desirable high-gain tone due to its inherent inadequacies.

[amptramp]

There seems to be a big difference in input impedance between pinkjimi's schematic and amz-fx's schematic.  The time constant is the same but the first one would load the guitar tremendously.

Also, if you want to roll off the highs, just add a small capacitor from output to inverting input on both stages, done on the amz-fx schematic second stage but needed on both stages.  Even though you only need small amount of capacitance, it counteracts the capacitance to ground which is substantial with a "pre" control as in pinkjimi's schematic.  This may allow modern, quieter op amps to achieve the high-end rolloff that the 1458 achieves by its own incompetence at high frequencies.  Capacitance to ground at the inverting input increases the high frequency output by reducing the feedback at high frequencies.  The capacitor from output to inverting input counteracts that.

[Fancy Lime]

Apropos of nothing: is that really also the topology of the "EHX Opamp Muff Fuzz"? I have seen it referred to as that a few times but other than those schematics (not original EHX schematics), I have never heard anything about the Opamp Muff Fuzz existing or what box it came in. The Opamp Little Big Muff is something else. Does anyone know? Just curios.

More to the point: This topology really is great. Nice synthy compressed fuzz with 1N4001 clipping diodes. I built one many years ago with a big muff tone stack at the end, which imho is far from the worst "big muff sound" pedal you can build. And super easy, too. Damn it, now I'm itching to breadboard it...

Andy

[Mark Hammer]

I had one of the early 2-transistor Muff Fuzz units that plugged directly into the guitar.  The pair of 2N5133 transistors it came with may be in my parts drawers or built into another pedal of some type.  The enclosure has been adapted to have input and output jacks, and now houses an AMZ Mosfet booster.

One gig that our band played had two such plug-on-board units provided to me for the evening.  I plugged them in series such that they stuck way out from the guitar.  Not handy.

For some reason or other both EHX, Jordan, and Dan Armstrong thought they were doing players a favour by providing pedals that plugged right into the guitar.

[pinkjimiphoton]

brethren,
you know me....

10,000 monkeys with 10,000 typewriters and 10,000 years. a lot of the time, i'll just be dicking around with an idea in my head, and think of what the easiest way to achieve it is.
i LIKE the 1458. it sounds the most "marshally" to me usually.
a few months back, ever lazier in my decrepitude and decline, i decided to forgo the pedalboard for a gig, and return to my roots... a les paul, a cord, and a marshall.
my pref is for the marshall "52xx" series, solid state, based on the 1458's peculiar suckalities and built over the course of the mid 80's... 83-88-ish. why? cuz basically, they sound just like a GREAT germanium fuzzface into a cranked tube amp... without the noise and quirks of the fuzz... which i have used for years to make it sound like .... a les paul into a cranked up marshall.

when i was revisiting a  company i work with's designs i had revised one of them and chose the 1458 cuz they were looking for a marshall-esque kinda tone... plenty of distortion, relatively graceful clipping til it slams the rails, at which point it square waves BEAUTIFULLY like a pegged and exploding tube. i love it.

was later i discovered marshall was using them, too. so now my rig has degenerated to the purple quilt les paul semi hollow i built years ago, a shitty proco 30 foot cord, and (usually) a marshall 5212 i rebuilt and restored, 50 watts, two channel <sorta> reverb with fx loop and channel switching. i just leave the reverb on and the dirt channel fairly cranked, and turn my guitar up n down for everything else.

works just like a fuzzface and a strat for all intents. love, love, love.
but anyways, that's where my current infatuation with this relatively crappy cheap-ish (til people read this) chip.

if ya try one of that series marshalls, expect to replace every freeking electro on the board, including all the tants. ALL of them. replace the 15.1v zeners too. if its got channel switching, and bleed, expect to change out the 914's in the switching circuit. the one i use live is working perfectly, the one i keep by the bench is having issues i still need to sort out.

but the biggest improvement to them marshalls is to ditch the standard celestion g12m70's, and replace them with peavey scorpion 12's, 8 ohm. nite and day... the solid state loses the "graininess" the celestions give, particularly to long sustained notes, and them scorps <tho not rated higher khz> eliminate that graininess, add about 2 octaves more of high end sparkle and harmonics, like, you can latch onto a note, feed it back, and then catch different overtones as ya turn or move the guitar, or by finger vibrato. and they're pretty much un-blowable. can't say enough about them.

sorry to hijack...errr... my thread... but that's basically why i'm such a huge fan of this jellybean

[j_flanders]

The time constant is the same but the first one would load the guitar tremendously.

When I build from scratch this circuit is often what I start with. And then I add various tone controls, clipping options etc.
The 10k input impedance (I sometimes use a 100k pot in that spot) is perfect for excellent cleanup with the guitar's volume pot.
It works the same way a Fuzz Face cleans up. Guitar's volume pot rolled back increases Rin and reduces gain.

For some reason or other both EHX, Jordan, and Dan Armstrong thought they were doing players a favour by providing pedals that plugged right into the guitar.

And yet you post a picture of one that plugs into the amp.
But you're right, the first version was to be plugged straight into the guitar.
There's an old ad somewhere in which they announce the 'improved' version you posted.
I think there was also a version that came with a separate male/male jack so you could choose to plug it into either the guitar or the amp.
Edit: found it:

[Mark Hammer]

Too funny.  I was so familiar with the version that plugged into the guitar I didn't even bother to read the legending in the pic.  Okay, here's the version I used.  You will note that the LPB-1 has the plug on the output side, but the Muff Fuzz has it on the input.  Weird.  The innards were ugly; a spider web of flying leads.

[iainpunk]

Apropos of nothing: is that really also the topology of the "EHX Opamp Muff Fuzz"? I have seen it referred to as that a few times but other than those schematics (not original EHX schematics), I have never heard anything about the Opamp Muff Fuzz existing or what box it came in. The Opamp Little Big Muff is something else. Does anyone know? Just curios.

More to the point: This topology really is great. Nice synthy compressed fuzz with 1N4001 clipping diodes. I built one many years ago with a big muff tone stack at the end, which imho is far from the worst "big muff sound" pedal you can build. And super easy, too. Damn it, now I'm itching to breadboard it...

Andy

i know the schematic you refer to, and i believe that 2 opamp schematic is the muff fuzz, the opamp big muff has 3 opamps

[j_flanders]

Apropos of nothing: is that really also the topology of the "EHX Opamp Muff Fuzz"? I have seen it referred to as that a few times but other than those schematics (not original EHX schematics), I have never heard anything about the Opamp Muff Fuzz existing or what box it came in.
Andy

https://www.diystompboxes.com/smfforum/index.php?topic=117223.msg1088416#msg1088416
https://www.diystompboxes.com/smfforum/index.php?topic=117223.msg1088254#msg1088254 (I'll try and fix the broken links later on)
Edit: It seems I can no longer modify my post in that old thread. I was able to retrieve the photo's from all those broken links though, but I don't know if this is the right place to post them.

[thetragichero]

I'm silly with 1458s salvaged from old organs

[amz-fx]

I based my design mainly on an old design in a NatSemi book, and influenced by the Craig Anderton fuzz in EPFM.

The Muff Fuzz differs radically in that there is no feedback resistor on the second op amp, so it runs full blast all the time, limited only by the diodes. This makes for a more distorted sound but not much flexibility.

The old schematic of the Muff Fuzz below probably has a couple of errors in it. The diodes were reportedly 1N34a germaniums.



Best regards, Jack

[j_flanders]

The Muff Fuzz differs radically in that there is no feedback resistor on the second op amp, so it runs full blast all the time, limited only by the diodes. This makes for a more distorted sound but not much flexibility.

On the (incorrect?) schematics there's no feedback resistor on the second amp but in the actual pedals there was a 470k resistor.