4 Transistor Maestro Fuzz build review

Started by jmusser, June 15, 2006, 06:18:53 PM

Previous topic - Next topic

jmusser

I had this circuit printed off from Fuzz Central back in late 2004, and that schematic seems to have dissapeared off that site. Fortunately, I finally found it here:   http://www.montagar.com/~patj/maefuzz.gif  It appears to be the same exact one. When I first put it together, the output was very low, and my amp had to be cranked to 10 to really get much out of it. I contacted our resident expert on biasing problems (Gez), and gave him my transistor voltages. He said that Q2 was saturated, and I'd have to raise the 470K and lower the .001 network to get the collector voltage up where it needed to be. At the time, it was .96V. While I'm at it, I'll mention that my choice of transistors, were all Mullard OC140s and the diode was a 1N60 I had scavenged somewhere. After quite a bit of experimentation, I ended up with 840K in place of the 470K (added a 100K and 270K in series), and lowered the .001 to a 680pf. Now, we're cooking with gas! I finally got the level up where it should be (Collector voltage is now up to 1.46V). When I had the low output level, I had good fuzz, but now that the level was up higher, the fuzz was more like an OD. Gez said that Q3 is where the fuzz comes from, and that I would probably have to raise the collector voltage on it, by raising the 330K that goes from the base to the collector. I eventually raised it's value up 100K to 430K, and the fuzz was somewhat better, but I'm still not getting any "Satisfaction" (pun intended). I thought maybe the 1N60 was too whimpy for the design, so I replaced it with a new 1N34A. That did the trick! The top 50K pot coming off the collector of Q2, seems to adjust the fuzz intensity. In one direction, the fuzz is about as raspy, as anything I've heard, yet smoothed enough, not to have the more splatty sound of something like the Buzz Box. The more you adjust it the other way, the more bassy it gets, and the fuzz diminishes to the point where it's more of a superimposed fuzz on top of the fundamental. The bottom 50k pot pot seems to be a smoothing control, and also boosts the signal up. If the fuzz is maxed to rasp, and the bottom 50K is lowered to almost off, you get some pretty weird ring mod madness. This is on the neck pick up of course. This tone, is quite a bit different than any of the Tone Benders, and Shin Ei. It has a more of a raspy "crow call" type thing going on with the fuzz, then the "wasp in a jar" tone of those. This tone is not the Satisfaction tone at all, at least with my set up. I get way more of that with the Germanium Tone Benders, Shin Ei, and Selmer Buzz Tone. This effect did not like my SS amp. The A & E strings went into some sort of tracking fits when you played hard, that reminded me of when you rake your finger over a phonograph needle, or twist a plug in the jack, and partially loose connection. Very Ugly! What is the name of theis circuit BTW? I've heard of FZ1, FZ1a, FZ1b, and FZ1s. The first 3 seem to be 3 transistor types, and I can't find a schematic that links this circuit with being a Maestro Super Fuzz, but I'm guessing that's what this is. i know all fuzzes strat sounding the same after awhile, but the full out fuzz tone of this one I feel is unique. Thanks again to Gez for helping me through this process.
Homer: "Mr. Burns, you're the richest man I know"            Mr. Burns: Yes Homer It's true... but I'd give it all up today, for a little more".

MartyMart

Looks great Jeff, the only one's I have are either 3 transistor or the "Super fuzz" 6 transistor version.
The later is reported to be just like the Univox Super fuzz and possibly a few others ( Shaftsbury ? )

On the list it goes then ......... :icon_redface:

MM
"Success is the ability to go from one failure to another with no loss of enthusiasm"
My Website www.martinlister.com

gaussmarkov

yes, thanks very much for this thorough report.  and for the schem.  :icon_cool:

--gm

Dan N

#3
That transistor part number matches up to a 2N3391A, a medium gain (hfe 250-500) silicon npn.

Is this the fuzz with the big wheel knobs on the sides? I have seen this schematic but don't know which model it's from.

Sounds like a fun build!

Edit- the diode part number matches a 1N457A, whatever that is...

jmusser

That's interesting about the transistor types. The other drawing just said they were "probably germanium", and once I found this drawing, I never researched the numbers, since they were around way before I ever got here. I'll have to see if I can sub some in there and see what they sound like. I would imagine that if they'll bias, that the effect would have to be a lot more wicked and harsh sounding.
Homer: "Mr. Burns, you're the richest man I know"            Mr. Burns: Yes Homer It's true... but I'd give it all up today, for a little more".

Sir H C

The FZ-1 and 1A are 3 transistor Germanium types.  The FZ-1B is silicon, off 9 volts and either a 3 transistor type (I have a schematic for this but never seen one) or the 4 transistor one with the squealch feature.  The squealch cuts off the output when the signal gets below a certain threshold.  The FZ-1S a 6 transistor one and uses transistors as the clipping diodes has two different sound settings and a lot more complex.  It too is all silicon.  A family shot:


Mark Hammer

I was given an original FZ-1S board but have yet to get it working.  I can confirm that the transistors are silicon type (2N3391 and 3392) but they come in a metal package.  Confusions about whether a given issue relies on Ge vs Si may well stem from quick glances that reveal transistors which look like they ought to be germanium.  As I've learned all too often, memory and quick glances can play some dirty tricks. :icon_rolleyes:

Interested readers can see the schematics here: http://hammer.ampage.org/files/Maestroworld.zip  The larger zipfile contains pdf's of different categories.  One of the pdf files is the entire FZ series.

Threads like this only serve to remind me of all those projects that are gathering dust and need to be returned to. :icon_redface:

Sir H C

Here are the guts of the FZ-1:



Yes, many silicon transistors came in metal cans back in the day.  IIRC it wasn't until the late 60s that they got the plastic packaging right, early on they would have moisture problems that would lead to early failures.

Mark Hammer

Thanks for the pic.  Dear lord, that is uuuuuuuuuugLEE!!  Thank goodness commercial pedals, and construction methods, have improved since then. 

You will note, as well, the presence of a single phone jack, and the shielded cable that leaves out the bottom of the image.  There is, of course, all sorts of room in there for a second jack.  A great many pedals in those days would come with a hardwired cable and phone plug.  It was understood that the patch cable to the amp was simply a part of the pedal.  Keep in mind that there were few other pedals to even consider owning at the time, and if the amp had tremolo and reverb, and you bought/built a fuzz, then what more did you REALLY need?  Consequently, the very idea of short patch cables, and dual phone jacks for using them, would have been a bit of a head-scratcher for many commercial manufacturers.

Sir H C

The funny thing is that the cable with the pedal goes to the guitar.  The FZ-1 didn't have any writing for what the 1/4" jack was, the 1A added the writing so that you knew that the jack was for the amplifier.  The first 1Bs also had the hardwired cord, then it switched to the two jacks.  Heathkit and Sekova who pretty much copied this pedal did the same thing with the hard wired cord.

MartyMart

Anyone know if the values off Q1's base and emitter are correct ?
They read as 33k and 82k, but have spaces ie: 3 3k  and 8 2k
So could they be 3k3 and 8k2 ??
All the 0.1uf caps are similar, with a space " 0 1uf" no "dot" .... hmmm

Thanks,
Marty.
"Success is the ability to go from one failure to another with no loss of enthusiasm"
My Website www.martinlister.com

MartyMart

#11
mp3 of it :
http://aronnelson.com/userfiles/Satisfactionfuzz.mp3

With 33k and an 8k2 !
Q 1 & Q 3 have 500k trimpots instead of the 470k's

Sounding great, but could be a bit louder, it's above bypass level though :D

MM.
"Success is the ability to go from one failure to another with no loss of enthusiasm"
My Website www.martinlister.com

gaussmarkov

this is a great thread.  thanks everyone! :icon_cool:

Mark Hammer

Quote from: Sir H C on June 16, 2006, 11:30:00 AM
The funny thing is that the cable with the pedal goes to the guitar.  The FZ-1 didn't have any writing for what the 1/4" jack was, the 1A added the writing so that you knew that the jack was for the amplifier.  The first 1Bs also had the hardwired cord, then it switched to the two jacks.  Heathkit and Sekova who pretty much copied this pedal did the same thing with the hard wired cord.
Gah!  You're correct.  I looked at the picture too quickly and mistook the transistor snuggled up to the jack as the tip contact and the other as the ring contact. :icon_redface: :icon_rolleyes:  Foolishly, I was wondering afterwards "Geez, why would they have what appears to be a power switch on the back of that pot, yet still use a stereo input jack to enable the battery?  Seems kinda redundant."  Because it IS, you dolt!! :icon_lol:

Marty,
That sounds pretty authentic is you ask me.

Sir H C

Mark, don't feel so bad, that was why I got that one cheap on the 'bay.  "Doesn't Work" (when plugged in backwards) :)

MartyMart

Quote from: Mark Hammer on June 16, 2006, 03:30:54 PM

Marty,
That sounds pretty authentic if you ask me.

Thanks, like a lot of these Fuzz circuits, the tolerances for transistors/bias can be way off, I've very rarely had them
come up sounding "right" with fixed value resistors, that can only be done with pot's, then measured and
replaced with the same value resistor.
90% of the time I'll use trimpots, be it 10/20/100k whatever, and that always gets a decent result.
If you use them at collector and either base/emitter, depending on the circuit, it's pretty much guaranteed
to work out.
Of course, it helps to find gain/leakage values first ! ( if they're Ge that is )
Worth spending that extra dollar on a couple of trimpots  :icon_wink:

MM
"Success is the ability to go from one failure to another with no loss of enthusiasm"
My Website www.martinlister.com

Dan N

Soooo. This is a 1b variant? What's the one with the big wheel knobs? Anyone have one to trace?!?

Sir H C

Big knobs is the just the Fuzz.  Also they made the Fuzztain.  Both are op-amp based circuits.  I have the schematics somewhere at home. 

jmusser

Hey Marty, yours sounds pretty close to mine. It has that nice rasp to it, and not quite as buzzy and high pitched as the various Tone Benders and Shin Ei. I really believe that the germaniums account for that tone, although, I haven't tried silicons in there yet. Is that pretty much your opinion too?
Homer: "Mr. Burns, you're the richest man I know"            Mr. Burns: Yes Homer It's true... but I'd give it all up today, for a little more".

MartyMart

Jeff, I found the Ge's to be thinner and more trebly sounding, for that sound clip I have 2N3114's
in Q1 and Q3 and 5088's in Q2 and Q4
I need to replace the 33k, which as I thought should be a 3k3 !!
The other r is an 8k2 indeed.
For the Ge's I should probably gain test a set and try them again ...

MM.
"Success is the ability to go from one failure to another with no loss of enthusiasm"
My Website www.martinlister.com