Why won't my MXR Classic 108 Fuzz play fair?

[jamie.pope]

I was really chuffed when i first purchased the MXR 108 in October; both in terms of value for money and also for providing a Fuzz Face in a pedalboard friendly enclosure. However, i have begun to encounter numerous issues with it in terms of 1.) it's sound 2.) it's placement in my chain and 3.) how it reacts to my Ernie Ball Jnr vol. pedal.

I should mention that i've recently begun using a Gibson SG and overdrive my DRRI with the Super Duper (side one) at all times.

I'm running as follows:

Boss TU-2 - Ernie Ball VP Jnr - MXR 108 - Zvex Super-Duper - Strymon Brigadier - EHX Cathedral - Fender DRRI.

Even with the 108 dimed, i cannot get enough output from it, it simply produces a static fizz that if anything, is of neutral volume to my clean sound. What's worse, is that it becomes increasingly temperamental concerning my TU-2 and volume pedal's placement. The sole reason i have the volume pedal placed before the 108 is because adjusting the volume on the SG isn't nearly as practical as on a Tele. However, placing it where i currently have it produces even worse results from the 108 - spitty, mushy, flat; zero definition.

Are there some rules to using fuzz pedals that i need schooling on? Is running overdriven humbuckers into it a cardinal mistake? Do they react better to a clean sound?

Any help would be greatly appreciated as it's beginning to really annoy me and ofcourse, if anybody has had a similar experience, please chime in.

Jamie

 

[p8t8r]

Try it first in the chain, even before tuner. Guitar -> MXR108 -> Tuner -> Etc...

 

[11 Gauge]

Many older fuzz designs have a very low input impedance. If you smack the front end with a buffer, it will screw up the sound, and destroy the quality of being able to clean up the fuzz tone with your guitar's volume control.

Since the 108 is a Fuzz Face basically, it needs to be placed with no buffers in front of it. This may not be practical with many pedalboard setups, but it is just one of those facts that typically can't be skirted around. Some folks do manage to find ways to make something buffered in front work, but IMO it just destroys the best natural capabilities of the FF, and is really why it would be chosen over something else.

Your Super Duper is always on? That will degrade the sound as well. You are basically chaining a third (and fourth if using both) transistor to the Fuzz Face circuit. The SD uses totally different transistors called mosFET's that have a very high input impedance and a WHOPPING amount of gain (compared to what is used in a fuzz pedal), so they will dismantle the sound on the 108's output.

...The Fuzz Face is VERY crude - the output actually is a sort of tone filter. But it is the crudeness at the output (just like at the input) that makes it great at what it is. So having anything on after it will almost always screw things up.

Getting a FF up to unity gain is not an uncommon issue. Turn the level all the way up if you need to. Of course, if you remove anything in the signal path after the FF, this may become a moot point.

There are tweaks to get the volume higher sooner on the level dial, but you should try to avoid them if possible. They basically consist of replacing the 330 ohm resistor with 680 ohms or bigger (some use up to 1.2K), and then replacing the 8.2K resistor with a 10K trimpot. The trimmer is needed to adjust the voltage at the second transistor's "collector" lead to around 4.5VDC (an easy operation if you need explanation). But again - I'd try to avoid this.

I know the 108 has the buffer switch, but I like to think of it as a "flexibility gesture" that may not have any practicality.

But general rule of thumb with an old fuzz design is no buffers in front of it, and nothing engaged after it that would screw up its operation. So your TU-2 and Ernie Ball pedals can't be in front. And - the Super Duper should be off. Anything that is buffered bypass after the fuzz is fine - stuff like Boss or Ibanez pedals, Dano pedals, obviously many mass produced delays and stuff like that.

I just always set up my boards to have anything with a buffer after anything like a FF. So my Boss pedals are usually near the end, right before my trems/delays/etc.

If you are ever questioning whether or not other pedals are affecting your fuzz's sound, A/B it by itself and then in the chain with your other pedals. Some pedals that are marketed as being true bypass are not, and they can mess up the sound of a FF/108/etc. if placed in front, too. Otherwise, a true bypass pedal in front of a fuzz is not an issue (as long as it is off!).

Good luck!

 

[jamie.pope]

Many thanks for your replies guys, particularly you 11 Gauge. You've pretty much answered all of my questions and taught me plenty in the process... however, your insight has prompted further probing!

Getting the 108 up to unity has never been a problem; as i said, even with the output dimed, i'm at unity. All i truly require from the pedal is more output. Ofcourse, the aforementioned points have answered some of my former questions/problems; however yesterday i did in fact try the fuzz face first in the chain and the same problems persisted. Could it be that i'm asking too much from the fuzz face? Do i simply want more output than it's capable of delivering?

Should the case be that a fuzz face isn't for me; in terms of output, what should i be looking out for? Will i encounter such issues with other manufacturers or are such issues exclusive to the fuzz face design?

Many, many thanks again. This is truly helpful insight.

 

[Cameage]

.011, should I not have my tuner before my Muff clones, or is the Muff a different enough type of circuit for buffers not to matter with it? I'd consider the Muff a "vintage" circuit, but for all I know, it's a different animal.

To be clear, I mostly use a Pumpkin Pi, which is a clone of the op-amp Big Muff, if that changes anything.

 

[11 Gauge]

Many thanks for your replies guys, particularly you 11 Gauge. You've pretty much answered all of my questions and taught me plenty in the process... however, your insight has prompted further probing!

Getting the 108 up to unity has never been a problem; as i said, even with the output dimed, i'm at unity. All i truly require from the pedal is more output. Ofcourse, the aforementioned points have answered some of my former questions/problems; however yesterday i did in fact try the fuzz face first in the chain and the same problems persisted. Could it be that i'm asking too much from the fuzz face? Do i simply want more output than it's capable of delivering?

Should the case be that a fuzz face isn't for me; in terms of output, what should i be looking out for? Will i encounter such issues with other manufacturers or are such issues exclusive to the fuzz face design?

Many, many thanks again. This is truly helpful insight.

So by more output you mean more fuzz/saturation/etc.? Not more volume out?

There is a point with a FF where it just primarily saturates to a certain point, and you can't go above that no matter what you do with the knobs. So it may be that "phenomenon" that you are alluding to.

I'm just not sure whether or not we are talking apples and oranges here, so to speak.

It kind of sounds like you almost want more distortion, or some kind of tighter/more saturated sound when you say output?

And if the pedal is first in line and "the problem persists," AND you also tried it with JUST the 108 and no other pedals in the chain and it still persists, then I would be inclined to say that you either need a different kind of fuzz, or a different kind of dirt/drive box (maybe more of a distortion).

 

[11 Gauge]

.011, should I not have my tuner before my Muff clones, or is the Muff a different enough type of circuit for buffers not to matter with it? I'd consider the Muff a "vintage" circuit, but for all I know, it's a different animal.

To be clear, I mostly use a Pumpkin Pi, which is a clone of the op-amp Big Muff, if that changes anything.

Thanks for clarifying, because op amps generally have a much higher input impedance as an inherent part of their design.

The older transistor based Muffs do indeed have very low input impedances too, but there is typically a 33K+ input resistor which partially offsets the effect. Also, the clipping diode arrangement in ALL Muffs basically throws the low Z input thing out the window, hence a Muff just will not clean up with your volume knob like a Fuzz Face will. The clipping diodes "limit and bound" what your signal does at each gain stage that has them. With the FF, the clipping is asymmetrically created completely by the pair of transistors themselves.

...Even if you removed the clipping diodes in a Muff, they are still individually "bound" by their own feedback loops (less so by the 4th transistor, but it is really only used for signal recovery after the tone control).

But - try it for yourself (although you prob. won't hear anything with your IC Muff). If you put a buffered bypass pedal in front of a transistor Muff, it usually will get a little brighter, because any "loading" from the first transistor is effectively removed by the buffer in front.

...In essence, this is EXACTLY how the Boss DS-1 is set up: input buffer into a transistor stage that is almost exactly the same as that of a Muff. But because of the buffer, the input impedance effectively matches something like a Tube Screamer.

I used to have a bunch of the Ibanez Sound Tank "60's Fuzz" pedals, and they were actually Muff clones with the old TS/Boss buffered bypass. In spite of whatever tweaks I did to them, I could not get one to sound as good as my old "version 2" ram's head.

You might want to check out some YouTube videos of the Lovetone Big Cheese. It basically "wraps" op amp buffers around a tweaked Fuzz Face, and it just creates this splatty noise of a mess. I know the BC has a sort of grail status now, but the buffers IMO just wreck what the pedal could really do, unless someone literally wants the sound of solid state meltdown.

 

[Chiogtr4x]

Many older fuzz designs have a very low input impedance. If you smack the front end with a buffer, it will screw up the sound, and destroy the quality of being able to clean up the fuzz tone with your guitar's volume control.

Since the 108 is a Fuzz Face basically, it needs to be placed with no buffers in front of it. This may not be practical with many pedalboard setups, but it is just one of those facts that typically can't be skirted around. Some folks do manage to find ways to make something buffered in front work, but IMO it just destroys the best natural capabilities of the FF, and is really why it would be chosen over something else.

Your Super Duper is always on? That will degrade the sound as well. You are basically chaining a third (and fourth if using both) transistor to the Fuzz Face circuit. The SD uses totally different transistors called mosFET's that have a very high input impedance and a WHOPPING amount of gain (compared to what is used in a fuzz pedal), so they will dismantle the sound on the 108's output.

...The Fuzz Face is VERY crude - the output actually is a sort of tone filter. But it is the crudeness at the output (just like at the input) that makes it great at what it is. So having anything on after it will almost always screw things up.

Getting a FF up to unity gain is not an uncommon issue. Turn the level all the way up if you need to. Of course, if you remove anything in the signal path after the FF, this may become a moot point.

There are tweaks to get the volume higher sooner on the level dial, but you should try to avoid them if possible. They basically consist of replacing the 330 ohm resistor with 680 ohms or bigger (some use up to 1.2K), and then replacing the 8.2K resistor with a 10K trimpot. The trimmer is needed to adjust the voltage at the second transistor's "collector" lead to around 4.5VDC (an easy operation if you need explanation). But again - I'd try to avoid this.

I know the 108 has the buffer switch, but I like to think of it as a "flexibility gesture" that may not have any practicality.

But general rule of thumb with an old fuzz design is no buffers in front of it, and nothing engaged after it that would screw up its operation. So your TU-2 and Ernie Ball pedals can't be in front. And - the Super Duper should be off. Anything that is buffered bypass after the fuzz is fine - stuff like Boss or Ibanez pedals, Dano pedals, obviously many mass produced delays and stuff like that.

I just always set up my boards to have anything with a buffer after anything like a FF. So my Boss pedals are usually near the end, right before my trems/delays/etc.

If you are ever questioning whether or not other pedals are affecting your fuzz's sound, A/B it by itself and then in the chain with your other pedals. Some pedals that are marketed as being true bypass are not, and they can mess up the sound of a FF/108/etc. if placed in front, too. Otherwise, a true bypass pedal in front of a fuzz is not an issue (as long as it is off!).

Good luck!

Hey .011 (again!)

With an FF Type, I understand that the FF should be the first in line (no problem there, if I ever get one, I'd just run it on battery, off the board, first), BUT is it a bad idea to engage any kind of OD (BD-2, Timmy Type) later on in the signal chain- or best to leave all the "dirt-making" to the FF? thanks

 

[11 Gauge]

Hey .011 (again!)

With an FF Type, I understand that the FF should be the first in line (no problem there, if I ever get one, I'd just run it on battery, off the board, first), BUT is it a bad idea to engage any kind of OD (BD-2, Timmy Type) later on in the signal chain- or best to leave all the "dirt-making" to the FF? thanks

There are no hard and fast rules - whatever sounds acceptable is all that matters.

To date, I have not found any type of drive box to run after a FF that sounded beneficial, but I think I'm trying to "stay within the lines" when it comes to using that particular pedal.

To demonstrate that there are no hard and fast rules, I can briefly paraphrase what someone found when they removed the epoxy covering their Durham Crazy Horse. From what I recall, it is something akin to a TS-like stage (4558 op amp with soft clipping and a drive control), driven into a silicon FF with adjustable fuzz control, driven into ANOTHER silicon FF with a "fixed" fuzz level, into a Muff-type tone control. There's also what is basically just an op amp buffer stage in between the TS-like stage and the first FF (it uses a 4558, so it makes sense to employ both of the op amp stages).

...So the CH is like 3.25 pedals in one box! And TBH, I think it would be more of a fun, over-the-top noisemaker than the Vex Fuzz Factory simply based on the design differences. Out of the "three Fuzzfacezillas," I would pick the CH over the Big Cheese or Fuzz Factory. The only other "encaspulated hardwired crazy stacker" that I can think of that I'd also like to own is the Bixonic Expandora, which basically drives one Rat into another, and employs an optic device that varies the gain depending on the signal it "sees."

And some folks argue all the time about the merits of putting a compressor after a drive box, despite the generally accepted notion that it shouldn't be done. I seem to recall someone arguing that Gilmour might have done that on some lead work on some PF songs, but there was no way to prove it.

I really like the combo of something like a TS into a Red Llama, since the latter is good at being smacked with a hot clipped signal (if you like hyped up gain tones). And something like that is actually sort of what the foundation for the Mad Professor Stone Gray Distortion is, but again it's all hardwired and put in a single box.

 

[Cameage]

I was wondering how the Crazy Horse got that ridiculous fuzz sound. I definitely agree that, out of those three pedals, I'd want the Crazy Horse...but I don't have $250.

 

[ruger9]

Yeah... just so I fully understand... I can put ANY true-bypass pedal in front of a fuzz, and be fine (so long as I'm not using that pedal WITH the fuzz?) For example.. a TRUE-BYPASS wah before a fuzz would be fine... until you wanted to use them both, in which case the wah would need something like the foxrox buffer. Also, a TB tuner first in line, would also be fine before a fuzz right? (assuming the tuner mutes the output when on).

 

[puremania]

Depends on the fuzz, but yeah, that's the rule I follow; if it has a buffer, fuzz goes before it. And really, try the wah into fuzz, then reverse, see which works better, I've had some fuzzes that did beautifully before wah, but stank it up after AND vice versa.

And, yes, I know the all-fuzz-before-all-buffers is probably overkill, but it's worked so far

 

[11 Gauge]

Yeah... just so I fully understand... I can put ANY true-bypass pedal in front of a fuzz, and be fine (so long as I'm not using that pedal WITH the fuzz?) For example.. a TRUE-BYPASS wah before a fuzz would be fine... until you wanted to use them both, in which case the wah would need something like the foxrox buffer. Also, a TB tuner first in line, would also be fine before a fuzz right? (assuming the tuner mutes the output when on).

Yeah - any TBP in front is fine. That includes the new pedals that have the "milennium" bypass, which is effectively the same thing. I have a Biyang Compress X (w/mil bypass) as pedal #1 on one of my boards, and a pair of fuzzes after it, with no problems.

 

[Chiogtr4x]

^^ Thanks for the info Keith as usual- will try to store to aging or absent brain cells!

To be honest I know it's not the same thing but If I just stay with what I have on the board (when I want to use more than one OD or dirt for a gig, which for the moment is actually rare) I'm finding that the GFS "Rat" in "comp" mode with the Gain and Tone at 3:00 does not sound too far from a "FF" kind of sound (it's got rasp, sustain, but still low end), and that pedal does not seem to care if it is place before or after lower Gain OD's. I should just be happy with that- fine for my real life gig situations(small!)not perfect, but simple/manageable

 

[Telebrand]

I don't use a fuzz or even own one, but from what I have read/heard fuzz pedals HATE buffers! Even what you place after the fuzz messes with it! I have heard the differences and it is crazy that a pedal you put after the fuzz can affect its tone! You kind of have to just try em out till you find one that works.

 

[Chiogtr4x]

^^^ Maybe best to go "old school" Guitar >fuzz> amp! It worked for a lot of folks

 

[11 Gauge]

^^^ Maybe best to go "old school" Guitar >fuzz> amp! It worked for a lot of folks

It's HARD.

I ain't no Eric Johnson (not even close), but the "hybrid tone" that I've always wanted/needed in a FF is in large part what is to be found in the EJ sig FF model.

Granted, I tweaked the crap out of my own design that has elements of the EJ FF, but the point I'm making is that I use it in a similar manner as EJ does - almost always some delay going on, and it really does stuff for lead work and chords that I can't get with other fuzzes. You have some of that gnarly stuff on the lower strings, but a sort of fluid and sustaining quality to the higher strings (and notes).

...Those kind of fuzz tones just make for a more modern recipe, with delay and such, and oftentimes working the volume to get more of an OD tone. While EJ will sometimes conjure a Jimi vibe, it is only part of it.

I also use fuzz to get some Gilmour tones (older ones), and he used an Echorec and other gear (he was always a multi-gear guy), so again the Old School thing doesn't 100% apply.

But like I mentioned - I don't "go outside the lines" very much. I just use it with other effects, with a clean amp, but not (primarily) to conjure the old psychedelia thing (although I did have to give the early Zep a go after watching the videos for Retro Channel's The Fuzz).

That said, it can be done, but it's like the folks who just play a little tweed amp and work the volume knob. Or dime an AC30 and do the same thing.

The big problem with fuzzes and excessive volume is that you can typically end up just "riding the sustain," and that just won't fly in most circumstances these days. It is FUN, as long as the club is empty!

 

[beexter]

If you want a fuzz with more volume, I'd suggest looking at a Monsterpiece NPN (search the Harmony Central forums for Monsterpiece and you'll find out more). I have an MXR 108 and a Monsterpiece NPN - f or my set up (using either a tele or strat), with the fuzz control set to about 95% (just before you get that little boost at the end of the dial), the MXR volume is around 1 o'clock to be around unity, the Monsterpiece is around 9o'clock on the volume to get unity - it is a lot louder! The monsterpiece also has a bias control (like the Sun dial on an analogman sunface) so can get a variety of sounds from splatty to smooth. I'd highly recommend it.

 

[11 Gauge]

If you want a fuzz with more volume...

This is a common issue.

There are two straightforward ways to go if you can have someone do a little work to your pedal:

- replace the level/output pot with either a linear taper if it has a log taper or a REVERSE linear taper if it has a linear taper

...each "step up" in taper will give you more volume early on...

- enlarge the series resistor in the power rail to the second/last transistor (if not a FF), and adjust the bias trimpot/top pot size if need be

...the pair of two resistors provide a point where the signal is "tapped" that is the equivalent to "a pre-level level" that is fixed - it is not uncommon to increase a stock resistor that is 220 or 330 ohms up to 680 ohms, or even upwards of 1.2K

Some builders just do a massive "volume boost hack" - they only have a single resistor/bias pot, which gives the MAX volume increase. It makes life easy for them, and users find themselves setting unity at around 9:00!

That said, the fuzz circuit is such a primitive thing that you will typically just "top out" at some point, with any further increase to the level pot not doing much, because the final transistor is completely saturated, or you get those really nasty treble spikes as the transistor moves in and out of cutoff.

I REALLY don't like (topside) bias controls that don't stay within a nice range. When you go below a certain point, it just farts out. IMO, that's just noise. It's fine on something like a Fuzz Factory, but otherwise no thanks. And - when you go above a certain point, you are only adding volume/hiss/noise, and really reducing much of the fuzz to a negligible point. IMO, the most harmonically rich and chewy fuzz tones happen at sweet spots that aren't some textbook value of 4.5 to 5.1VDC. Sometimes you can go as low as about 3.1VDC and get oodles of harmonics/octave overtones, and a much less spikey sound, although the "sweet spot" is usually a little higher. It will also dictate to some degree how well (and fast) the fuzz cleans up with your volume knob.

 

[beexter]

I REALLY don't like (topside) bias controls that don't stay within a nice range. When you go below a certain point, it just farts out. IMO, that's just noise.

The Monsterpiece does stay within a nice range. When set to minimum, it doesn't get all starved and splatty and pretty well anywhere on the dial is usable. The amount of volume on tap makes it a very flexible pedal that can also work as a boost. I think it is also very reasonably priced for a made-to- order pedal.