Input buffer for fuzzface type circuits - a good idea?

[brett]

Hi.  I just added an output buffer to my wah pedal (simple JFET type).  Without thinking, I added the buffer AFTER the bypass switch.  So now I had a fixed buffer between the guitar and everything after the wah.  

This included a Miss Piggy (fuzz face variant) and a Bazz fuss, both of which have very low input impedances, which reportedly is part of their mojo.   :oops:  Had I stuffed up the sound of these pedals?  I gave them a go with the buffer in place.

In my opinion, the sound of the pedals was significantly improved by the high-impedance (about 1M) buffer.  It seemed to have more clarity, more high-level harmonics, more sustain.  

My questions are:
Is there a reason why the low input impedance of fuzz-face type circuits should give a better effect?  
Has anybody else had a similar or contrary experience?

[petemoore]

Looks like you've found the 'difference'.
 I kinda like the TB or boostered or  BUFFed F.F.
 All A matter of tastes...

[Fret Wire]

In my opinion, the sound of the pedals was significantly improved by the high-impedance (about 1M) buffer.  It seemed to have more clarity, more high-level harmonics, more sustain.  

That was with the Wha bypassed?

[brett]

Yeah.  Because I put the buffer after the bypass, the buffer is now there all of the time (whether or not the wah is bypassed).  It's kinda interesting the effect it has on the Bazz Fuss. I wouldn't say that it's a lot better - just different.  But the Miss Piggy is a lot cleaner.  

I guess the input buffer is the main difference between a Tonebender and a Fuzzface, so it shouldn't have surprised me too much that it gives long, fuzzy sustain.

[Ge_Whiz]

When I try to use my Ge FF with a guitar with built-in buffer stage, I lose most of the control over the fuzz effect - it just sounds the same at all settings. Of course, most users wouldn't notice because they have their FF cranked up full all the time...

[petemoore]

Tends to make guitar rolloffs less effective, or different, 'till I get to around 2 on guitar vol., just sdoesn't seem to have the same 'cleanup' facility.

[Gus]

Take a good look at the 3 tran fuzz in schematics.  It uses a buffer and a 10 k between the buffer and FF section to give back some of the vol of the guitar fuzz control.


The FF works its best right after a passive guitar/bass the pickups and controls are part of the feedback network.  The input of a FF is a current summing point.  The FF has two gain stages the first transistor has its gain controlled by the feedback R 47k to 100k most of the time divided by the MESS infront of it in parallel with the openloop gain of the first transistor stage., the guitar/bass pickupups controls.  The pickups being passive have inductances etc so if you do the math you will find out thet is a high end rolloff caused by this.

If you made it this far you might want to add a inductor and some other stuff instead of the 10k resistor in the 3tran.  The 10k was used to add "touch" and some gain control.

The way the FF circuit works with the mess in front of it is a part of its sound.

[dosmun]

I ran a buffer in front of my Boutique FF last night and there was the sound I have been looking for.  I have built a buffer circuit and I am going to install it in my FF tonight.  I am making it switchable so I can turn the buffer off.

[petemoore]

and used a MPF102, 4.1k on the source, IM gate resistor, and 100ohm to 9v, 4.7 uf output cap, and .01uf input cap.
 It improved the definition and clarity of the sound in general, retaining [improving?] the Fuzz element,  losing the ability to use the guitar vol as gain rolloff...yupp yupp...
 Mine may have been suffering somewhat from having to go through the input gain, and input cap blend resistors and caps.
 It certainly seems to eliminate the question of enough input drive for the FF equation.
 I instantly took a liking to the improved sustain properties with my set up.
 It took the wooliness from the low end, has much better low end definition, In general seen as a good thing, though the wooly low end can be used to good effect...
 Stand alone it sounds great, I'm about to go try it with wah and boosters and phase

[petemoore]

In front of the Buffed Up FF, and played Aerosmith and many other related tones requiring this [to me] recognizable Q/Fuzz...
 Thinking...now, that's sounding really superb...
 It took some dialing on the MkII, the normal channel [only] putting out a very cool, almost wah like EQ....
 That would be a VOX Treble Booster setup, with a pretty small input cap by the sound of it, a clone with a Nice GE Hfe 148 IIRC...for those whom it may concern!!!

[Paul Perry (Frostwave)]

Take a good look at the 3 tran fuzz in schematics.  It uses a buffer and a 10 k between the buffer and FF section to give back some of the vol of the guitar fuzz control.

I think Gus is on the case here. I'd put a buffer after the guitar and then have a pot wired as a variable resistor going to the input of the fuzz, this gives you what appears to be a pickup that you can vary the impedance of. So you dont have the problemn taht a fuzz only sounds 'right' with particular pickups.

[dosmun]

I put a buffer in my Fuzz pedal and a switch to take it out of the circuit.  The buffer worked great but when I would bypass it the signal to the fuzz was weak.  I then inserted a 10K trimmer after the buffer before the Fuzz circuit and BAM problem solved.  I now have a TON more Treble when the bypass is engaged which is great for Humbuckers and the normal unbuffered sound which is better with single coils.

Thanks again for some more great tips guys.  I learn a lot more everyday.  And to think I wasn't a fuzz guy a couple months ago.  My FF just keeps evolving.  I think I am done tweaking this one, finally.  Any more tweaks I will save for a different Fuzz pedal.

[petemoore]

"I think I got it now", sometimago.
 I just modded my FF. AGainagin.
 I think I got it NOW.
 Always good to have 'another for comparison/reference. Compare the two different 'worlds', choose one, or commute. Live in one, while you 'remodel' the other...
 "The Buff Pig", "Buffy the Pigslayer", "Miss Buffy". "8 Pin Fuzz", "Pig Face"...[my personal favorite}, and "Pig Fuzz". "TM"