Fuzz Face Authenticity

FractalAudio said:
Precisely. The Fuzz in the Axe-Fx reacts as though there is a buffer in front of it (because there is). It's a limitation inherent to all modeling products. I modeled it using a nominal source resistance. I forget what I used for the source resistance but it was probably around 100K ohms. As you said to really simulate it you would need a controller to simulate the changing output impedance of the guitar.
Click to expand...

Cliff, would a Radial Tonebone Dragster simulate this?
 
boogieman75 said:
Cliff, would a Radial Tonebone Dragster simulate this?
Click to expand...

I think you're getting it backwards. Although the FF probably has a direct effect on the pickups, the main issue is the other way around - the volume setting on the the guitar, with whatever side effects that causes, directly affects the FF circuit.

The Dragster looks like it impacts the pickups, by changing the impedance that they see on the output, which seems to me to be equivalent to the built in Axe input impedance parameter.
 
I think Stickman is spot on.

There is an A/D converter between the guitar pickups and the virtual Fuzz Face Drive Block. The guitar electronics are not part of the virtual Fuzz Face circuit.
 
Talking about fuzz:

One of my bands is going to play Bright Lights by Gary Clark Jr.
Lots of fuzz in that song.

I use the Face Fuzz model, with Drive around 3, for the rhythm part.

For the lead part I engage a second (stacked) Drive block, also Face Fuzz, with the Bias cranked.
That results in great spitting lead fuzz tone.
 
I have just had a short dialogue with Cliff about the fuzz face and impedance (via support) just to check if the auto impedance switching is working. He assures me that it is functioning correctly and the FF impedance (vs. resistance) and frequency behaviour has been modelled as best it can be. The buffered FF emulation is very accurate I think, but not ideal if you have a passive guitar and are a FF nut I guess (not that I am really, but I had a specific reason to try and emulate it).

I have found however (using my own recordings of my old '66 FF as a reference) that if the Axe input impedance (in the gate block) is switched down to 22k +cap the fuzz face simulation reacts to the guitar volume control in a very much more similar manner to the hardware- Try it! I think you will agree. When the volume is rolled back it cleans up and brightens up nicely. It might not be electronically correct, but in practice it works well.
As a result I have put a wish on the FX8 forum for the input impedance setting to be linked to a modifier so it could be changed by a CC or scene controller- Then it would be selectable to taste...
Adjusting the resistance loading on a passive guitar is also a good way to tame a shrill single coil pickup too for example of another use.
 
yek said:
Talking about fuzz:

One of my bands is going to play Bright Lights by Gary Clark Jr.
Lots of fuzz in that song.

I use the Face Fuzz model, with Drive around 3, for the rhythm part.

For the lead part I engage a second (stacked) Drive block, also Face Fuzz, with the Bias cranked.
That results in great spitting lead fuzz tone.
Click to expand...

Would you mind sharing your preset? I've always liked the way Gary Clark Jr and Jack White can get nasty gritty Fuzz tones. I don't understand how fuzz pedals are made, so I'm not too sure what parameters to tweak in the Drive Block.

I have a vintage Axe-Fx II Mark I, so you'd have to follow this process to share it: http://forum.fractalaudio.com/threa...-xl-and-xl-presets-with-mark-i-and-ii.109963/
 
I would think for the simulated interaction between the Fuzz and guitar to be completely accurate, the fuzz would have to know the loading characteristics of the pickup like its resonant peaks and such. There's no way to relay that information. We would need settings in the input block much like the speaker tab settings in the amp block or maybe a list of preset settings for common pickup types. Even this would be limited in that it would not reflect real time changes like rolling off the guitar volume or tone knobs. It's sort of like how the amp block and cab block are not directly interacting. You have to set the speaker tab settings to let the amp block know what kind of load it should simulate.
 
Lionheart said:
Same sentiments as others in this thread. The fuzz models need work done on them by FAS. Until then, I'll hang on to my fuzz pedal.
Click to expand...

I really love the Bender model in the Axe, which I would assume is based on an old Tone Bender...

But it would be awesome to have something more in the Burns Buzz teritory, and I know a lot of guys (myself included) would go ape shit over something that nails the Gilmour fuzz a little easier (P19, Erafuzz, or just maybe an altered version of the Muff?)
 
Rotti said:
I really love the Bender model in the Axe, which I would assume is based on an old Tone Bender...

But it would be awesome to have something more in the Burns Buzz teritory, and I know a lot of guys (myself included) would go ape shit over something that nails the Gilmour fuzz a little easier (P19, Erafuzz, or just maybe an altered version of the Muff?)
Click to expand...

Interestingly enough, a lot of the best Gilmour tones are actually coming from set-ups that aren't using any Gilmour associated models; no HiWatt, no Muff etc. Check out Bobby's Brit Floyd patches for example...spot on nails the tone, but isn't using the classic "formula".

Same with the dude that is touring with Roger Waters, he's using a Suhr Riot as a drive pedal, even though he surely could have access to any rare old pedals he wants, given the budget of that tour.

I think sometimes people get caught up in using the "proper" model, and then can't get the sound they are after, and instead of just using a different model, they stick with that isn't working sonically, because its historically correct.

Download any Brit Floyd show clip on Youtube and its clean the Axe can nail those tones sonically. It might not have the proper labeled models, but the tone is there
 
Jezza said:
I have just had a short dialogue with Cliff about the fuzz face and impedance (via support) just to check if the auto impedance switching is working. He assures me that it is functioning correctly and the FF impedance (vs. resistance) and frequency behaviour has been modelled as best it can be. The buffered FF emulation is very accurate I think, but not ideal if you have a passive guitar and are a FF nut I guess (not that I am really, but I had a specific reason to try and emulate it).

I have found however (using my own recordings of my old '66 FF as a reference) that if the Axe input impedance (in the gate block) is switched down to 22k +cap the fuzz face simulation reacts to the guitar volume control in a very much more similar manner to the hardware- Try it! I think you will agree. When the volume is rolled back it cleans up and brightens up nicely. It might not be electronically correct, but in practice it works well.
As a result I have put a wish on the FX8 forum for the input impedance setting to be linked to a modifier so it could be changed by a CC or scene controller- Then it would be selectable to taste...
Adjusting the resistance loading on a passive guitar is also a good way to tame a shrill single coil pickup too for example of another use.
Click to expand...

Great tip, thanks!
-
Austin
 
Well, I'm no electronics expert at all but, I think this whole analog/digital-I/O interaction can be solved.
I mean, you could even try measuting the guitar load characteristics with a RLC bridge, and include that information real time into the input of the pedal. But that wouldn't solve the problem of how to plug multiple pedals in series. Also, it would need new hardware, and it would introduce some serious latency when moving the pots.

Maybe if you consider both the guitar's circuit and the pedal's input circuit as LTI systems, you could extract the filter characteristics of both, and maybe try a convolution or something? This would mean you would have to take realtime IR's out from the guitar's signal though.
It's most likely all wrong, but I assume someone out there is trying to solve this, maybe even Cliff himself.
 
Any idea what is the clipping type trying to replicate when it's set to "variable" at default? Is it working more like a germanium or silicon fuzz? Finally I decided to try changing the impedance manually and actually got the fuzz face to clean up really well. Gonna try and change the clip type to silicon today and see what happens.

I've never owned a "real" Fuzz Face but I've been gasing for a Dunlop Jimi Hendrix fuzz face, which comes with a silicon transistor. This is mainly because I saw Gary Clark Jr using the same pedal. I loved the sound and it pairs with octavia really nicely.
 
aens said:
I've never owned a "real" Fuzz Face but I've been gasing for a Dunlop Jimi Hendrix fuzz face, which comes with a silicon transistor. This is mainly because I saw Gary Clark Jr using the same pedal. I loved the sound and it pairs with octavia really nicely.
Click to expand...

IMHO, a silicon Fuzz Face is a very pale imitation of the originals with germanium transistors. Germanium transistors are horrific components for digital or HIFI applications; they leak, they have no consistency between different units, they have low gain and they change characteristics with the temperature. But there's something magic in them for Fuzz Faces. All those crappy characteristics mellow out the distortion and the result is super cool.

Silicon, on the other hand is just too "good". The result is that just about any silicon based Fuzz Face I've ever heard (or built) ends up with the "ice pick in the forehead" sound.
 
You must log in or register to reply here.
Back
Top Bottom