Fuzz pedal profiling - unpredictable results

    Quote from Gary_W

    For me, part of the joy of a vintage fuzz is the way it interacts with different guitar pickups and the volume pot. If you have any vintage style fuzz (such as those based on a Fuzz Face circuit) then the whole design of the thing is flawed but in a wonderful way..... It makes a circuit with your pickups. A guitar amp or more modern pedal does not do this.


    For this reason, I think a profile of the amp with no fuzz and then use the fuzz in front of the Kemper. I know this isn't what everyone wants to hear but ultimately the Kemper has a high input impedance and so will not act like a fuzz pedal in terms of your guitar volume.


    Just my 2 cents. Or pennies actually as I'm British ;)


    actually, to my knowledge and experience the Fuzz Face is quite unique in this respect (turn down volume just a little and the fuzz is almost competely gone). I have plenty of fuzzes that do not react like that.


    The Fuzz Factory is also known to be very picky about the input, so I wouldn't generalize the here mentioned difficulties with profiling a Fuzz Factory to be the case with all fuzzes. In fact we already have great profiles from the Musket Fuzz and the Pharaoh pedal and more in the rig exchange.


    ;)

    Quote from r_u_sirius

    Yes, I did try a Radial reamping box. The output was surprisingly low, the results not useable.


    What´s the diference between a line output of my RME Fireface, which I use for reamping with the Radial reamping box with excellent results and the direct out of the Kemper?


    I'm guessing the line output of your RME is way louder, and what the reamping box expects. The Kemper must send out test signals at levels somewhat comparable to that of electric guitars.


    Have you tried it yet?
    Pickup Dummies are not required for most connections, but for low impedance input devices such as the fuzz.

    Quote from DonPetersen

    actually, to my knowledge and experience the Fuzz Face is quite unique in this respect (turn down volume just a little and the fuzz is almost competely gone). I have plenty of fuzzes that do not react like that.


    The Fuzz Factory is also known to be very picky about the input, so I wouldn't generalize the here mentioned difficulties with profiling a Fuzz Factory to be the case with all fuzzes. In fact we already have great profiles from the Musket Fuzz and the Pharaoh pedal and more in the rig exchange.


    ;)


    Hi Don,


    You're right that lots of fuzzes don't behave like this, but the Fuzz Face is a long way from being unique. There are lots of very pricey Fuzz pedals out there now which are just tweaked values and mojo germanium transistors in a good old fashioned Fuzz Face circuit. Look at the Analogman fuzz cataloge, the D*A*M catalogue etc. The Tonebender is another classic circuit that loads of makers use to make boutique fuzz. I recon with current fashion about half of what is out there will give you hassle. If it's based on a Muff then it'll be just fine. Based on the above (or several others) then it may give trouble IMO.


    The reason for this is that the input impedance is low and causes you to lose high end frequencies. With this in mind, the rest of the fuzz circuit tends to be built pretty bright (little extra filtering). So when you plug in a guitar straight into a fuzz, the impedance darkens the sound, the rest of the circuit does everything it can to not roll off any more highs. If you have a buffer in there, the high end roll off caused by the input impedance of the fuzz is gone. All the high end gets preserved and the filtering that IS present in the fuzz does nothing to counter this hence it sounding shrill and harsh rather than warm and fuzzy.


    The Fuzz Factory is (once again) based on a vintage design and has low input impedance. The thing that makes it funky and fun is that it has extra controls in there to alter the stability of the circuit. IMO, half the fun of the fuzz face is being able to tweak the knobs whilst you're holding a note to make it do squeaky weird motor boat farty noises on steroids. As a plain fuzz, I much prefer something simpler as the fuzz factory is a picky thing..... It has so many ways to create noise that, if you find a combo of the 5 knobs that sound musical, you need to take a picture so you can get there again - they are crazy-interactive. Please note that I'm basing this opinion on a home made version (the circuit is all over the web) as I'm too tight to buy a real one when I can have fun building one for 1/10th of the price :)


    Don't get me wrong - I'm not saying 'you cannot get good results profiling a fuzz'. As you rightly say, there are some in the exchange that are very nice already so it's worth a crack for anyone out there. But....... it's likely to sound mighty bright if you choose the 'wrong' fuzz and if you do get a sound you like then the whole profile won't react like the original signal chain as far as the picking dynamics / guitar volume rolloff because vintage fuzz does the volume cleanup in an unusual (and addictive) way.


    I would suggest the following acid test to answer the question 'will MY fuzz profile well'.


    Get a pedal with a buffer in it. Boss tuner will do, thousands of others. Anything that does not colour the sound in your opinion when the pedal is in the chain but bypassed.


    Connect guitar > Fuzz > Kemper. Play a profile you like and record a clip. Then connect


    Guitar > buffered pedal on bypass > Fuzz > Kemper. Play the same profile and record a clip.


    If you can't tell the difference, your fuzz pedal has a high input impedance and you can hope for good profiling results.


    If the one with the buffer in the chain sounds like nails down a blackboard, expect your profile to sound like nails down a blackboard too as the profiling process 'adds a buffer'. The good news is the Kemper has far more EQ options than a standard rig so you may still get a result that, whilst not like the original in terms of behaviour, still makes you smile. And that is what it's all about IMO :)


    FWIW, I love my home-made Sunlion pedal in front of the Kemper. With a vintage battery (I did enjoy that recent thread :D )


    So that's a total of 4 cents today so I suppose that'll do :)

    Quote from ckemper

    Have you tried it yet?
    Pickup Dummies are not required for most connections, but for low impedance input devices such as the fuzz.

    yes I did, you can hear the results in my sound example number 4! It made things slightly better IMO, but still too far away from the sound of the simple Gtr->Fuzz->Amp signal chain.


    As I already said, the pickup dummy works great for reamping purposes, but between KPA direct out und the Fuzz Factory it did not solve the problems.


    Your acid test is correct.
    It can be even easier, as the Profiler does a buffer amp.


    Play your guitar first though the Profiler and secondly directly connected to the fuzz.
    If the difference is there, it cannot be profiled.

    Hi Gary_W,


    thanks for your detailed post
    I mean it, no sarcasm here. :)


    I agree, many of the so called boutique fuzzes out there are basically Fuzz Faces with a few minor changes and 'mojo' transistors... :rolleyes:
    I've bought and built quite a few of those myself.


    Even tho the volume roll-off of your guitar isn't 100% the same as it is with a Fuzz Face, I'd like to point out two things:
    1) the Kemper Profiler was specifically developed to profile tube amps - the best known source for 'tone', but it does an amazingly good job in profiling pushed transistors (and clipping diodes and so on).
    2) maybe the profile of a Fuzz Face doesn't react exactly 100% the same when rolling back the volume pot of your guitar, but it still does react in a very musical and useful way - I use it all the time.


    The Fuzz Factory is basically a circuit-bent pedal. It's a very odd, unique specimen. I have three and they all sound and behave differently.


    On the other hand, I have set up a fuzz circuit on protoboard and profiled it repeatedly while swapping transistor combinations and diodes and the Profiler recreated those changes beautifully.
    I've always been about those slightly chaotic, yet very responsive fuzz tones, and the Profiler is the first device to give me those tones consistently.


    For exsample, I can change a generic 1N4148 clipping diode to a NOS Siemens BY250 (good luck finding one of those), profile the circuit and have it available whenever I want to, how cool is that? :D

    Quote from Gary_W

    For me, part of the joy of a vintage fuzz is the way it interacts with different guitar pickups and the volume pot. If you have any vintage style fuzz (such as those based on a Fuzz Face circuit) then the whole design of the thing is flawed but in a wonderful way..... It makes a circuit with your pickups. A guitar amp or more modern pedal does not do this.


    For this reason, I think a profile of the amp with no fuzz and then use the fuzz in front of the Kemper. I know this isn't what everyone wants to hear but ultimately the Kemper has a high input impedance and so will not act like a fuzz pedal in terms of your guitar volume.


    Just my 2 cents. Or pennies actually as I'm British ;)



    The issue is not the high impedance on the input but the low impedance on the output. There had to be a pickup simulator on the output, but might be virtually impossible to configure all PU configurations possible.

    Quote from ckemper

    Your acid test is correct.
    It can be even easier, as the Profiler does a buffer amp.


    Play your guitar first though the Profiler and secondly directly connected to the fuzz.
    If the difference is there, it cannot be profiled.


    If I had a brain I'd have thought of that :whistling: Thank you for the clarification that the overall reasoning on my post is sound to discover 'which fuzz is likely to profile well and which will not' even though my method was a little over-complex :)


    Hi Don,


    Thanks for your reply :)


    I agree, it is indeed very cool that you can do these things with the Kemper. I've got loads of home-made pedals on my board which, in the month since I've had the Kemper, I haven't really played with! I'm still at the 'turn the browse knob and grin' stage so haven't played much with what is down there. Now CK has confirmed my thoughts on the 'bad ones vs good ones' to play with on the fuzz side, I'll experiment. I've got 4 home made fuzz pedals here and they are all 'bad ones'. One is a Fuzz Factory, one is a D*A*M Meathead, one is a Sunlion and the last is a good old fashioned fuzz face. None of them like being after a buffer. I've got other home made stuff on there that will be just fine (Catalinbread pedals, a Klon, a King of Tone, a Zendrive). But TBH the reason I built all of those was to try and make my actual amp sound like something else. In other words variety. That is something I no longer lack since I entered Kemper land!


    I have a Muff ready to build and that is based on the Skreddy version. I recon that would work a treat so may be worth playing with but time is not my friend these days so 'when?' - not sure.