For your fuzz-o-riffic pleasure - the Chronometric Fuzz

[tcobretti]

For the regulars, this will be a fairly obvious way to create a fuzz pedal, but I think the end result is very nice. At less than max gain, it is very volume knob sensitive, so it might be a good substitute for a FF or even a Axis Fuzz.  The switchable input cap is not so great in its current configuration, but since it is on the layout I left it on the schem.  If you build it, I recommend trying a larger value in place of the .0047u; it filters too much of the input signal (.01u might be a good place to start).  You could even try a .1u and see what happens.  Also, the fuzz pot could be a smaller value; 5k would probly work just as well.





PCB Layout
http://aronnelson.com/gallery/albums/album161/TB_Chrono_Fuzz_Layout.jpg
http://aronnelson.com/gallery/albums/album161/TB_Chrono_Fuzz_PCB.gif


Sound Clips
Les Paul Custom into a Fender Blackface with fuzz maxed (I switch P/Us midway thru)
http://aronnelson.com/gallery/albums/album166/LP_Fender_Blackface_Max_Fuzz_Sw_PUs.mp3

Les Paul Custom into a Fender Blackface with fuzz at about 9 and I play with the guitar's volume knob as I play
http://aronnelson.com/gallery/albums/album166/LP_Fender_Blackface_Vol_Knob.mp3

Les Paul Custom into a Marshall Plexi with fuzz maxed
http://aronnelson.com/gallery/albums/album166/LP_Marshall_Plexi_Max_Fuzz.mp3

Les Paul Custom into a Marshall Plexi with fuzz at about 9 and I play with the guitar's volume knob as I play
http://aronnelson.com/gallery/albums/album166/LP_Marshall_Plexi_Vol_Knob.mp3

[Dragonfly]

Nice ! Another cool fuzz to add to the list !

[Ivana]

For the next time - if it would too difficult to you to create a picture you may say only few words - for example "Brian May treble booster with swichable input cap into 1-st cascade of the FY-2 or other similar fuzz-rite-y designs with 5 k emitter gain control".

[tcobretti]

Yeah, you are probly right.  Maybe by explaining how I cobbled it together the newer members would get more out of it.

[Gus]

your input cap wiring is not a good design IMO.  Wire the .0047uf in all the time then just switch in the .047uf the .0047uf is so small compared to the .047 it should not change the sound that much if it does try a smaller cap for the .047uf. 

  Two things one you can use a SPST two the pop when switching input caps might be less. 

[tcobretti]

This is a good point, Gus, and if I rework the layout I'll change the schem.  However, one thing I like is that in its current form it allows the user to select input caps to suit their tastes, kind of a poor man's tweak fuzz.  If I change it, it'll be less flexible in terms of what values can be used.

[Jason Stout]

http://www.play-hookey.com/dc_theory/series_capacitors.html

[jlullo]

travis, i think this sounds really great... and awesome playing!

thank you!

[newbie builder]

Great playing! Dig the sound clips a lot, that sounds great.

What does the .001uf cap tied to the 22k and 2.4k do? Cut out some high treble I'm guessing?

[tcobretti]

Thanks for the compliments, and I suspect that cap actually allows some of the highs to feedback into the "input" of the transistor.  So my fairly uneducated guess is that it would actually boost the highs a bit.

That is a good question!  I hadn't even thought about it.

[Dragonfly]

I wanted to take a second to revisit this fuzz. I haven't built it yet, but in looking at the schem, I was thinking you might get a better control over the fuzz levels if you sub a 2K lin pot for the 2k4 resistor on Q1's emitter, and use a "fixed value" resistor (maybe 2K2?) on Q2's emitter. That would mean you'd use the first stage to control how much the second stage overdrives. It might yeild a better "clean to dirty" gain range.

Had you tried setting it up like this ?

[tcobretti]

It is certainly worth a try.  As it is, when the fuzz pot is lowered it turns the pedal into a more of a distortion, albeit a somewhat fuzzy one.  Now that I think about it, lowering the resistance at Q1's emitter will raise the gain of the stage, right?  That would likely be a good thing.  You would want to use more than 2k, though.  I'm thinking a 5k pot might be a good place to start.  That way you can clean the pedal up a little if you want to.

The beauty of this pedal emerges when you manipulate your guitar's volume knob.  It's smooths out into a nice overdrive when the vol is on about 5 on my Les Paul, but is full blown fuzzy kazoo when the knob is on 10.  I'd be curious to see how your fuzz pot idea would affect this characteristic of the pedal.  I have been incredibly busy, but maybe i'll get to check it out this week.

[JimRayden]

Hmm I was about to build another Bazz Fuss but now I'm really thinking of reconsidering. Would it be of any trouble to record a strat-clip?

---------
Jimbo

[Dragonfly]

The beauty of this pedal emerges when you manipulate your guitar's volume knob.  It's smooths out into a nice overdrive when the vol is on about 5 on my Les Paul, but is full blown fuzzy kazoo when the knob is on 10.  I'd be curious to see how your fuzz pot idea would affect this characteristic of the pedal.  I have been incredibly busy, but maybe i'll get to check it out this week.

You might also look at adding a pot (250k-500k)to the front of the circuit...lug 3 from input ...lug 2 to the input cap...lug 1 N.C. ....

[Steben]

Great playing! Dig the sound clips a lot, that sounds great.

What does the .001uf cap tied to the 22k and 2.4k do? Cut out some high treble I'm guessing?

Actually it is a bootstrapping device (creating a "fake" high input impedance), but a very subtle one, since that 47µ cap is there to ground. If that cap is omitted, the gain is smaller, but you have a high input impedance. But then again, the bias resistors are "small" too to achieve very large input Z.

So if you want a replacement for the "bright - high Z" Axis Fuzz, try the following:
Omit the gain pot or change it with a small resistor and put a pot or resistor in series with the 47µ cap on Q1. Than swap the bias resistor from 100k-22k to 1M-250k. Instant higher input Z.

[John Lyons]

Nice one! Clips sound nice and there is a good variety of chubby and skinny sounds.

John

[tcobretti]

Great playing! Dig the sound clips a lot, that sounds great.

What does the .001uf cap tied to the 22k and 2.4k do? Cut out some high treble I'm guessing?

Actually it is a bootstrapping device (creating a "fake" high input impedance), but a very subtle one, since that 47µ cap is there to ground. If that cap is omitted, the gain is smaller, but you have a high input impedance. But then again, the bias resistors are "small" too to achieve very large input Z.

So if you want a replacement for the "bright - high Z" Axis Fuzz, try the following:
Omit the gain pot or change it with a small resistor and put a pot or resistor in series with the 47µ cap on Q1. Than swap the bias resistor from 100k-22k to 1M-250k. Instant higher input Z.

This is great stuff!  I had wondered what that cap did.


I had thought about the pre-gain pot, but I figured it was similar to using the guitar's pot to control the input level.  Am I wrong?


Thanks for the kind words, John.  I think that some people will likely love this pedal; it can be very fuzzy and clean up very nicely.  It's kind of like an Axis Fuzz on steriods.  I do think it could likely be improved upon with experimentation, and the fuzz control seems like a good place to start.

[Dragonfly]

I had thought about the pre-gain pot, but I figured it was similar to using the guitar's pot to control the input level.  Am I wrong?

Actually, my understanding is that if you connect is as i mention (leaving lug 1 with no connection to ground), it will affect the input impedance, and may make it better with a wider variety of pickups / pedals / guitars.

[tcobretti]

I had thought about the pre-gain pot, but I figured it was similar to using the guitar's pot to control the input level.  Am I wrong?

Actually, my understanding is that if you connect is as i mention (leaving lug 1 with no connection to ground), it will affect the input impedance, and may make it better with a wider variety of pickups / pedals / guitars.

It definitely seems like a good idea; I am concerned that maybe this pedal won't be as good with a Strat because it seems so sensitive to input level.

BTW, Jim I'll make you a clip when I can, but my recording computer has taken a crap and it'll likely be a week before I can get it up again.

[goosonique]

How bout makin that input cap variable like how its done on the fat boost after the buff !!??