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Here are some of my pedals

Shaka Express -- Hi-gain distortion with mid control.
- Sound Sample
- User Sound Sample

Booster 2.5 FET overdrive
The Booster 2.5 is the next generation of the Booster 2 designed by Jack Orman. I refined the circuit based on the refinements Jack put in his Mini-Tubes pedal. The result is a stunning overdrive that has 90% of the wonderful tone of the Mini-Tubes with about 1/3 of the complexity. A great pedal, I am still enjoying mine. Also check out the Sweet Thing which is Doug Hammond's mods to the Booster 2.5.

Shaka HV Higher Voltage Overdrive
Sound Sample
- 30 volts low to medium drive sample
- 30 volts Hi-drive sample
This one is for the guys that like more clean headroom and very little to medium overdrive. When the drive is turned all the way down, you can a great good clean boost. Runs on 18 volts (2 batteries) and has much less drive than my usual pedals! Easy to build and sounds good. HV = higher voltage. If you run it on 30 volts, then change the drive pot to a 500K.

Shaka Tube Low-voltage op amp->12AX7 overdrive

Hornet Overdrive Fuzz Face-based overdrive
  • Notes: A germanium/silicon transistor hybrid Fuzz Face that screams! High gain, high sustain, ANGRY, yet can get bluesy when your guitar pot is turned down. Minimalistic design that can be "tuned" to perfection. Better watch out cause the Hornet will sting The Rocket! The Hornet did not happen without the contributions of the usual netizens that help us so often. Alfonso Hermida, GFR, Gus Smalley, Jack Orman, R.G. and others. Thank you guys!
7/11/99 -
Notes: Not much to this circuit; the trimpots allow you to really tune in and adjust the circuit. The 2N5088s can be readily found through Mouser. The rest is pretty much Radio Shack or your local store. Convert to PNP transistors by changing the orientation of the lone 47uF electrolytic and reversing the battery polarity. (The battery AND 47uF cap POSITIVE to ground).
Mods: The input cap is critical; for classic fat fuzz tones use 2.2uF to 10uF to larger! (you may consider socketing it - I did) The output cap is less critical; I have found that .1uF is fine for me. The .05uF that I use I have found to be very good because it changes the frequency response of my guitar the least. I have around the same bass as when the unit is bypassed. The trimpots allow you to really tune in the sound. Many shades of distortion will come out as you fool around and turn them. C? is a high end rolloff cap, you can put .001 to .01 to larger values and hear what it does (socket this cap). You can also put the usual 50K pot at the input BEFORE the input cap as described in the Technology of the Fuzz Face - (GEO) Excellent article about the Fuzz Face.
You could also make the 1K resistor off of Q2's collector a 47K, then make the 100K trim a 47K and tap the output off of the junction between the two. This will reduce your output level and make it a lot tamer.
You can order a germanium transistor (NPN) for the Hornet here.

Lava Rim 2 Everything from soft clip to fuzzed tone
The Lava Rim revisited.
Key points about the Lava Rim 2, uses cheap readily available 2N3904 transistors, sounds good and can get creamy - slightly compressed tones with the drive and input pot set low as well as nasty heavier types of distortion. It's also very easy to build and easily adapts to germanium NPN transistors; the trimpots really allow you to dial in a very good tone.
11/29/99 - The Lava Rim 2 is a versatile circuit! You can mix NPN germanium transistors and silicon transistors for a unique sound. The trim pots let you use all types of transistors such as the 2N5088 for more distortion and gain. In addition, the 2nd transistor can use a MOSFET like the 2N7000 or BS170! Just pop in the MOSFET, drain toward V+, source toward ground and adjust the trim pot until you hear good tone! In addition, remove the diodes to really hear the MOSFET. Thanks to Jack Orman for the tip on using a MOSFET for the 2nd transistor!
11/28/99 - to reduce some of the brightness of the pedal, you may want to put a capacitor (.001uF -> .01uF in parallel with the clipping diodes).
11/6/99 - revision 2 - added bounding pot to diodes for more control over diode distortion.

Hot Fuzz Pro BIG BOLD powerful FUZZ
My take on the Colorsound Tone Bender Professional Mark II with the Sweet Thing tone control. I'm still working on this one, so stay tuned. BTW: the "T" next to the pots mean use a trimmer.

Shaka Braddah 3 (SB3) - Nice overdrive!
Check out Jim Radmer's page on the Shaka 3 - sounds samples too!
A new version of the Shaka Braddah (based on a circuit by Jack Orman) that sounds very good. Creamy and smooth with some bite at lower drive settings. Smooth and warm at high drive settings with the FET booster smoothing out the diodes.
The Shaka Braddah III was designed for you to be able to set the tone control (around 8-9 o'clock) to a neutral setting and get a booster/distortion that can make your guitar sound hotter and more vibrant. In addition, when the drive settings are turned up, it should sound like your amp is being cranked up.
Thanks to John Greene for the idea of using MOSFETs as diodes.
Mods to try: 3 or more 1N34a diodes in series on each side of the clipping section. Each diode that you add will raise the clipping threshold and basically allow the Minibooster circuit to distort more before the clipping diodes start adding their sound. What this means is that you will hear more of the FETs before the diodes kick in. In a similar vein, I suppose that you could try 1N914 and 1N4148 diodes for their harsher sound and put then into the circuit. Since I socketed my clipping section, this will be easy for me to try soon. I have tried different ICs (RC4558 and LF353) and although the LF353 sounded different, I still like the sound of the TL072 fine. Try adding the "softness" or clipping threshold control noted in my Simple Mods page.
8/20/00 - Revised drawing. Fixed tone control, removed 100K trim etc....
12/9/99 - Please try different op amps in the Shaka 3 circuit. They make a rather large difference and one that you can fool around with is the TS272CN (part number 511-TS272CN from Mouser). At 72 cents it's a cheap, fun mod. It radically changes the sound of the pedal. The pedal becomes more midrange, distortion is radically different. More sustain at the expense of fidelity. Very interesting.
12/5/99 - If you like highs like I do, remove the 100K trimmer before the Minibooster and change the 10K trimmer on the source of the Minibooster to a 4.7K - that's enough of a trimmer to reduce gain on the Minibooster circuit. The 100K trimmer loads down the circuit and reduces highs a bit.
8/21/99 - There was an omission in the original schematic - my original Shaka III's MiniBooster is also a treble booster. The new schematic reflects this change. With this simple change (1 cap), your Shaka III will be clearer, brighter and punchier.
7/4/99 - current consumption is ~5 mA, not bad.
5/18/99 - Try different tone circuits with the Shaka III. Splice different types of tone circuits after the MiniBooster. Try the RAT tone control and others. I think you will find that the Shaka III circuit is extremely versatile and adapts to different tone controls. The pedal sounds very different when used with different tone circuits.
5/9/99 - Notice that my Shaka III doesn't have the 22K resistor going to ground in the tone control section. This probably explains why my pedal doesn't get the scooped mids if this 22K resistor is there.
4/18/99 - Wired 2 IRF520s as MOSFET diodes with a 1N34a diode attached to the source pin. This arrangement sounds extremely natural to me. Wire 2 of these and reverse them in polarity when attaching them to a circuit just like a diode pair.
Diode is 1N34A, MOSFET is IRF510 or IRF520. Make 2 of these and then use them as diodes in the Shaka III.
4/15/99 - Added a trimpot on the schematic which essentially allows you to control the amount of "clean boost" when the drive is turned all the way down. This trimpot allows you to make your "clean boost" really clean or kinda dirty - you know?
4/11/99 - Tried 4 1N34a diodes on each side for a total of 8 diodes! The diode array tested at ~.822. Very nice... Even more nice dynamics, yet still has a smooth sound. I'm going to try some 1N914 and 1N4148 combinations for asymmetrical and other varieties of distortion. I realized I am able to mount the diodes onto sockets essentially creating a clipping "module". I can plug these modules in anytime for different sounds.
Check out Doug Hammond's Shaka Braddah III mods which he calls the Shaka Braddah IV. I did like the sound of his mods. I find that the Rat circuit seems to produce less highs and this may work for amps which are bright.

The Rocket Rockin' silicon fuzz
A modification of Gus Smalley's 3 Transistor Fuzz I came up with. Build the 3 Transistor Fuzz and this one too! Screaming, smooth and rich. I call it the Rocket because once you turn it on, you take off! Transistor collector voltages: 8.4, 1.957, 3.199
Try substituting .047uF caps for both .01uF caps right after the buffer in the front. You can't miss them, they are the only .01uF caps on the entire board. In addition, I really mellowed out the pedal by putting a .2uF cap (two .1uF caps in parallel) instead of the .1uF in the tone control. Remember that if you use caps larger than .1uF instead of the .01uF caps, you will have to increase the input cap value. Basically two .01uF caps will give you a midrange heavy tone with some bass cut - nice and slicing. Anything more will start giving you a smoother rounder tone and increase bass response.