Tuesday, 29 January 2013

ETI Fuzz Struzz (a.k.a. Guitar Effects Unit)

There was a mistake on the layout, that's now fixed. This calls for both +9V and -9V supply. Use of inverter pump daughter board is recommended.

The GEU is good sounding octave fuzz, with an optional mode of just fuzz. The fuzz is a fully rectified signal and is quite chewy. For some the Fuzz alone might not be loud enough, this can be fixed by raising the value of the 820 ohm resistor and lowering the 39k one. Or one could just replace both with a normal volume pot for a more standard approach. The "struzz" is the fuzz with an octave higher signal mixed in. Good for singal notes and leads.


Seems like i'm on fire with the requests today...

Here's Pete Moore's RangePig - an adaptation of Rangemaster with single low gain germanium transistor configured with modern silicon counterpart as darlington. Note that this is a positive ground effect, so you can't daisy chain this with other boxes that use negative ground. A simple pump is always your friend.

Tech21 XXL

Per request. The original design had couple of things i had to mod to get this stripboard and/or 1590B friendly. First, there are two dual opamps in the original box, and they are used in quite peculiar manner. The first one is TL072, which has other half as input buffer for bypassed signal and other half as first gain stage. Which is fine, until... The second opamp is TLC2262, which has its other half as output buffer for bypassed signal and the other as second gain stage. Since onlythe output buffer is after the gain stages, it should not hurt the sound to omit both buffers. But there's little sense in drawing this with two dual opamps and only use other halves.. So i just used one dual - exactly like all the other aproximations/layouts found on the web. There was another little thing.. As with a few other designs, the volume pot is sometimes used to dump the signal to Vref instead of ground. This is ok, but it just means that we need to have a decoupler capacitor before the conventional volume control. I used 2µ2, which is the same value used as output cap at the buffered output. These *shouldn't* affect the sound, but only way to tell... is that someone builds it :)

Geiri's demo of his build:

Lava Rim 2

Another request. Aron Nelson's Lava Rim 2. I have no clue why the input level control pot is called "Bias". That's the reason why i used quote marks around it...

Illumist JFET Boost

From Solgrind blog. Simple, but apparently great sounding addition to mini booster pot. And nice reason to source some JFETs with DGS pinout - Just in case you didn't have any :D

MXR Distortion+ w/ Wampler mods

Another request. Wampler's mods for MXR Distrotion +, as seen at Premier Guitar magazine's website.

Dragonfly Sparkle Boost


Pit Fighter

And another request. From Culturejam designs.

Note from the Man himself: I'd recommend going with a higher value for that 47R resistor. Try 220R, 330R, or 470R. Or even a little higher. The lower the value, the more gain there is, but it's really noisy at 47R. Like, unusable noisy, at least on my test build.

Really Simple Transistor Compressor


Monday, 28 January 2013

ARC Effects B3

This is ARC Effects take on the Burns Buzzaround with a negative voltage inverter to provide -9V to allow you to maintain a daisy chainable negative ground, but use the better quality PNP germanium transistors.  This is a mojo version as per the first edition of the pedal.

ARC Effects make some fantastic pedals and has some of the highest build quality I've seen in commercial pedals, and I would wholeheartedly recommend their pedals to anyone if you're in the market for something they make.

Catalinbread SCOD

On hold for now, pending verified schematic.

Sunday, 27 January 2013

Emerson Custom Guitars Em-Drive

This is a really simple circuit looking at the board, but we didn't have a pic of the back and on the breadboard my suggestions didn't sound right, so I shelved it for a while until I could get a look at the unit myself or at least a decent pic of the rear of the board.

peavey_xxl on the forum posted a link to a schematic that he said someone who built a clone referred him to and so here's the layout based on that scheme. I have done the layout with the same mojo paper in oil caps in mind that were used in the original.

Updates 30th Jan 2013 - Pot value established and corrected, thanks peavey_xxl

Info about the original:

EM-Drive Transparent Overdrive:
Handwired, Handbuilt in Broken Arrow, Oklahoma USA using some of the finest quality & reliable parts available. This pedal does everything from a slight boost/sparkle to a nice, warm light OD sound. Good for use as a first stage OD or a nice boost pedal.... you may find yourself leaving this on the entire gig!

-NOS PIO (New Old Stock Paper In Oil) capacitors
-Handwired Construction
-Quality High Tolerance CTS Pots (Hand Metered & Matched)
-Durable Turquoise powdercoated finish
-Davies knobs
-USA Switchcraft jacks
-3PDT True Bypass Footswitch
-Hand picked and matched parts for tone and durability
-Power: Standard 9 volt DC power supply with a negative center 2.1mm barrel, NO internal battery option.

and a compact version for those without mojo tastes :o)

Suhr Riot - Fixed

I've put a couple of Suhr Riot layouts on here, one from Madbean's take on it, and one with jymaze's popular modifications, but it was always felt that something wasn't quite right.  Fortunately MarkGor on Freestompboxes traced his pedal and also removed some of the components so they could be measured to check the values, and the following layout is based on his schematic.  So thanks Mark!

A quick reminder:

Saturday, 26 January 2013

MXR Commande Overdrive

This makes it 98. Been one hell of a month in so many ways. Before i figure out what to draw as number 100 (yeah, you're right - we'll need two more after that, since there's two notification posts this month), i thought i draw up something that apparently is the worst overdrive pedal in the whole stompbox history. MXR has made one set of plastic boxes, that doesn't get any praise anywhere. Or i haven't just found any.. This is the overdrive from that set. Schematic suggests that it's pretty basic overdrive design with some out-of-the-box thinking. Someone with open mind should build it and tell us if it is really that bad... :)

Jen Fuzz III

Pretty close to the earlier version of Jen Fuzz, and i may have promised not to do Fuzz Faces nor Benders, but here i go again... Seems to be a classic - so some of you might want to clone this one to the specs too.

Fulltone 69

Request.  As everyone knows this is Mike Fuller's version of the Fuzz Face, but it has something that we haven't included in the multitude of Fuzz Face layouts we have on the site so I thought it was worth adding a mojo layout.  Sticking two fingers up at convention Mike called what most would consider to be the bias pot "Contour", and a pre-effect level control "Bias".  So just to confuse matters further the trimmer which biases Q2 is part of the Contour circuit (doh!).  But they all make things sound a bit different so you can call them what you like I suppose.

This is a positive ground effect which can't be daisy chained with your run of the mill negative ground pedals, so consider including the negative voltage inverter circuit to provide the -9V which will make this daisy chain-able (is that a real word?).  That is my favoured way by far to deal with positive ground effects because it also allows you to use the much more consistent PNP transistors and so not have to take a gamble of hit and miss NPN germaniums.

Info from Mike about his original:

This is how you wished your Fuzzface sounded... Fat and Harmonic. And it cleans up like a vintage Fender amp when you turn down your guitar's volume control. The Rolling Stones and the Black Crowes have discovered this trick.

If you love the first 2 Hendrix releases then you'll love this pedal, with 2 Germanium transistors hand-picked and tested for optimum performance. A Contour Knob lets you dial in Midrange, Harmonics and Sustain, also an Input Bias knob that takes out the "woofiness" and gives great Overdrive/Distortion sounds when its level is reduced. An Internal Trimmer allows for adjustment of Clipping Symmetry, Harmonics, and Tracking.

Specifications subject to change at any given moment due to availability... and whimsy.

Alrighty then ...

Friday, 25 January 2013

BBE Green Screamer

The Green Screamer is an overdrive pedal that produces a dynamic range of smooth and warm overdrive tones associated with vintage tube amps. Robust build quality and rugged engineering ensure that the Green Screamer will stand up to the abuse of life on the road. Other features include hardwire bypass, LED operation indicator, non-slip rubber bottom, easy-access 9v battery compartment and included external power supply.

DOD FX55-B Supra Distortion

Why not repeat the same perfect scheme that worked pretty well ten years earlier?

DOD FX55 Distortion

This one apparently has the same circuit board as the FX50. Original used TL062, so TL061 is probably the right chip for the job. Like FX50, the other half of the opamp didn't touch the signal path when engaged at all, so i decided to go with a single.

DOD FX50-B Overdrive Plus

Here's DOD's step up from FX50 :)

Just finished building this. The pot tapers are not mentioned in the schematic, so i went with the usual tapers from most designs. However. Volume needs to be linear and drive reverse log to get the circuit act like the original unit. Other thing was the 470R resistor on the bottom left. 470R gave me lots of oscillation when gain was cranked, so i swapped that to 4K7, which fixed the problem. I do believe that's an error in the schematic i did this from, but i can't be certain. Anyway - it works like a charm and is very nice OD indeed. Fat and smooth.

DOD FX50 Overdrive Preamp

Here's DOD's step up from OD250 - from around '82.

On the original unit, the chip used is TL022, which is low power dual opamp - But the other half doesn't touch the effect side at all - It's only used as a buffer for the bypassed signal. So i made the layout to house a single opamp instead. TL061 is low power single opamp from the same family of chips - so i believe it should sound pretty close to the original.

Marshall Shredmaster

As requested. Someone should get a video of Madferret doing his dance...

Thursday, 24 January 2013

One Knob Big Muff

Request.  This is a One Knob Big Muff based on Joe Gagan's schematic and values. It makes sense in a lot of ways because many people dime the gain controls anyway, but you may want to experiment with the 39K and 47n from Q3 collector to Q4 base to get the tone setting the way you want it.  As usual socket and experiment.

Fulltone RTO Robin Trower Overdrive

Info about the original:

Robin Trower is known for TONE. While working with Robin during his 2008 tour, I developed an overdrive truly worthy of the Trower namesake.

Touch responsive, huge sounding, sustain for days... and crystal clear when the guitar's volume knob is reduced for great live dynamics. Being that Robin uses Fenders as well as Marshalls, it had to work well with both types... and it does. And Robin hits so hard that the front end of the pedal had to be tuned for those .012-.048 tuned-down strings. The RTO holds tight and smooth for Strat and Les Paul players alike.

Robin's quite happy with the way it turned out, and I think you will be too.

Here's Geiri's build, with AMZ mini-booster in front of it:

Wednesday, 23 January 2013

Clipper Ship v2

Cool sounding dirty booster from Jon Patton:
Clipper Ship Overdrive. This is a dirty boost cascaded into a FET-based booster (a tweaked version of R.G. Keen’s “SRPP,” based on the AMZ Mini Booster). The gain control goes from clean to fuzzy, but the pedal always cleans up with your guitar’s volume, making it a very open and touch sensitive dirt pedal. And the boost stage has gobs of output to push your amp into its own overdrive. A “stupidly wonderful tone control” allows for treble boost clockwise and treble cut counterclockwise. This build used a Russian germanium transistor for the dirt side and germanium diodes.  The overall character is kind of Vox-y.

Edited notes from the schematic files:
Q1: Any Ge or Si. Germanium with hfe 40-70 sounded best to me and cleaned up well. Q2 & Q3: 2N5457, J201, or other JFET.
Ge1, G2: Diodes should have a Fv < .3v for best performance. Many schotkey diodes will also work great. Red Ge diode prevents temperature changes from affecting the leakage of a Ge transistor. Omit if using a silicon in Q1.
My prototype of version 2.0 used a russian MP38A Ge transistor in Q1 (~61 hfe, leakage ~ 60uA) and Smallbear "Generic" Ge diodes.
This is interesting: ANY transistor will work in Q1 ... including PNP. I can't really recommend using a PNP without more information on why it worked, though.

Briggs' Unknown Fuzz

So as i was drawing up the Briggs' designs...
A new fuzz design from myself. It's silicon transistor based but with a difference. I've been playing around with the old Vox Tonebender circuit for a while and this is what sprung from those experimentsTaking inspiration from the Fred Briggs Fuzz I made a few years ago that used "piggy-backed" silicon transistors to emulate lower gain germanium devices I used a couple of piggy backed high gain silicon trannys in the first stage with the hfe set to 25. This first stage pushes a NOS BC108 transistor in the second stage - it sounds great, there's no ear shredding like the usual silicon fuzz boxes just a nice fat low end and a warm mid section. The three controls are for 1; a bass cut, 2; a width control (which adjusts how "wide" and gainy the fuzz sounds) and the third is just a volume control. As you can see there is no "usual" gain control, that's because the only gain control you need is your guitar's volume knob, it'll do everything from mild overdrive right through to full on FuZzZzZzZz.

Briggs' 'Face

Simple, yet good sounding booster/OD, emulating the sounds of Black/Brown/Silver-face amps. This one can be run from  4.5V all the way up to 18V. So You could of course run it with 9V, but consider using a charge pump to double it up to 18V. And yes. I do believe it'll work well with 5K trimmer :)

From Mr. Briggs: I really like this one, it's a booster/overdrive with a nice Fendery feel and voice to it. As you can see there are some values which you can alter on the schematic that allow you to tailor the tone to your exact needs. Firstly the supply voltage - the lower the voltage the less overall gain and clipping you'll get, more voltage = more gain and clipping. The jfet choice also makes a difference to the tone of the circuit; 2N5457s give more gain but are more compressed sounding (better for the Fender "tweed" emulation) than the MPF102s (better for the larger Fender "twin" type emulation) which have more headroom but less gain. You can use almost any jfet type in this circuit 2N5458, J201 (I didn't like these, they were too compressed and gainy - almost fuzzy!), you just need to find your type! If you want to learn a little about jfet's and their properties check out this article over at runoffgroove: http://www.runoffgroove.com/fetzervalve.html. Finally the 3n3 tone cap can be altered to your preference, a higher value will lower the high end gain, a lower value will allow more high end drive.

In my final build I'll be using MPF102 jfets running at 18V with a 4n7 tone cap to keep the high end under control. This setup provides a nice "cranked twin" tone and is really dynamic and reactive to your playing, a decent low end is retained while it still fizzes out at higher gains.

Tuesday, 22 January 2013

Cable tester

Well.. This was requested, and first i thought that nah. Not gonna do it. But after thinking about it for a few seconds, it didn't feel like that bad of an idea. So i drew up simplest "original" design i could ever do. The idea is that you attach a cable to two shielded jacks. There are LEDs for both, the core and the shield wire of the cable. If the connection is solid, then the LED will stay lit. If wiggling the cable makes the LED blink or they don't light up at all - well then. You better get a new cable. I made two versions. One with completely unnecessary switches and the other with just simplest wiring i could come up with. This may be useful little utility for some people - and maybe even a nice purpose for those tiny leftover pieces of board :)

Anyway. Use shielded phone jacks and dc jack - stuff them into 1590A - Instant cable tester. This one  won't probably need a verified tag :)

DeArmond Square Wave Distortion Generator

Now this one is quite a mystery to me. Analogguru's schematic matches the gutshot at the effectsdatabase, yet the demo suggests something quite different from your average Dist+/250 clone. Schematic states that the pot values are guesses, but there are clone build reports around the web.. So. However it may be. Here it is. The Almighty DeArmond Square Wave Distortion Generator.

Briggs' E11even

From Mr. Briggs: And here's the last in my series of Fender / Vox / Marshall themed boosters/overdrives - The "E11even" (Spinal Tap reference intentional). It's designed for those classic Marshall overdrive tones, plexi / jtm45 sort of stuff. It's based around the old mosfet booster design I love with a few tweaks. The bias control is essentailly a saturation control for those diodes, setting it high gives you more headroom and a smoother more spanky (hehe) overdrive, a lower setting gives a more gritty tone. The Body control allows you to alter the bass content and overall frequency gain structure of the circuit. When the body is at 470k you've got the classic Marshall mid/high boost filter (almost, with that 1M resistor to ground you don't quite get the same level of low end roll off but it works with this setup). One suggestion I have for a mod is placing the saturation control over one diode only so that you can dial in some really interesting (and extreme!) asymmetrical clipping structures...
For the protection diode you can use a 12v zener or just a red LED. I use a 470kB (linear taper) pot for the Body control but some may like the taper of a log pot here - it's up to you...

MAndrews tipped me off about Geiri's excellent demo videos. First with strat and single coils, then with Les Paul and 'buckers:

Briggs' 64 Vintage

As requested. From Mr. Briggs:
Here's another (nearly) new one from me. It's a tricked out super mod of the old Electro Harmonix LPB-1 circuit that produces some lovely singing overdrive tones reminiscent of an old VOX from their 1960's heyday. I took the Lovepedal Englishman (A supposed Vox AC30 / AC15 emulator) as a base and went from there - Firstly I wanted a little more gain, hence the 4k7 collector resistor. Along with more gain I wanted more emphasis and clipping on the higher mids to replicate that treble laden Vox overdrive hence the 82nF bypass cap and the 47k/22nF mids filter at the end of the circuit. These changes make the circuit sound livelier and give it more character. The use of the *super* low forward voltage SB340 diode in combo with the BAT46 diode produces harmonically rick asymmetrical clipping, the levels of which can be controlled using the "Headroom" control. The headroom control also allows a nice rich low end to be retained while allowing the top end to be clipped, as you roll back the clipping a nice tube like "note attack sag" effect becomes prominent - it's quite pleasing and cool to play with. The use of the 2N3565 transistor is due to some tests carried out a while ago where it was found that the 2N3565 sounded best in these sort of applications, you can replace it with a 2N5088 or BC108 or, in fact, any decent gain NPN transistor.

Soulsonic Hunny Bunny

Beautiful sounding overdrive. Check the full descpription and sample at Soulsonic FX website.
A simple opamp/MOSFET overdrive gets a variety of sweet tones.

Fallstaff OD

Fallstaff OD, or "Fat Mastered" from Jon Patton. It's a modern take on Rangemaster with a few quite cool features. I replaced 8K2 resistor from Q2 base to ground with a 20K trimmer for easier biasing.
From Jon: The Fallstaff overdrive (or "Fat Mastered boost") is a variation on the Rangemaster, but with a buffered input stage and a color knob to fatten the sound in a way that offers a nice change from the usual input cap mods. It can be tweaked to sound a lot like a traditional rangemaster, as a full range boost with sparkly top end, or as a dark mids boost. The extra input stage makes the pedal behave the same whether it's before or after another pedal. It provides a 20db of boost or more depending on the gain of the transistors you use. Unity volume on my prototype was about 10:00.

For Q2, values as low as 35hfe were acceptable with proper biasing, but gain ranges around 50-60 are ideal for the values shown. I got decent results with values as high as 120hfe. NPN Si transistors in that range will work, too. R5 and R6 bias Q2, like a rangemaster, to ~7v on the collector. Use sockets or trim pots or breadboard before building if your transistors aren't pretested! Q1 can also be a JFET. I used 2N2925 instead because it sounded really good and I didn't have to twist the leads to get it in the sockets in my layout.

Monday, 21 January 2013

Lardacious Phat Bastard

Pink Jimi Photon is one hell of a dude.

nothing special or probably un-done before....this USED to be the "stereo make up gain stage" i built for my mn3007 clone theory build...
ever eco-conscious <vbg> i decided to cascade the two preamps. and add a footswitchable diode clipper. all built in a re-cycled 1590 from my very second build.
now...it may not seem like much, but it's real nice and creamy!! i built mine with the balls pot on the side of the pedal, so i can roll it with my foot to adjust it. you may wanna do different.
anyways...it's built, it's verified, if you want a schematic, you gotta draw one!!!  it's basically a pair of eh lpb1's cascaded, with a footswitchable diode clipper between e of q2 and ground.
easy breezy sleazy goodness... can double as a fuzz or an overdrive. if you leave off  R9, and turn the gain pot all the way down, you get farty nasty octave down/ringmod/escobedo kinda horrible nasty sounds,
that SOME of you guys may enjoy...i just added the resistor to prevent that, but when ya breadboard this, you may like it better without.
i didn't measure voltages, i cranked the top trimmer full blast, then the bottom up till i found a sweet spot. if you get rf noise, turn vr2 down just an RCH.
there ya have it;
something to do one of these days when you're REALLY freakin' bored!!

Soulsonic Folk Driver

The Folk Driver is the result of a challenge issued to me by Björn Juhl to design an original DIY overdrive project that has much of the character of his popular Honey Bee Overdrive. After some time listening to an original Honey Bee, I came up with the Folk Driver.
Like the Honey Bee, this is best described as a “soft” or “jazz” overdrive, that breaks up more with hard chords than with single notes. The overall voice is warm and musical with a nice harmonic bite.
The Timbre control adjusts both the gain and the tonality simultaneously. At the 12 o’clock position, it is a neutral tone with minimum gain. When turned clockwise, gain increases with the high frequencies emphasized. When turned counterclockwise, gain increases with low frequencies emphasized. This makes it very easy to dial in the sound you want in an intuitive and novel way.

Geiri's demo of his build:

Sunday, 20 January 2013

AMZ Mini-Booster

Jack Orman's DIY classic that has been inspiring many builders and businessmen alike over the years. Simple as Fuzz Face, but very big, strong, lively sound. There must be tens or even hundreds of variations around, just as there must be tens or even hundreds layouts around. Still we didn't have this one covered yet. Now we do.

And Geiri's demo! Sounds great doesn't it!

Colorsound Bass Fuzz

Well. It was either the unused row or two resistors with 7.5mm pitch. Still pretty compact. The clipping diodes are placed so that you can pretty easily take them to a switch and play around with schottkys, LEDs....

Univox SQ-150 Square Wave

And a little clip with a small cap to tame the squeels and a LPB-1 with a trimmer at the output to fix the level issue.

Jen Fuzz

It seems that not all of the sixties fuzzes were verbatim tonebenders. There's not that much difference blueprintwise, but still noticeable difference. Some might want to clone this too...

Geiri modded his build a bit to get its sound closer to his preferences. Some of you might want to try these mods out as well. Word from Geiri and demo of his modded build:
I basically changed the 10nf cap by the input to a 100nf. The 10nf that goes to level 3 changed to a 47nf and I changed the 1.2nf to a 10nf. Very simple and for me, it improved the pedal a lot. the 2k pot was too big before the change and it would start to make noises but after changing the caps, it's fine. I recommend using a 2k pot if you're gonna do these changes. - When you max the gain, it's still quite bright and more like a distortion but if you switch to neck pickups, it goes a lot fuzzier so I kinda like it!

400th Verified Layout!

Another milestone hit, the 400th verified layout which is really amazing. 300 layouts verified since last March!

Thanks to everyone who has contributed to verifications and/or discussions, and to Miro who has really helped me out and is on fire at the moment churning out layouts like a machine. We have so many regular contributors who make the site what it is that it's getting difficult to list you all, but a really huge thank you to everyone.

January is looking like it could be a 100 layout month which would be great.  The site is becoming more popular all the time and we are now getting over 200,000 hits a month, and the addition of the forum I think is really helping to make this feel more like a community.

So thanks again one and all, and Miro is doing the notification for the 500th verified layout so let's get going! :o)

Cheers guys!

Saturday, 19 January 2013

Catalinbread Sagrado Poblano Picoso

I did this one ages ago and never posted it for some reason, so I may as well add it now. Info about the original:

Ah! the Catalinbread Sagrado Poblano Picoso! The Poblano Picoso has many of the great features as the Super Chili Picoso except that the Poblano is tuned for an extended frequency range. This has been one of my most frequently requested modification of the SCP for bass players.

Just because the Sagrado Poblano Picoso is tuned to better suit the range of bass instruments it does not mean it is limited to this application! With gobs of tone drenched boost, it can drive the input of any amp. The trade off for the extended frequency range is reduced headroom. So at it's highest settings you will find that Poblano is a bit more gritty than other 'clean boosts'. The added grit is complimentary to guitars and has the happy side effect of making solid state amps sound warmer. We decided that this was a great pedal when I plugged my P-Bass into the Poblano then into my band's 400W solid state bass amp and was instantly taken back to the first time I experienced the world's greatest bass amp the SVT. We decided to release it to the public as soon as we heard how well it sounded in a guitar rig.

I can't find a demo vid but here's the Super Chili Picoso which is the guitar version:

Smooth Fuzz

Request.  Info about the original project in Practical Electronics:

Of all the effects units for electric guitars, fuzz is undoubtedly the most popular and numerous designs have appeared in Practical Electronics and other magazines over the years. So why yet another fuzz unit?

In principle fuzz is easy to produce; all one has to do is distort the signal. But in practice it is very difficult to obtain just the right amount and the right character of distortion, and most designs end up producing a sound which is unpleasantly harsh and rasping. We know because we have tried many of them. Some designs use a Schmitt trigger circuit to 'square up' the input waveform and these tend to give very poor results as the output remains absolutely constant up to a certain point and then suddenly stops. Also a guitar produces a large transient at the start of a note and in some designs this causes momentary blocking due to coupling capacitors charging up. This produces a disconcerting 'hiccup' in the output.

What the professional musician usually wants is a more refined sound-a fuzz unit which gives the guitar tone which is 'different' rather than obviously distorted and gives a limited sustain without completely destroying the dynamics of the input signal. The unit described here will do just this and that is why we have called it 'smooth fuzz'.


The circuit uses a dual low noise f.e.t. operational amplifier as these devices now offer excellent performance for a very reasonable price.

The first part of the circuit. around IC1 a performs two functions-it provides a voltage gain of about 60 to raise the input signal to a suitable level to operate IC 1 b, and it acts as a low pass filter with a cut-off at about 1kHz and a slope of 18dB per octave. This removes the higher harmonics of the strings and so reduces the number of intermodulation products produced by the following stage. IC1 b is the distortion generator. Very small signals are passed without distortion, but as the output voltage rises above about ±0 · 5 volts diodes 01 and 02 conduct, providing gradual limiting of the signal. The output waveform produced by this stage varies as shown in Fig. 3 as the input signal is increased.

Although the waveform distortion produced by this stage is not excessive the direct output would still be a little too harsh for most peoples tastes, so two stages of additional filtering are provided by R9 and C8 and VR1 and C9. VR1 is the tone control and as it is varied from the C9 end to the C8 end the tone becomes progressively sharper.

Geiri's demo video of his build:

Ibanez PL5 - Powerlead

This is the biggest layout i've done to date. And believe me - four transistors and one dual opamp - that's pretty much all you can fit in there, if you want to squeeze it into 1590B. Anyway. I know that in the first six hours of publishing this there will be at least one dude commenting how it sounded like crap back in '95:) This one - once again without buffers and transistor pinouts are changed to accomodate your standard pinouts of 2N5088, MPSA18 and BC550C. I urge you - do a ebay search with keywords "ibanez soundtank".... The days when you could get one for $10 are gone.

Just finished building this, and in my opinion it's not the best design in soundtank series. But if we think this for two seconds - it is called Powerlead - not bluesy overdrive, nor death metal distortion. I can see this very high gain distortion being useful for leads and solos, but i would'nt use it for base tone. If i was to mod one thing, that would be upping the input cap for something like 100n. And why not add some clipping options or just double the number of diodes for more volume. I used BC549Cs for the transistors. Not sure if the tone pot is reversed or not, but as it is, i would rather call it depth than tone. Tone stack would be one of those places where some cool mod would probably make this a lot better circuit.

There are many varieties of distortion. This is it, and beware: it will add a razor-sharp edge to your noise. The PL5 is the 2nd biggest seller in the Soundtank Series (the TS5 TUBESCREAMER is No.1). the POWERLEAD is a little lighter on the bottom with more mid-to-highs.

Allies Fuzz

Last one from Masaru Kubota's schematics: This fuzz kicks ass.  I revamped Roger Mayer's Axis Fuzz and stuck on a phase stage to make the circuit sound like a tube amp.  You probably notice the Dallas-Arbiter Fuzz Face biasing configuration.  You can use a regular low-pass RC network, ala the ProCo Rat, to make the circuit sound like a "open" tube amp.  This fuzz sounds ALOT like the "Modern Lead" amp model on my Zoom GM-200.  You'll be surprised at how much this circuit sounds like a tube amp.  The only thing "missing" is the desirable, fine-grain, underlying sheen, but who notices at a really loud rock show?  The response feels really good.  It even sounds really good with my horrible-sounding silverface CBS Fender Bassman (complete with aluminum trim and a mis-matched Fender cabinet loaded with P.A. speakers with whizzer cones).  I hereby dedicate this schematic to not my father, my father was one of the Japanese-Americans in the American Internment Camps of World War II, but to Harry Meyer, my mother's first husband, who escaped from East Germany to become a representative of the BRD at the Hague in the Netherlands.  For uniformity, all fixed resistors, except for the power supply resistor and of course the potentiometers, can be 100k resistors, to give a smoother response and for easier assembly.

A little thing worth noting; the schematic calls for 500 ohm pot for fuzz. As those are easily available, but no other design uses them, i sticked with 1K and placed 1K resistor in parallel with it. That makes the taper sort of an log, which might not give you the best feel for the control. So, use 1K pot as stated in the layout, or source some 500 ohm pots, use one of those and remove the 1K resistor between 1M and D1.

The Roseyray

From Mark Hammer: Based on the Voodoo Labs Overdrive pedal, this increases the gain and double clips the signal to provide very heavily distorted signal at the output of IC2 and less overdriven signal at the output of IC1. The tone control blends between the two outputs to morph between two very different sounding distortion. To accentuate their difference, the first one is run through a lowpass filter with a 2.3khz rolloff (6K8/10n), and the second is run through a mid-scooped wide notch filter made up of the 22K/10K/.001µ/.1µ network. This is lifted directly from the classic Univox Superfuzz. Rotating the Tone control blends from a warm overdrive tone an over the top  death metal tone. Settings around the middle give a brighter buzzy kind of sound over top of a moderate distortion.

This is a VERY loud pedal with lot of gain than can easily overdrive your amp's input stage. I used some 190K pots for the tone and volume controls because i had them and needed to use to make use of some custom knobs. 250K pots are the nearest equivalent and should work just fine.

This pedal runs off +9V  dc, and uses a standard dual op-amp and red LEDs.

Geiri's demo: