Thursday, 28 June 2012

Mad Professor Blueberry

Requested by a few people now and I do want to keep the bassists happy too.  In tomorrows blog I'm going to show you how to make pizza boxes, especially for drummers.  Just kidding! :o)

Although the hand built BJF and Mad Professor effects can hurt your wallet, with the new PCB range out they've made them a lot more accessible to the masses.  And as these are great sounding effects and certainly more than Tubescreamers with different input caps, this is another builder that we want to keep making pedals.  Plus Bjorn's a good guy and plays AC/DC and Iron Maiden so I like him! :o)

A few notes: This is small enough to fit in a 1590B with a bit of careful measuring.  Some people have said this is a bass Honey Bee, but doing the layout I found it more similar to the Model H but with diode instead of JFET clipping.  If anyone has trouble with biasing, consider swapping the 30K and 5K6 resistors for appropriate trimmers and aim for around 5 to 5.5V on the JFET drains. 

Info about the original:

BJF design dynamic bass overdrive.

Mad Professor BlueBerry Bass Overdrive (BBBOD) is a high quality dynamic overdrive pedal for electric bass.

It was designed to get light to medium overdrive, reminiscent of vintage tube bass amplifiers.

With the Drive control, you can get natural dynamically controlled overdrive like on those old tube bass amplifiers, or more compressed thick distortion.

At lower drive settings the BBBOD distorts more the harder you strike the strings, and there is no definite clipping point, but rather different shades of distortion as the amplitude changes. Higher settings will give more compressed sounds.

With the clever Nature adjustment one can adjust the tone, and also control what register distorts. From really big and fat with low register distortion to cutting upper midrage solo bass tone.

There is enough volume to use the pedal also as a booster.

While mainly designed for bass guitar, the BBBO can also be used with other instruments for low, dynamically controlled distortion.


VOLUME : controls output

DRIVE: sets the amount of distortion and sustain, as well as the type of distortion.

Lower settings give dynamically controlled overdrive, the unit distorts more the harder you strike the strings and there is no definite clipping point, but rather different shades of distortion as the amplitude changes.

Higher settings will give more compressed sounds.
A good starting point with most basses is fully CCW, turn the knob until you find the overdrive level that suits your playing.

Lower settings are good for old school tube amplifier tone, while higher settings gives denser distortion.

NATURE: is a tonecontrol for filtering and to control what register distorts.
Turning CCW gives more lowend and also distortion in the lower registers.

Turning CW gives an emphasis in the upper midrange for more protruding solo bass tone.


Tuesday, 26 June 2012

Fairfield Circuitry - The Barbershop

Guillaume Fairfield is another one of the good guys who has been very helpful and open about his circuits during discussions on the forums.  If you like the effects then consider supporting the builder and buying something from him in the future.  If you want to try one before you buy then this may be a good starting point.  This layout omits the mosfet used for polarity protection and just uses a Schottky diode instead.

Info from Guillaume about the original:

Have you ever sat in a barber's chair wishing your tone was as slick as your freshly shaved upper lip? With the Barbershop Overdrive on your pedalboard, you could keep your moustache and sound good doing it.

The Barbershop is an original design, not a clone.

Raw, gritty, warm, smooth, open and transparent are all terms that have been used to describe this overdrive. It sounds great with any setup, but truly shines when used to dirty up a tube amp.

Here's demo of Geiri's build. 2N3904 in place of 2N2222:

Monday, 25 June 2012

Fulltone Plimsoul

Now stop moaning! :o)

Info from Fulltone about the original:

For many, many years you've basically had 2 choices for your Overdrive/Distortion pedals: You could either get "Soft-clipped" Bluesy, slightly compressed, (Toob Screemer, FD2, etc.) type Overdrive pedals... or you could get "Hard-Clipped" (OCD, Distortion+, Boss DS-1, etc.) type Distortion pedals.

What if there was a pedal that offered both? There is now... the Patent Pending Fulltone PlimSoul.

PlimSoul has those Softer Bluesey, Compressed capabilities but also has a Second Stage that you can roll in with the turn of a little dial to add that firmer, crunchier, British output tube style Distortion! What's more is you not only hear and feel it... you can SEE the pedal reacting to your every mood via a firey LED that glows brighter and dimmer depending on how distorted it is and how hard you're hitting it.

Touch sensitive? Doesn't get any better.

Clean up with the guitar's volume control? More than any, yes, even more than the OCD.
Speaking of OCD, people ask "What's the comparison?" Easy answer: OCD has an honest flat EQ, won't change your amp's tone. PlimSoul has a gorgeous enhanced Midrange and Lower midrange... excellent to transform a combo into a Marshall-like lead machine, not so necessary if you already have a Marshall-like amp. I use PlimSoul on any combo, I use my OCD on both combos and larger Marshall-style amps/cabinets.

Good with Humbuckers as well as Single coils? Yep.

Does it play nice with other pedals? Yes, it has an Ideal 500K Input Impedance, ideal super low 10K output impedance.

Can I blend the 2 types of Distortion? Yes, and you can have ONLY Soft clipped or ONLY Hard Clipped :)

In a Nutshell? Extremely good Sustain/Feedback qualities, just the right amount of Mids, bottom, Great touch sensitivity, dynamics, and all those in-between shades available when you know how to use your guitar's volume control. I guess I should be flattered, I'm already starting to see pedal builders taking notice and "getting inspired" by the PlimSoul's unique design, which combines independently adjustable soft & hard clipping and successfully emulates the "sag" and other behaviors associated with a tube amp's output section and tube rectifier. With the OCD, I gooped the pcb for 5 years or so to slow them down, but you're now seeing a handful of "OCD inspired" pedals being sold under various names. Now I'm seeing Photoshop renderings popping up from other makers claiming to be developing "emulates output tube distortion" pedals ala Plimsoul. I didn't bother gooping the PlimSoul, but we are well into the Patent process. :)

Not sure exactly how they're hoping to get one seeing as this is basically a Rat and Tubescreamer hybrid (with the two high pass filters at the inverting input of the first opamp - exactly like a Rat) and the pot to control the hard clipping was done by Jack Orman years ago (AMZ saturation control), not to mention dual pot gain control used by Maxon and Klon.  But if they do it will be interesting to see details of the first court case where Fuller tries to defend the technologies he's taken from other very well documented sources.

Saturday, 23 June 2012

EHX 73 Rams Head Big Muff

Another request, there you go Vince! :o)   From a 1974 Electro Harmonix ad:

This fine distortion device is high on sustain and low on distortion.  It is designed for the guitarist who wants his axe to sing like a hummingbird, with sweet violin-like sustaining sound.  The sustain control allows you to optimize long sustain with a hint of harmonic distortion.  Jimi Hendrix relied on the Big Muff for his smooth, mellow, supple Electric Lady sound.


EHX Green Russian Big Muff

Request. From the effectsdatabase website:

A pinch smoother than its American-made comrade, the Russian Muff exhibits slightly less sustain, yet retains that unmistakable Big Muff sound. Prized by bass players for its edge, and sought after by guitarists seeking its unique flavor.

Here's V7 of the Green Russian from 1994 which a few people wanted in the discussion below.

Thursday, 21 June 2012

Sobbat Drive Breaker DB-01

Info from the manufacturer:

Heavy distortion with a unique and driving sustain.  A wide range of distorted frequenies that enable everything from neo classical solos to outstanding riff work, hyper distortion captures it all!
Excellent for single coil Pickups.

Note that the stomp switch isn't wired up in the conventional way.  The effect includes a bypass buffer and so only a SPDT switch is required, or a DPDT if you want to include an LED.

Wednesday, 20 June 2012

200th Verified Layout!

Well the Prescription Electronics Clean Octave Blend has become the 200th verified layout of the site, and even more amazing it was only 3 months ago that I posted a "100th Verified Layout" post!

Again thanks very much for everyone who has joined in, verified layouts, suggested mods, made corrections or just joined in the discussion.  We all learn from each other and so this is great for me too.

Thanks must be made to Vince, Milkit, thetinnedman and timmy amongst many others who have really helped keep the blog moving, and special mention has to be made to Mirosol who has built like a machine for the past couple of months and verified maybe 30 or 40 layouts himself in a very short time.

I don't think we'll reach 300 quite as quickly, I'm slowing down a bit because I've become very busy with work again (as happens from time to time) and so the layouts take a bit of a back seat, so I'm not expecting too many 70 layout months like February in the near future.  But I'm still going to try to get at least 10 new layouts a month posted up which I'm sure will be enough to keep everyone busy enough.

Thanks again guys, this site wouldn't be the same without you


Tuesday, 19 June 2012

Devi Ever Ruby

Info from Devi about the original:

The Ruby is like a Tone Bender, but way classier and secretly more misogynistic.

Short and sweet! :o)

Monday, 18 June 2012

Maxon OD808

Info from Maxon about the reissue:

Originally released in 1979, the Maxon OD808 was one of the first tube-amp overdrive simulators to hit the market. Its smooth, creamy crunch tone caught on quickly, and helped to launch a long line of predecessors as well as imitators. Today, the OD808 design is without a doubt the most used, most imitated and most lauded overdrive circuit of all time. The reason for this is simple ­ tone. Simply put, the OD808 provides the natural, mild overdrive of a tube amp without sacrificing your guitar's original tone. In addition, it can be used as a clean booster to provide increased gain without compromising the sound of your amplifier.

The secret behind the legendary "808 tone" lies in the amplifier section of its circuit. Rather than having an amplifier stage followed by a clipping stage, the Maxon OD808 uses a signal-distorting diode (Panasonic #MA150) that is located in the amplifier stage's negative feedback loop (which also contains the JRC4558 IC chip). Therefore, the Maxon OD808 distorts signal in the amplifier circuit itself which yields a smoother, milder, more natural sounding distortion than a separate clipping stage. This is also the reason that the IC type used in the circuit has such a large impact on the unit's tone. Maxon developed this unique design more than 20 years ago, and while it is commonplace nowadays, back then it was an industry first.

It should be noted that the Reissue Series OD808 uses different output resistors than the original version. After the unit's initial release it was discovered to have a high susceptibility to noise due to static electricity buildup. To improve performance, the positions of the output resistors on the reissue OD808 were reversed and their values increased in order to reduce noise levels. This circuit change has no audible affect on the sound of the unit, save for reducing the noise levels.

Whether it's used as an overdrive or a booster, the Maxon OD808 is the closest you can get to the classic sounds of 1970's rock guitar in a compact effect pedal.


Thursday, 14 June 2012

T-Rex Mudhoney

Info about the original:

Mark Sullivan from wrote this

The Mudhoney is a Distortion/Fuzz pedal with a very wide tonal range. It features a typical 3-knob gain/volume/tone layout plus a boost switch. I played this for a few minutes with the boost off and it is quite impressive; very thick tone with warmth that could quickly find its way to being your main dirt for jazz, blues, etc. Then I pushed the boost and cranked up the gain! The speakers in my little Princeton cried for mercy. Hitting it with the bridge pickup of a Les Paul brought sustain of Spinal Tap proportions. Chords were a menacing wall of sound but yet unlike its name would imply, the Mudhoney didn’t get muddy and muffled. Note and harmonic separation was impressive giving a very dimensional sound at gain levels where most pedals sound flat.


This baby is designed for those who want an in-your-face wall of guitar sound jumping of the speakers.

The boost button and the tone knob enable you to dial in every sound you like right from ultra fuzz to smooth jazz sounds.

In "OFF-MODE" (with the boost-function bypassed) the Mudhoney delivers moderate gain and a smooth rich sound favoured by many jazz-guitarists.
For a more hairy sound, -just hit that "boost-button" and feel the rumble from hell.

The BOOST button switches between moderate- and high gain.

The GAIN knob controls the distortion amount.

The LEVEL knob sets the overall volume
In mid-position (twelve o’clock) the volume level is 1:1. When turned full over (clockwise) the input signal is boosted 15dB.

The TONE knob affects the top end (edge) of your signal without compromising sonic quality, allowing you to dial in the perfect tonal flavour for you taste.

Thursday, 7 June 2012

Wampler Tweed '57

Info about the original:

The Wampler Tweed 57 is the heart and soul of a mids 50s Fender Tweed amp. Just think Eric Clapton playing Layla: that tiny Fender pushed to the absolute limit for that crunchy yet 100% Fender tone.

We all know that when you need a pedal that nails the sound of an amp there's only one place to turn: Brian Wampler obsessively A/B tests his boutique pedals with the real deal to make sure that the tone is nailed, especially the details that other amp emulators miss like the way the overdrive reacts to gentle playing or rolled off volume/tone.

As well as EQ and Gain controls the Wampler Tweed 57 features an input simulator, an important detail for getting the authentic fender sound!

Wednesday, 6 June 2012

Menatone Blue Collar (early version)

Manufacturers description of the original:

FAT,FAT, FAT. Did i mention FAT? That might be the best word to describe the Menatone Blue Collar.  Absolutely brilliant on a Strat is another way I've heard.  Creamy and syrupy with greasy overtones is a third. This was my second production pedal.  I launched it in January of 1997 as the other side of the coin to the open sounding Red Snapper. The Blue Collar is a compressed, mid hump, singing bluesy overdrive that just seems to sit in the mix without any fuss.  Its presence control lets you dial in just the right amount of "pick attack" so that you can sound thick as molasses but still cut through.  Did I mention the Blue Collar is absolutely brilliant with a Strat?

Video of the newer version but should still give you a good idea:

Monday, 4 June 2012

Way Huge Red Llama

Info from the manufacturer:

The often imitated but never duplicated thunder of the Red Llama is back! This is not a reproduction, but a continuation of where the groundbreaking archetype left off in 1999. Every single feature that made the Red Llama so mighty is still in place, right where Mr. Huge left them. Season to taste any amp, big or small, clean or dirty the Llama is the perfect compliment to them all, with a rich harmonic palette available on the austere control panel. Spin the drive knob and go from a gentle grind all the way up to massive distortion. Use lower settings for defined open chording or juiced clean tones. Go a little higher for crunchy power fifths, and crank it up for buttery lead tones and tight, bottom-heavy riffage. The volume control sets the desired amount of overall level, but be forewarned: The output capabilities of the Red Llama are legendary, with more than enough gain to force even the cleanest, most stubborn amps to submit their headroom.

Make sure you get the unbuffered CD4049 (CD4049UBE, MC14049UBCP etc).  This one is verified:

Demo of Geiri's build:

Sunday, 3 June 2012

Lovepedal Silicon Fuzzmaster

Request.  This was traced from some pics and a PCB layout.  It's a negative ground YAFF with PNP silicon transistors for some reason.

From the Lovepedal spiel:

Your quest for the ultimate Fuzz ends here.

Lots of players use it like an OD pedal or full on fuzz, even distortion.. Roll back the guitar's volume and you're left with a lively shimmer atop your guitar and amp's identity. Amazingly, this happens to an appropriate degree throughout the pedal's range, and without the annoyingly excessive boost in volume that many overdrive pedals generate. And, yes, it's dead quiet.

The Fuzzmaster is a VERY sweet, smooth, silicon transistor based, fuzz that is warm, organic and sings with sustain. While it has an UN-mistakable vintage tendency, it also has a unique voice. Vintage Fuzz Face tonal heaven and everything in between, even tweed amp tones are in there.

The traced schematic:

The last layout (Rev 2) seems to be fine so if you're building it don't worry, but it occurred to me that if I move a couple of the resistors around then I can save an extra column and so the following revised layout does that.  In fact if you get rid of the completely unnecessary 100n filter cap at the bottom right hand side you could save another column as well.  I'll leave that up to you though.

And a final compact version without the unnecessary 100n filter cap.  Just build whichever one you like! :o)

Update: Schematic and layout now done from the corrected PCB layout.  As an option try 33pf-47pf caps between collector and base on both transistors to help smooth things out. 

Saturday, 2 June 2012

NPN Silicon Fuzz Face - Germanium Emulation

From an older thread on FSB and DIYSB about using two pairs of piggybacked silicon transistors to have control over the gain.  To paraphrase, these were the main points:

1. Take two identical random silicon transistors (for more mojo: your fav fuzz silicons)
2. Tie the BASES together,
3. Cut off one COLLECTOR
4. connect a 3k to 6k resistor between the EMITTER of the collectorless device and the EMITTER of the other transistor.

Someone mentioned using a 200K trimmer but I suspect that would be too high and that a 20K trimmer would probably be fine with most common transistors, allowing better resolution in fine tuning the gain.

The basic idea is that altering the resistance between the two emitters using a trimmer allows you to control the gain of the transistor pair, which lets you fine tune an effect to get the sweet spot of gain every time.

This could be used on any of the classic germanium effects, but I thought I'd try it first with a Fuzz Face to see what the results would be like.

Redhouse on FSB wrote:

How does it sound? ...IMHO with the right resistor it sounds much better than Ge's, stays tight in the low end where Ge's start to mush-out, much less noise (hiss) and you get away from that temperature problem the Ge's have.

To find the right resistor for your two transistors temporarily install a 200k trimmer where the resistor goes, plug in your unit and play a playing volume (not bedroom levels) and dial in the trimmer untill you arrive at where you bet the best sound, remove the trimmers and install resistors.

I still have a small stash of AC128 and AC125 I got from a guy in the UK a few years ago (not selling any) I save for Ge builds that "must have" them, but IMHO the Bret-Piggyback thing sounds way better.

Give it a try and see what you think:

And if you want to include a filter cap, which may be a good idea considering how silicon Fuzz Faces can be prone to oscillation: