Rocking in the Plexi world

Plexi Drive for classic plexi tones

1962 was the year that really changed the face and sound of rock'n roll. Not because the Beatles started gigging in Hamburg and not because Maestro issues the first fuzz-tone. More than anything, it was because Marshall first released their JTM 45 30W model. This early rock monster was heavily based on the Fender Bassman but using a 12AX7 tube for pre-amp and used KT66 tubes for the power amp driving a closed back 4X12'' celestion speakers cabinet. This little differences from the original Bassman had a huge impact on the sound and made Marshall a quick predecessor for the older Bassmans and VOX AC50 which were the power horses for early rock'n roll outfits in the UK.

Again, not directly related to the world of fuzz but definitely a cornerstone on the quest. Fuzz, as always, is just fingernails on a chalkboard without the right amp to smooth it out. Marshalls with treble boosters, Fuzz Faces, Octave fuzzes and more.

The JTM name is the acronym for Jim & Terry Marshall. The 45 is for the 45W series which was the upper limit at the time after the 30W series and before the 50W and 100W appeared.

The real deal JTM 45 head MKII

In the mid-60's The JTM 45 became the staple sound source for blues rock bands across the world due to its long sustain, crunchy leads and edgy cleans. It had this edge over Fender and Vox and continued to develop, giving birth to legendary offsprings such as the Marshall Bluesbreaker made famous by Clapton's sound with the Bluesbreakers on the Beano album (hard driven by his Gibson ES-335 and a Dallas Rangemaster), and the powerfull Marshall 1959 Plexi Superlead. It can be regarded that with every generation of Marshall amps, guitar music evolved, from blues to rock to hard rock to metal and so on. The amps and styles are that much interlaced between them.

Number One - The Original 1962 model which the JTM 45 was based upon. 23 units sold and changed history. Today resides in the Marshall museum.

Hendrix used the JTM as his main amp between 1968 and 1969. Angus Young of AC/DC relied heavily on the JTM 45 for his signature guitar tone on early AC/DC albums and live concerts (though he also used the 100W Superlead). Early Gary Moore and Early Peter Green sounds also rely heavily on the JTM 45/100 as the source for their glass shattering solos. It seems that regardless of whether it were humbuckers or single coils, the JTM delivered great clean tones and super dynamic crunch. It takes pedals very well especially if those have a low cut like the Tube screamer or any treble booster. With the bass heavy Fuzz Face it seems strange that Hendrix could get what he got out of this pair,but I guess he did, didn't he? The strat definitely sounds better than the Gibson using this setup.

Hendrix, Page, Yardbirds, The Who, Blackmore and Angus Young.
All of them used a lot of Marshalls and at some point during their early life and their better days played a JTM 45.

The Plexi name came from the plexiglass panel which covered the front side panel on the early models since 1962. In 1967 this panel was replaced with a brushed aluminum panel but the name "plexi" remained as the one-word-description to describe that signature tone to this very day.

Some really great info can be found around the web and here are a few examples:

http://www.legendarytones.com/marshall-shoppers-guide-1/

http://www.marshallamps.com/history/

Anyway, Since I first built the Runoffgroove Thor I have been trying endlessly to nail those early rock tones using various pickups and various rig setups. I did succeed getting a lot of that crunch I wanted but something still kept me up at nights.

1. I couldn't get those clean glassy tones from the Thor, probably because it was a high gain pedal meant to emulate the Superlead 1959 tones.

2. It had some hiss which made it hard for me to use it as the last link in the chain using fuzz pedals or other overdrives.

I had a 2 year tour around every forum known to man, played a lot of MIAB (Marshall in a box) pedals and spent many YouTube hours in order to really understand what pedal I want to build for that particular crunch. I ended up with several candidates all of which try to emulate the Plexi mid-gain overdrive and eventually decided to build the Wampler Plexi-Drive. The reason was two fold: 

A. I had more experience building the Plexi-Drive having built it in the past for a friend and it sounded great what I tested it against the Thor, although not as powerful, of course.

B. It uses standard components like J201 FETs and biasing them using trim pots made it easy to build without too much voodoo.

So, after waiting about a year after, finishing several other DIY projects I came around to this project and after a few evening selecting parts, soldering, assembling and paintings it was done.

Now the Plexi-Drive has a younger brother called Plexi-Drive Deluxe which is even more flexible and has more tone control. The schematic is still not around so I decided to give my Plexi-Drive some mods after searching the forums for some help.

Gut shot of the Plexi Drive based on the TagboardFX layout with biasing trimmers for the JFETs

The first mod I did was lowering the bass boost cap which emulates the 4X12'' cabinet. I ended up using a 1nF cap instead of a 2.2nF which makes the bass less heavy and more transparent. I guss it's a matter of taste and you can also use a 3 pole switch for more than two modes but for me it is enough.

The second is a 1uF cap bypassing the 1st gain stage by pulling the J201's source down to the ground. Although this seems like reducing the amp's gain, it actually boosts the gain up by increasing the volume and preventing the 1st stage from clipping the signal.

Now Brian Wampler indicated that this pedal is somewhere between the lower gain 18W tone and the mid gain JTM  45. I really couldn't tell the difference never having played any of the real deal amps but I can tell you for sure that this is the pedal that I was looking for when I started this Marshall quest. I wanted clean sparkly tones at lower GAIN settings and strong crunch at high GAIN settings with the TONE control compensating where needed. Usually this means that lower GAIN demands higher TONE. The LEVEL control gives you plenty of boost way way above unity and the extra switches give you some more versatility. Different pickups and different boosters really give you a lot of options here.

Mug shot of the modded DIY Wampler Plexi-Drive

I tried to give the pedal the same clean looks which the amp is known for with black and gold colors. I called the bass switch "Cab" and the 1st stage bypass switch "Boost" and now I have a modded Plexi-Drive giving me some great vintage classy tones. Finally I decided to go with a red LED which gives it some extra vintage Marshall looks.

 It sounds great with other pedals in the chain. A treble booster or an overdrive are great to drive it harder and it takes up fuzz pedals very good and probably best with single coils.

So there you have it. A really really great pedal with minimum noise, hiss and unwanted artifacts.

Below you will find 2 tracks that for some reason the Mixcloud shows only one and you can choose "next" to move on to the next one. The first one is to demonstrate the pedal with strong PAF humbuckers and the second with single coils. I play around with the volume knob, various pedal settings, bridge and neck pickups and even some wah or a treble booster in front on a few cases.

You can find the layout I used here:
http://tagboardeffects.blogspot.co.il/2013/09/plexi-drive-with-trimmers.html

The schematic is shown on the Revolution Deux page:
https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiAQlxZl1hMAz3UIwJYt9sUP9SkSAYqJKNbal_nigm2Uko5C1dopC5odZy8zuG8TOXNA-3ms9-x45urWOD_W42-uKIxhNA5FlnTKX6l_0Ysu8H_UqKFU1K94x4WcwD8Sfx4e_U09-Nt0YU/s1600/plexi-drive.PNG

Enjoy!

    

Plexi Drive by Doron Barness on Mixcloud

Fuzzway '67: Revisited

Well it has been a long time since I last revisited the Original 1966 Arbiter PNP Germanium based Fuzz Face. I posted here a while back about my experience with the Fulltone '69 using AC128 trannies which is an enhanced PNP version of the original:

http://fuzzquest.blogspot.com/2012/04/once-i-had-few-germanium-tranny-lying.html

It was a short post and I didn't really use this pedal a lot, mostly because it didn't sit well with my band and because our lead guitarist (although a Hendrix fanatic) could not cope with the over-the-top nature of the pedal. On top of that he plays humbuckers and that made things even worse.

Next I explored the Silicon path and got into building several versions before settling on a slightly revised version of the Fulltone '70. While with the Germanium PNP version I only had a bag of AC128 which I tested for hfe and leakage, tweaking the Silicon NPN with many trannies was a lot of fun and easier due to the vast amount of options at hand. 

http://fuzzquest.blogspot.com/2012/11/the-pink-face.html

If you wanna understand the differences in sound between the Silicon and the Germanium versions try to think about the differences in sound between the early Hendrix Experience era (Ge) and the Gilmour '70s sound (Si), although using different amps and different playing style. Other comparisons are the Hendrix sound of the Experience vs. Band of Gypsys, or Gilmour's sound of '68 vs. '73. It's the rough, bloomy, creamy and deep fuzz of the Germanium trannys vs. the sharper, smoother and edgier sound of the Silicon. Both classic, fantastic and work well with single coil pups, wah pedals and British style cabinets.

Lately I felt that I have neglected the PNP version Fuzz Face and after tinkering with it a bit I decided that it was time to revisit the circuit and see what else could be done to really get that elusive sound and to achieve this critical milestone on my fuzz quest.

So as you know or heard before, the fuzz effect was first accidentally obtained during recording a country song in 1960 by Marty Robbins. Check out this outstanding page for some cool country fuzz recordings including the legendary 1960 bass fuzz using a fried pre-amp channel:

http://blog.wfmu.org/freeform/2007/11/country-fuzz-sp.html . In 1962 the first Maestro Fuzz Tone was sold to achieve all kinds of voicing effects for the guitar, but nobody really got the idea. Once the Rolling Stones released "Satisfaction", fuzz-mania hit the streets and everybody were buying fuzz pedals. Maestro Fuzz Tone (FZ-1, FZ-1A and FZ-1B), Mosrite Fuzzrite and Sam Ash Fuzz Box were the first commercial units on the west side of the atlantic while the Sola Sound (Gary Hurst) and Vox Tone Benders, The JHS Zonk Machine and the Baldwin Burns Buzzaround were the first to emerge on the British island. A year later, in 1966, Arbiter released the first Fuzz Face which was really a clone of the early 1966 Vox Tone Bender (MK1.5) and from all the units around, this was the simplest one. I think this was the first fuzz unit to use a double transistor feedback loop rather than multiple gain stages to achieve the saturated fuzz tone. The Fuzz Face's round shape was conceived by Arbiter while looking on the base of a microphone stand....ok....

Now, it's a simple circuit and because of that each element is critical. Every value makes a difference. 2 coupled transistors working in a voltage feedback biasing mode. Only 3 caps: in, out and the third on the feedback loop. 4 resistors: 2 for biasing the trannies, 1 for the feedback and 1 for the output and biasing together. The basic 2 pots controlling FUZZ and VOLUME are further enhanced by 2 more giving some extra functionality like BIAS which is a pre-gain control and a CONTOUR which controls the body of the output signal.

  

If you wanna read about the various Fuzz Face designs:

http://fuzzcentral.ssguitar.com/fuzzface.php

If you wanna read about the cicuitry of the Fuzz Face you should really check this link: 

http://geofex.com/Article_Folders/fuzzface/fffram.htm

More about the history of Fuzz pedals:

http://www.kitrae.net/music/Fuzz_Big_Muff_Timeline.html

For the circuit I used and tweaked here's the best schematic out there:

http://www.generalguitargadgets.com/pdf/ggg_ff5_sc_b69.pdf?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

A great verified and compact layout is given by mark and mirosol at:

http://tagboardeffects.blogspot.co.il/2013/01/fulltone-69.html

My Psych '67 Fuzz Face clone

I played around with a lot of the values on this one and ended up using the basic Fulltone design as shown on the GGG website. I really enjoy the overwhelming possibilities given by the addition of the BIAS and CONTOUR controls. While the FUZZ pot sounds best at it's max, the true versatility of the sound comes from these extra controls. The BIAS is similar to rolling down your guitar volume which is the most elusive and sweetest spot of the Fuzz Face. It is what Hendrix sounds like when you think he's playing clean but it's so sparkly and biting that you know it ain't clean. The CONTOUR is like a tone or a body control which gives you more control over the spectral envelope of the sound. I like to keep it low so that the fuzz doesn't get too boomy.

What really got me going again with this pedal was changing trannies and re-biasing the 10k pot which had a huge impact on the sound. Low leakage trannies with Q1-70 hfe and Q2-110 hfe gave me the best results which in my opinion is a milder and smoother tone (far away as possible from a muff sound). The 10k pot was tweaked to get about 5.5V at Q2's collector-to-drain with the CONTOUR knob at halfway. 

Other options for tweaking were using a PNP 2N3906 Silicon tranny at Q1 which really gave me surprisingly good sound, lowering the VOLUME pot to 250k which sounded brighter, adding 33pF caps from collector to base on Q2 as suggested by R.G. Keen, and lowering the 100k feedback resistor to get milder effect. None of these options lasted on my build but they are good and are working. I would, however, add a STARVE pot for a dying battery emulation effect and a BRIGHT switch to change the input cap. Maybe later this year....  

Among the many myths around the Fuzz Face some are true, namely, single coil pickups do seem to work best with this circuit. Also, Marshalls, Vox and HiWatt amps sound better than Fenders as far as I can judge. I also found that the Fuzz Face stacks rather well with overdrive pedals behind it and, surprisingly, sounds even better and tighter when I used a treble booster in front of it, although driving it too hard will change the fuzz character. I always thought it was a no no thing, but, it really adds focus and crunch that the original pedal lacks. It made me think of the Keeley Fuzz Head which looks like a Fuzz Face with an added treble booster stage pumping it.

So that's that. Listen to it and build it if you still haven't. It's the real deal. The classic combination 

of Single coils-Fuzz Face-Marshall sounds even better when using a Marshall overdrive pedal like the Runoffgroove Thor. The cabinet emulation is a HiWatt 100W which is really the most transparent classic rock cabinet out there. I tried to cover all bases with the knobs at various positions and playing around with neck and bridge pickups and various volume levels on the guitar. You'll get the idea.

If you wanna turn your Fuzz Face '67 to an AnalogMan Sun Face just use the GGG Boutique '60s Fuzz Face schematic with the following 7 changes:
1. Replace 2u2 input cap with a 1uF one.
2. Replace the 100nF output cap with a 10nF one.
3. Replace 500kA VOLUME pot with a 250kA pot.
4. take the Q2 bias trimmer outside to an external knob for the Sun Dial. Use a 5k pot in series with a fixed 2k2 instead of the 1k fixed with the 10k trimmer.
5. You can leave the 50k input pot or use a trimmer internally like the one in the Sun Face.
6. You can leave the Contour pot or replace it with a fixed 470R instead of the 220R in series with the 1k pot.
7. Try to find the NKT275 germs instead of the AC128 which I normally use.

Tele-(Treble Booster)-Fuzz Face '67-Thor-HiWatt 1 by Doron Barness on Mixcloud

The Real Muff Pie

The Big Muff Pi clone

OK, you guys, we are very close to getting FuzzQuest blog on a climax this time.

If I had to choose 3 fuzz pedals to achieve the widest spectrum of fuzz sounds I would say that the 3 top pedals would be the Maestro Fuzz Tone, The Fuzz Face and the EHX Big Muff Pi (of course I could have chosen 3 other pedals if you asked me that question tomorrow morning). The Maestro Fuzz Tone is what you would call an early fuzz sound (1962-1966), similar in many ways to the early Tone Benders, raspy, buzzy, noisy and grainy like the Fuzzrite, Orpheum and the Super fuzz. The Fuzz Face is the legendary Hendrix or Gilmour fuzz sound (1967-1973), very fat, smooth and much heavier. However, when you take fuzz a step  further (1971-2013) into metal, doom, grunge, acid blues and other heavy rock forms, there is one fuzz to rule them all. It's almost the end of the journey for you if you are after that kind of sound. After that you can maybe chain 2 fuzz pedals in a row, have boosters in front, make some mods to the design, but it doesn't really get any heavier than this (there are some attempts, though...).

The Big Muff Pi pedal is the holy grail of fuzz pedals for many rock guitarists. It's very much like the Tube Screamer in its legendary reputation. Both designs were pretty simple and became the source for numerous versions, clones, re-issues and variants. Both designs became cornerstones in rock history and made a huge impact on the development of rock and guitar sound. You could say that the Tube screamer is the overdrive in the same way that the Big Muff is the Fuzz pedal and it's what many people would describe as the sound of fuzz, without going into details too much.

The Big Muff designed by Bob Myer and Mike Matthews was originally based on the earlier designs of fuzz pedals heavily used by the late great Jimi James, a.k.a. Jimi Hendrix, and was first issued in NYC around 1969. The fuzz that roared out of this pedal was so thick, rich, creamy and heavy that once people started using it, there was no way back. The name Big Muff with the PIE sign is obviously a sex related name (see the 22/7 fuzz post on this blog), based on the association of the word muff pie (oh boy) with the words fuzz, fuzzy, fuzz face and the general habit of pedal designers to name pedals after sexist male associations (Ever heard of the Merkin fuzz?). The pedal retained sound consistency due to the use of Silicon transistors and the use of 4 of them meant you had a buffer pre gain stage, a dual gain stage similar to older designs and an active tone control. Luxurious design! throughout the history of this pedal, various transistors and a lot of the passive parts values changed. Sometimes for getting different sound, but mostly due to changes in the parts inventory of the factory at the time. This resulted in a huge amount of variants. The most famous versions became the Triangle (for the arrangement of the knobs) which is the original design with its silver enclosure, the Ram's Head version which had slightly different values and transistors, the Green Russian made in Russia during the mid-90s with its famous khaki army-like enclosure and the 1977 V4 design with its red and black graphics which became the most famous graphical design for the big muffs re-issues.

Below are two images of typical BMP versions from various eras:

The USA designs from the late 60s through the 70s and the re-issues of the 90s and the 21st century

The Russian designs from the 90s

It would be redundant to go deep into the history and circuit design of this beast of a pedal as there is so much info on the web already. Just take a look at:

http://www.kitrae.net/music/music_big_muff.html

http://www.kitrae.net/music/big_muff_history.html

or

http://www.pisotones.com/BigMuffPi/psst/BMP_versions.htm

a quick version review can be found on:

http://www.kitrae.net/music/music_big_muff_tone_differences.html

On these pages you can find anything from the transistors used on each design, the schematic nuances, the enclosure changes and the artistic graphic designs. Who played what is also probably very interesting for many people. Hendrix used the original version during in his late career, Gilmour started using Big muffs around 1975-1976 and later on. He used the original Triangle version and the Violet and Ram's Head version from the early 70s .Billy Corgan and his Pumpkins used a 1978 op-amp version from 1978 in the Siamese Dream album. 8 tracks of muffed guitars at once all through a Marshall JCM800 with a Strat or a Les Paul. "Huge Huge Sound" was what Billy called it. After the album came out the price of a BMP pedal sky rocketed from 40 bucks to 200 bucks!!! What a comeback. J. Mascis of Dinosaur Jr. and Witch used a lot of early BMP versions throughout his career. He likes to put two in a row for super thunderous muff sound. Jack White of the White Stripes has used the BMP quite extensively although he is also known for using a lot of early fuzz pedals as well. 

A huge list of BMP users can be found on:
http://www.kitrae.net/music/big_muff_users.html

The list includes so many names it's hard to count but just to name a few: Robert Fripp (Guild Foxey Lady 1972-1974), Steve Howe of Yes (Triangle), Thurston Moore and Lee Renaldo of Sonic Youth (Sovtek "Civil War"), Kurt Cobain of Nirvana, John Frusciante of Red Hot Chilli Peppers, The Edge of U2, Pete Townshend of The Who, Dan Aurbach of the Black Keys, Kevin Shields of My Bloody Valentine, Jamie Cook of Arctic Monkeys, Cliff Burton of Metallica, Ace Frehley of Kiss, Jeff Pinkus and Paul Leary of the Butthole Surfers, Stephen Malkmus of Pavement and many many others. 

The ZUS Pi

Enough of the Big muff stories and on to the DIY clone build: My build was made with a wedged enclosure and a circuit design very similar to the Violet Ram's Head BMP from 1973, the early Guild Foxey Lady and also similar to the transistor V4 design from the 1977-1978 era. These versions were known for their use of the 2N5133 transistors. In fact the importance of these trannies is most crucial for the sound on Q2 and Q3. Q1 and Q4 are less critical so I used BC238 trannies which are medium gain trannies. The knobs are chicken black and the 3PDT switch enables true bypass. The sound is pretty amazing, rich and smooth fuzz on any setting. The TONE is super effective and on different areas really changes the sound of the fuzz, it's not the regular passive hi-cut we know from other designs. This is why the BMP tone stack became so popular and was implemented in so many different pedals. The SUSTAIN sounds dull on the minimum setting but anywhere above it is absolutely fuzz-a-licious. I used orange rooster knobs and painted the wedge enclosure with some flame-like brush strokes.

Build any of the versions as shown below:

http://www.generalguitargadgets.com/projects/17-distortion/108-big-muff-pi

or:

http://www.tonepad.com/getFile.asp?id=95

or:

http://www.bigmuffpage.com/Big_Muff_Pi_versions_schematics_part1.html

http://www.bigmuffpage.com/Big_Muff_Pi_versions_schematics_part2.html

http://www.bigmuffpage.com/Big_Muff_Pi_versions_schematics_part3.html

What a huge selection of schematics, hu? Triangle or Ram's Head if you want vintage style. op-amp if you want the Smashing Pumpkins sound, Civil War or Green Russian for that grungy alternative rock sound. This is a monster fuzz any way you build it. Stack two in a row or one with an overdrive behind it or a fuzz face style pedal in front of it and you can get all sorts of fuzz bliss.

Here are some noises I made with my version:

Big Muff clone demo by Doron Barness on Mixcloud

The Pink Face

The Pink Face

Throughout the history of fuzz pedals, fuzz guitarists and psychedelic fuzzy solos, there is no fuzz which has received greater attention than the legendary Fuzz Face. Originally produced by Arbiter Electronics in England and appeared during 1966 the unit was an immediate success. Many of the greatest guitarists in rock history played their best solos and riffs through a Fuzz Face including Hendrix, Gilmour, Blackmore, Harrison, Townsend and many more. Nevertheless, the dependency of the Germanium transistors on temperature resulted in a lack of tone consistency and many players suffered on stage from this effect. To circumvent this issue Dallas Arbiter started issuing Silicon versions of the FF somewhere around 1969 replacing the NKT275 trannies with BC108. Silicon was the new hype at the time and it seemed that by 1970-71 everybody was switching to Silicon faces. Hendrix's Band of Gypsys, Gilmour on all PF albums and tours since 1971 including all of the solos on Meddle and Dark side of the Moon are probably the most documented examples. One of my favorite guitarists Michael Karoli (Can) also used Silicon Fuzz Faces to create his raw and untamed distortion throughout the history of Can, so this was enough to get me going. 

Both designs are pretty close with the Germs being mostly PNP and the Silis being NPN. Comparing the sound of the Germanium units with the Silicon ones it is often said that while the Germs sound raspy, warm and sweet, the Silicons are brighter, edgy and have more gain. Well....from my builds....this statement is....TRUE!

The original 1966 Arbiter Face - Germanium

On my Fuzz quest I really couldn't imagine the journey without understanding the differences between the two FF versions and there was no other way than building the two. After I finished the Germanium Fulltone version I started to drown with info on the Silicon versions: Fulltone, Analog Man, Dunlop, Runoffgroove, GGG you name it. I looked through dozens of schematics and breadboarded some of them. I even looked at the German Schaller Fuzz (FF variant) after reading that Michael Karoli (CAN) used one. Actually, the first fuzz I ever built was the Runoffgroove SiliFace II and I loved it for some months. That was what got me interested in fuzz pedals in the first place, My Fuzz quest started because one fuzz was not enough to get the range of buzz tones I was after.

The 1970 Dallas Arbiter Fuzz Face - Silicon

Due to the fact that the Fuzz Face design is tolerant to part values many versions have been issued over the years and the amount of Fuzz Face versions became quite vast (just like it happened with the Big Muffs or the Tube Screamers). The design is so simple that small part changes resulted in some sonical change. After all the entire unit incorporates 4 resistors, 3 caps, 2 transistors, 2 pots and 1 switch. That's it!

4 resistors, 3 capacitors, 2 transistors, 2 potentiometers

The sound I was aiming for was that of Gilmour playing the Time solo on the album version of the Dark Side. I started out with the GGG early 70's Boutique NPN Fuzz Face after my success with the GGG 60's version. I liked the PRE GAIN knob and the circuit seemed pretty good, but something was missing. I didn't box the circuit and it stayed on the shelf for some time. I built a few other Fuzz pedals and when I thought I understood more about what I wanted I revisited the circuit. This time I modified the circuit based on the Axis Face version by Phillip Bryant modified by Brett Robinson. 

Gilmour's early 70's rig

I did a lot of testing using Hi-Watt amp emulations, tweaked many of the parts in this little circuit, changed trannies and used several guitars. Surprisingly, I ended up using 2N2369 (hfe=70-90) for Q1 and BC109 for Q2 (hfe=200). The BC108C I had (hfe around 400-550) seemed to be too pumped up for my taste. I settled on a 50kA pot for the PRE GAIN and a 100kA for the VOLUME. 220n cap for the input and 30p cap on the bridge for lo-pass filtering. I replaced the CONTOUR pot with a 470R resistor and kept the 22uF Fuzz cap. I kept the reverse polarity protection and cut off the strange feedback diode bridge which didn't seem to affect the sound. Biasing Q2 I got 4.5V with resistance being about 3k3 so that's about 4k3 total Q2 bias. It's funny that this fuzz is currently my most tweaked fuzz circuit to date. Only a few parts but so much experimentation. Other fuzz circuits you get the schematic, the parts, breadboard and maybe test a few transistors, bias them and that's it. Along with the early Tone Benders and the Maestro Fuzz Tone which are more complex it's one of the toughest, considering its architecture.

Luckily, somebody at work who knows I am always on the lookout for metallic enclosures, gave me this great candy box. I couldn't have asked for a better design with those pink pigs on a round enclosure making it suitable for a Fuzz Face and for a Pink Floyd related sound, so I jigsawed it to the right height, called it Pink Face, mixed my glass paint bottles and came up with a magical pinkish tone... Perfect!

The sound is well worth the effort. It's not as warm or sweet as the Germanium version but it does give you the Time solo style. Bright when the FUZZ pot reaches max. The PRE-GAIN gets you that rolled off effect for cool rhythm chords and sparkly clean chops. Using a treble booster in front enables you to get great tones with the FUZZ knob below max. I also tested it with a Wah in front and no buffer was needed. Definitely a must build on my fuzz journey towards a better future.

If you want to learn more about the the topology of the fuzz face there is no better place than R.G. Keen's article: The Technology of the Fuzz Face. It helped me a lot in choosing the right part values and testing transistors both in my Germanium unit and this recent Silicon unit. It is really the Fuzz Face Bible, highly recommended and insightful. 

The schematic I drew up in Chrome Circuit Lab is shown here for reference but feel free to use it, tweak it or twist it. I will update it if I decide to change it. The feedback diode did not really do anything so I left it as in the Fulltone version.

Hope you get to enjoy it! You can also have a blast using Mark's vero layout on Tagboardeffects.blogspot,com

There is a lot of Fuzz Face info all over the web, here are some more recommended pages for extended reading on this matter:

• http://effectslounge.com/blog/more-history-fuzz-dallas-arbiter-fuzz-face
• http://www.custom-sounds.com/Articles/FUZZ-FACE-by-David-Morin, 
• http://fuzzcentral.ssguitar.com/fuzzface.php.
• http://www.analogman.com/fuzzface.htm
• http://www.gilmourish.com/?page_id=73

Shake, Rattle and Roll - The Runoffgroove Tri-Vibe vibrato/phaser/leslie pedal

As I have stated on some previous posts, getting the best fuzz sound or for that matter getting the best sound from any guitar involves more than a few parameters: Picking style, pickups, pedals, amps, mic placement etc. All this is nice and all but sometimes there are more effects involved which really transforms the sound into something else, richer, more psychedelic, more dynamic and new. I am talking about the use of filters, reverbs, phasers, vibrato, tremolo, delay and chorus effects. The first effect I built which was not a distortion pedal was a PAiA Voltage Controlled Filter. Combining the filter with a delay pedal proved to be a super exotic source of psychedelic sounds. I knew I would some day get deeper into modulation effects. As those effects are usually tougher to build I was always intimidated to start one out.

The Swirly Vibes vibrato/phaser/leslie pedal

When I started to get deeper into the Hendrix sound I found the Univibe pedal to be something of a mysterious part of his sound. It is used heavily on Band of Gypsys - Machine Gun, and on Izabella. Later I found out that Gilmour actually used a modified version of the Univibe as the phaser on the opening track Breathe on The Dark Side album (The phaser on the Shine On riff from Wish You was an actual MXR Phase 90). The Uni-vibe was first introduced somewhere in the 60's by Shin-Ei and Vox and was intended to be used as a Leslie simulation. When ROG came out with the Tri-Vibe: a simple enough design aiming to get that sound, I thought it was a good way to get into the business. Even more interesting was the design allowing to combine two modulations together, namely pitch vibrato and phase modulation to get the rotary speaker (Leslie) effect, hence, the Tri-Vibe. I always had a soft spot for Leslie cabinets used in Hammond organs but also on Pianos (Don't Pass Me By - the Beatles), electric guitars (as used by Jethro Tull on Benefit - Guitars, vocals and flutes) and even vocals (John Lennon on Tomorrow Never Knows).

A great page for some info about the Leslie cabinet can be found on:
http://www.theatreorgans.com/hammond/faq/mystery/mystery.html

The ROG design looked very clever and interesting so I built it and stuck it in a modified tin chocolate box. After a few gigs I realized that I needed a stronger enclosure so I reboxed in a regular 1590BB Hammond style box.

ROG Tri-Vibe new enclosure

The circuit has two self explanatory knobs for INTENSITY/DEPH and RATE, and a three position switch to get the SHAKE (vibrato) in the center position, RATTLE (phaser) and ROLL (rotary speaker). I love the rate knob which gives you a wide frequency range from about 0.2 Hz up to 7 Hz or so, that's a few seconds a round to a few rounds a second. Both vibrato and phaser are smooth and gentle and sound pretty damn good. Only drawback of the VIBE effect is that is is really mild and you can really feel it on the high RATE settings. I really wish it was more pronounced. The PHASER swirl effect is milder than the Phase 90 by MXR and it is actually very close to the EHX SMALL STONE which I really like. The Leslie-like whirly effect which is a combination of the VIBE and SWIRL is very good in itself but it only reminds me of the Leslie effect and it, obviously, doesn't have the crunch which accompanies a real Leslie. You can add the extra crunch yourself and get much closer to an actual Leslie sound. Using a fuzz (or better yet the High Tyme Axis/Octavia Fuzz) before the Tri-Vibe on Bass or guitar yielded such a dynamic and rich tone that made me sit one evening playing a single riff over and over dosing off on the guitar. Even the minimum settings on both knobs gives a nice useful hi-pass filtering. I also implemented the suggested mod which gives you the rate indication on the LED which is pretty cool and very useful.

I cannot speak highly enough of this pedal. I can just say that our band's guitarist and me always fight over who will use it on gigs. He actually calls me before each gig to make sure I don't forget to pack it. I guess I might have to build another one. I found a few amazing preset settings which I use very often (in clock numbers for RATE and DEPTH): 9, 3 on Swirl, 11, 1 on Whirl, 2, 2 on Vibe and so on.

The Swirly Vibes patterns

The Tri-vibe is not a Uni-vibe clone and those seeking a Uni-vibe could be disappointing as it doesn't employ the chorus mode which the Uni-vibe is famous for. However as it does have the vibrato mode and 2 swirly/whirly modes, it is a very good replacement and can actually be even more useful than the original. I, therefore, named it Swirly Vibes and painted the enclosure with patterns of waves, swirls and whirls which I really really like. It took me forever to decide on the graphics and after several attempts which failed I went with this great pattern which I got from a designers website.

I discarded the Shake, Rattle and Roll modes naming and just painted a wave a whirl and a swirl to designate the proper switch mode.

This fantastic ROG schematic and layout can be found here. Don't pass on this one. I used the Tri-Vibe name for a while with the old enclosure but after redesigning the enclosure from scratch and putting so much effort into the swirly waves patterns I decided to name it "Swirly Vibes". This is exactly what the pedal does best - swirly vibes.

Bellow are two audio clips demonstrating the Swirly Vibes pedal. One demonstrates the Tri-Vibe with a clean telecaster tone, and the second utilizes the High Tyme Octavia/Axis fuzz in front of the Tri-Vibe. I used all three presets with several settings on each. Just run through the audio clips to hear it's versatility.

The Mixcloud player is slightly less intuitive than the regular Soundcloud because you have to press - "UP NEXT" to get the playlist to show you the tracks, but it is equally well designed.

Tri-Vibe Swirly Vibes Pedal by Doron Barness on Mixcloud

The Fluffy Fuzz Cake

The Big Muff Pi (~3.14) was the first major fuzz pedal by the NY based company - Electro-Harmonix (EHX). The legend says that the first units were brought in 1969 to Manny's Music Store on 48th Street, NY, and a week or so later Hendrix picked one up. The circuit was aimed to recreate some of the fuzz tones conceived by Hendrix using a more complicated design than that of most fuzzes from those days. It was supposed to do everything the FuzzFace did with some extra features and a nicer sustain.

Over the years, a lot of Big Muff variants appeared, each with it's own characteristics and subtleties. Some due to part changes by EHX and some by the fact the the company went out of business and other manufacturers issued they're own versions. Gilmour switched from the Silicon FuzzFace to a BigMuff Pi somewhere around 1977. All the solo guitar work on Animals and The Wall incorporates a Big Muff. Santana also used this unit during the mid 70's. During the late 80's and early 90's the vintage Big Muffs and other variants, most notably the Russian Sovtek version, were a big part of the grungy alternative sound of the bands which defined the genre like Sonic Youth, Smashing Pumpkins and Nirvana. Mudhoney went as far as naming their Ep "Superfuzz Bigmuff". Having so much legacy and history around this pedal, I had to try it but I couldn't decide which version to go for. It was actually the first fuzz pedal that was named a distortion pedal.

The original circuit I built was taken from the GeneralGuitarGadgets site shown here. Some of the changes made by EHX over the years as well as the designs made by other manufacturers can be found on the same website here. Although they rely on the idea of cascaded gain stages with diode clipping on each stage, they all sound a little different (tonestack, caps, trannies etc.).

The most gratifying unit I built around the Big Muff concept was the ROG 22/7. The ROG team did it again with a super cool design to get the entire pie in one bite. The name comes from the number pi, but the sound is the fluffy triangular pie which we love so much (How did EHX ever get a way with such a nasty name for a pedal?). The most notable thing about the pedal is that it is based around a CD4049UB IC which makes up the gain stages, and the fact that you have 3 variants in a single circuit!!! the original classic sound, the flatter Russian Sovtek sound and the scooped Ram's Head version. What a great pedal. Every guitarist I played with loved it. It's sustain is super smooth and you can get a very heavy Billy Corgan/Thurston Moore sound easily. Very very cool. The circuit can be found here. A lot of info on this pedal can be found on the Pistones website.

I admit that I did not intend to dwelve so deep into Big Muff territory when I first started my quest for the ultimate fuzz, but this is a great versatile fuzz unit and could easily satisfy grunge heads and fuzz heads alike.

Tyme for some High Octave Fuzz

Ever since I have been reading and listening to various type fuzz circuits I was always intimidated a bit to build  an octave fuzz, mainly 'cause I don't really care to much for octave pedals. Sure they are interesting pedals to play with and toy around, and some great guitarists have made some great solos using octavers, both up and down, but it's not what I am usually after in my sound. Anyway what I'm trying to say is...boy...was I wrong.

My first attempt at an Octave fuzz pedal was made by tampering with a Jordan BossTone fuzz which had a pot for battery starving effect (a tip from freestompboxes.com). This yielded an Octave Down effect with a lot of buzzing which sounds a bit like the Motorcycle effect done by Brian May. Pretty cool, hu? but I'll post this one later on.

Then I read an interesting story about Hendrix playing the Purple Haze solo through the mysterious Octavia fuzz made by Roger Mayer. It is told that one of these pedals was stolen, and reappeared after Hendrix's death under the Tycobrahe brand. After listening to more tracks allegedly played through this Octavia pedal I realized that this pedal has a lot to do with what I call the Hendrix sound. Although he used the Maestro FuzzTone and various Fuzz Faces quite a bit, he also used a pedal called the Axis Fuzz and the Octavia. Both of these pedals sound fantastic and very versatile so I could n't sit still, of course, knowing that they are both in one medium difficulty circuit.

Wondering the web for circuits I ended up using the GGG circuit which had some new features like negative ground, PREGAIN knob, polarity protection and also featured the Octave On/Off switch, so that it's actually two pedals in one. The first part of the circuit is actually the highly acclaimed Roger Mayer Axis Fuzz and the second part is the Octave-up which used a coil transformer for frequency conversion. Mind you that the later Roger Mayer Octave Fuzz is a different circuit and does not have the transformer for the octave up thing. From what I understand the original pedal did include a transformer for the frequency doubling.

I ordered some parts from SmallBear and Mammoth, breadboarded the sucker and when I saw that it was all good I boxed it and called the pedal the "High Tyme" fuzz and for a very good reason. As soon as I plugged my guitar in I was back in Psychedelic Ladyland. This pedal is so sweet you wanna eat it. The Axis-fuzz circuit is musical, smooth and rich. It actually sounds much better and more defined than your usual Fuzz Face, and more vintage sounding than any BigMuff if you wanna go 60's. You can play around with the INTENSITY knob but it really sounds good anywhere on the clock. Once you engage the Octave everything goes berserk. You can roll off the guitar knob or use the PREGAIN and as you roll it down you can get a cleaner octave which can sound very interesting on the high notes on the neck pickup. What I love even more is the sound of the pedal on Bass. I spent an entire night playing bass using the pedal with a phaser right after it. The sound was so inspiring that I couldn't stop. It can get really nasty and quirky on the higher settings. Btw, for the Octave on/off switch just cut the transformer's primary channel diode from the ground and hook it on a SPST switch. Yes, it's that simple as shown here.

I don't know if this circuit is the exact circuit Hendrix played through but it is definitely out there. It's probably the closest I got so far to really reaching my goal on this quest. Lately I've heard of a band called T2 which released one album "It'll All Work Out In Boomland" in 1970 and boom they split. On the new CD release there is a bonus track called "Questions and Answers". 17 years old guitarist, Keith Cross, plays 3 amazing solos on this track which climb up the fuzzy scale throughout the track. The fuzz he uses has got to be the Octave Fuzz 'cause no other fuzz sounds quite like it. you can listen to it using this link. You won't regret it. If you wanna build it.and you need the schematic...here is the magical recipe for this Psycho potion.

  

The Rocking Marshall World

The Almighty Thor

If the Fender amps are the trademark sound of the classic American Blues, Rock'n Roll and Country, the Marshall amps are the definitive sound of Rock. Jim Marshall past away a few days ago and it's a good point to bring out another great pedal from Runoffgroove named "THOR". This design aims and succeeds in recreating that vintage Marshall amp character, clean or driven.

This circuit design uses again the Tubes-to-FETs process first suggested by Doug Hammond and later enhanced by the wonderful ROG team. This pedal is inspired by early designs of the JTM and Super Lead Marshall amps. These amps showed up in the UK in the mid 60's after Jim and his son Terry (JTM) tried to design a cheaper version of the classic american Fender Bassman using military American tubes.

Thor's Hammer on

The characteristic sound of these classic Marshall amps, which is the original Plexi sound, is what this pedal is all about. You can get close to the signature sound of Hendrix, Richie Blackmore, Pete Townsend, Angus Young, early Clapton, Steve Hackett, Billy Corgan, Dave Navarro, John Fogerty, Slash, Mick Ronson and the list goes on forever. You have a BRIGHT switch which gives you extra sparkle and a BOTTOM switch giving you more body emulating a large 12X4 Marshall cabinet. The GAIN knob goes from beautiful clean to hard overdriven blues rock crunch which is great for chords or soloing. I have used this pedal for a while now in the studio and live and it's my #1 go-to pedal with a Telecaster. You can get the schematic here.

Below are two clips of a few of the sounds which the Thor has to offer. I played the first clip with HB on a HiWatt amp emulation preset and the second on a Tele with single coils. The tracks are quite lengthy but you can just wonder around and hear what it is all about. As you will hear, The Marshall is the definition of rock guitar sound from Classic Rock, Country Blues Rock, Acid Rock, British Invasion Rock and Prog Rock to Punk Rock, Grunge, Alternative and Heavy Metal, This is the sound.

Hot Cloudcasts featuring Thor Demo by K. Zustang on Mixcloud

Single Coils Tele - Thor - HiWatt amp emulation by Doron Barness on Mixcloud

The Germanium Fuzz Face

Once I had a few Germanium Tranny lying around and I knew how to measure them properly for leakage and gain I continued my quest for the perfect fuzz with the most famous fuzz in the world of Rock and Blues. My first fuzz ever was the Runoffgroove Silicon Fuzz Face which I built a few years ago. This time I'm going all the way back to 1968

This was, of course, Fuzz Face, issued around 1966 by Dallas Arbiter in the UK. The original Face was built with 2 Germanium trannys which were replaced in the early 70's with Silicon ones.

Hendrix, Muddy Waters and Gilmour used the Ge version and I thought I'd give it a go as it is such a simple design. I got a round candy box from a friend at work and finally decided to go with the FullTone '69 schematic which appears on GeneralGuitarGadgets. It's not the finest enclosure but....its round just like the Face and I kept the name - '69. 

This version implements BIAS and BODY controls for more tone control, very similar to the FullTone version and you can really play a lot with the sound. The AC128 Ge Trannys are supposed to be less stable and temperature dependent but I don't  feel any weird behavior from the unit on stage or at home. All I heard was great singing quality which really makes your guitar sound like a square wave synth. Using the BIAS knob or the guitar volume knob gives you that clean edgy sparkling Hendrix sound which is heard so often when he plays chords. I always thought this was an amp thing. Compared to a Silicon Fuzz Face it is deeper and bassier. anyway its singing quality and voicing is great. quite an amazing sound for such a simple design. Most of the time I find myself having the FUZZ knob cranked all the way up.  You can look up the schematic on the GeneralGuitarGadgets website or get it here.