Welcome to the Revolution

Hi there, welcome to my blog - La Revolution Deux. It's an odd name - but I like it! Here you will find all the info on my various DIY Guitar effects builds, amplifiers and guitars. Everything from a humble Ibanez tubescreamer to the holiest KLON Overdrive.

You may also find a few effects builds that I am looking to move on - usually in exchange for other effects/gear/cash. You can always check my ebay account to see what I've got up for grabs.

Have fun, enjoy the blog - Fred Briggs :-)

CONTACT ME



Feel free to get in contact with me about anything you see on this blog or with any general questions about guitars, amplifiers and effects, I'll be happy to answer! Just click the button above to email me directly or alternately my email address is fredbriggs2007 [at] googlemail [dot] com

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Friday, 15 January 2016

DEADplate - "five to nine" - Practise and recording amp

If you're looking for a five to nine watt practise and recording amplifier - build this, it sounds great and only uses two valves! It's got a special mosfet based phase splitter design which I've not seen anywhere before - so I'm claiming my design is unique :-)


Build it and leave your comments below.

Tuesday, 30 April 2013

Trainwreck Amplifiers - Express - Liverpool - Rocket

Ken Fischer with his Trainwreck amps
If you're interested in guitar amplifiers and haven't heard of Trainwreck amps then you must be stuck on a desert island. Known for their no frills design, great clean shimmer and screaming lead tones Trainwreck amplifiers were hand made in the 80s and through the 90s by the late Ken Fischer. He was one of the first "boutique" amplifier manufacturers to enter the market and many of his design philosophies, construction techniques and circuit designs are still around in the amplifier market today.

An unbelievable collection of Trainwreck and Vox amplifiers
There are three main Trainwreck designs;
  •  the "Express", a 50W screaming lead machine using 2 EL34 output valves to generate super compressed lead guitar tones.
  • the "Liverpool", a 30W combination of the Express preamp alongside a quad of EL84 output valves to create a slightly mellower version of the Express. Ken designed this one with single coil guitars in mind.
  • the "Rocket", a super fine tuned version of the VOX AC30 Top Boost.
Unfortunately Ken only managed to produce around 100 or so amplifiers before his health deteriorated to the point where he was unable to build - this makes original Trainwrecks rarer than hens teeth (or in fact rarer than original Lovepedal circuit designs ;).


Now, before we go any further and take a look at the actual circuits we should probably have a listen. Here's some demo videos of the Trainwreck amplifiers in action;




So there they are, some pretty decent sounding amplifiers. But we want to know how to build them. There are literally thousands of forum posts and discussion on these amplifiers and a few kind owners of originals have taken pictures of their amps to allow others to attempt to clone there sound. Most of this information is stored on the great Tube Amp Garage Forum (which also covers the much sought after Dumble amplifiers).

A 1989 Trainwreck Express
"Ingrid" Trainwreck Express
Gutshot of Ingrid
Now, first up is the Trainwreck Rocket schematic;



The Trainwreck Liverpool Schematic;



And finally the Trainwreck Express Schematic;



Notice the similarities between the Liverpool and the Express - same preamp circuit different power amp. Also notice how they use that third triode "cold biased" to get some real preamp clipping going in much the same way as the great Marshall JCM800 (2204) does. The Rocket, as you can see, is just the top boost Vox AC30 refined to a single channel.

On their own the circuits are nothing spectacular; the key with these amplifiers is in their construction and tube selection (and transformer selection - the Express uses a custom build output transformer with a 6k6 primary and the Liverpool a, rather odd, 5k2 primary (usually quad el84 amps use an output transformer with a 4k primary winding)) - if you don't get these factors correct then you'll have an amp that sounds all right, but it won't sound like a Trainwreck. But how do you select tubes for Trainwrecks and tweak them to perfection? Well, it's back to reading all those forum posts and filtering out the truth from the myth and being prepared to lay out some serious cash on NOS tubes!

Below are the links for a full BOM (Bill of Materials) and Layout files for each of the Trainwreck amps.

For a full schematic, BOM and layout of the Express check out this Amp Garage topic; http://ampgarage.com/forum/viewtopic.php?t=5691

For the Liverpool check out this topic; http://ampgarage.com/forum/viewtopic.php?t=5677

And for the full Trainwreck Rocket documents have a look here; http://ampgarage.com/forum/viewtopic.php?t=5684

Tuesday, 2 April 2013

Vemuram - Jan Ray Overdrive


So, if you've heard of the Japanese pedal company Vemuram you've probably heard about this: Vemuram Jan Ray = Timmy Clone. It's an attractive pedal - nice brass enclosure, vintage looking knobs. Check it out in action here against the Timmy (yes, there are slight differences - the treble control has a different range and the OPAMP chip is different but the circuit structure is exactly the same.);


Now, the Timmy (the original which is made by Paul C and has been since 1997) has been cloned several times in the past by many different manufacturers. Off the top of my head there's the Danelectro Cool Cat Transparent Overdrive and the Lovepedal OD11.

Well we have mmolteratx to thank for discovering this latest example of boutiquer cloning. He picked one up and gutted it before tracing it out and providing a schematic for us;

Vemuram Jan Ray Guts
Vemuram Jan Ray Guts
And here's the schematic he drew up;


Yeah, it's a Timmy with a slightly altered treble control. Here's an explanation from mmolteratx;

"No, it's entirely in the different treble control. The bass response is exactly the same, all the trimmer does is vary the effective value of R4, which sets the gain of the stage. The treble control on the Jan Ray lops off everything above 2.8kHz at -6dB/decade at max. The Timmy's control at minimum does the same, but at 10.6kHz. Just use the Timmy's control in a different range and you've got a Jan Ray."

So, there you have it, nothing new and yet another clone. For more information, and a great layout from IVIark (of tagboardeffects.blogspot.com) on the Vermuram Jan Ray Overdrive visit this; http://freestompboxes.org/viewtopic.php?f=7&t=21934

Thursday, 28 March 2013

Bearfoot / BJF - Baby Pink Booster


I like collecting BJFe designs, I like their simplicity and the fact that they sound really good. Here's one of Bjorn's latest offerings - the Baby Pink Booster.

Here's the description from the Bearfoot FX website;

"+15 dbs of clean guitar friendly boost and a tasty buffer ... Deluxify your drives ! If you've seen the very expensive BJFe Honey Bee and Baby Blue and Emerald Green 'Deluxes' .... this is whats in there besides the drive circuit ---- the BPB is the buffer and the boost for those ---- so put the BPB at the end of your dirt section and 'Deluxe' them all. 8-18v for more headroom and clarity if needed"

Gutshot of the Bearfoot Baby Pink Booster
And, as usual, a YouTube clip of the offending pedal "in action" alongside some late 80s haircuts;


And here's the schematic provided by mmolteratx;


There you go, a simple jfet setup that runs at unity gain without the boost pot wiper connected to ground and boosts when the effect is engaged. For most fun - run this thing from 18 volts for extra gain and fun. You'll need to select the jfet as to get it biased correctly, go for one that gives you around 4.5v on the drain (or just one you like the sound of).

For more info and a few vero layouts check out this thread at freestompboxes.org; http://freestompboxes.org/viewtopic.php?f=7&t=22020

Monday, 23 July 2012

Wampler - Ecstasy / Euphoria Overdrive


The Wampler Ecstasy has recently been renamed the "Euphoria", for what reasons I'm unsure but it could be to do with a few not-so-positive forum topics popping up on google when you search for Wampler Ecstasy! I thought I'd already covered this one but a quick trip over to IVIark's tagboardeffects.blogspot.com reminded me that I haven't! The general circuit topology has been known for a while after Brian Wampler kindly got stuck in and posted a few hints over at the freestompboxes.org forum;

"Here's the thinking along the design of the ecstasy. The idea was to boost the bass to fuzz up the bottom end a bit, yet retain soft clipping. So there's a pot to a big cap (nfb to ground), variable low pass filter as a tone control, simple gain boost opamp stage after this. [The] switch adds in diodes to 4.5v ref (IIRC!), soft clipping only, or no diodes which is all opamp clipping. Simple design, but works and sounds great."

Gutshot of the Wampler Ecstasy Overdrive
So let's have a read of the description of the Ecstasy / Euphoria from the Wampler website;

"When Brian created the circuit that would eventually become the Euphoria, he was working on creating a pedal that would go from clean tones to distorted tones while adding a bit of warmth. He wanted something for himself that would be dynamic, have a great sounding “gritty” tone to it yet be able to respond to the volume knob like a tube amp. Everything about Brian is in the dynamics of sound and if a pedal can't work with him dynamically, then he just can't use it.

The Euphoria is his take on that elusive tone and feel made famous by Dumble Amplifiers - smooth creaminess yet crunchy when you need it to be, yet the tonality is much more transparent than other “dumble sounding" pedals. Very responsive tone controls that interact with the pedal - they don't just “color” the sound. The controls actually affect the response and feel of the pedal, just like a great tube amp.

If you love the sound of your clean tone, and just wish you could have more “hair” on the note... a little bit of grit without any change in tonality, the Euphoria will do that with ease. PLUS it's extremely flexible... with the toggle switch in the down position you'll get a hint of fuzz along with the overdrive, it's reminiscent of the tones that "Eric Johnson" may use. With the toggle in the up position the tonality is super smooth, creamy yet crunchy when you dig into the strings.

This is reminiscent to the famous “Dumble” tone, though it's really much, much more than that. In the center position, the toggle will give you tons of crunch, or roll the gain back a bit and push the volume up and you have a superior clean boost with a 2 band EQ that's extremely transparent, but variable so you can actually turn it into an awesome treble booster just by cranking up the treble and turning the bass down."

Here's a ProGuitarShop demo video of the Ecstasy / Euphoria in action;


Now we've heard it lets see the reversed schematic;


Note that the schematic is a screen grab from modelling software - you don't need the three seperate voltage dividers which provide 4.5v, a single voltage divider will do with all of the points that need connecting to 4.5v pointed there. the 12.5k/12.5k resistors in the filter at the rear of the circuit are in fact a 25k pot with it's middle lug connected to the 22nF cap. The opamp (as seen in the gutshot above) is a JRC4580D.

So looking at the circuit layout it's pretty simple - tubescreamer/voodoo labs overdrive hybrid with a treble roll off control. The switching goes between soft/none/hard clipping options and the bass control is the same bass control as is seen on PaulC's Timmy Overdrive.

For a vero layout check out tagboardeffects.blogspot.com; http://tagboardeffects.blogspot.co.uk/2012/07/wampler-ecstasy.html

For more info here's the freestompboxes.org forum topic; http://freestompboxes.org/viewtopic.php?f=7&t=13611&hilit=wampler+ecstasy