Vintage EHX Clone Theory overhaul



The EHX Clone Theory chorus and vibrato pedal is one of those pedals which we rarely see but those who use it will swear by it. The setup of the pedal is very similar to a vintage Deluxe Electric Mistress and can share some of the same mods. This one specifically was converted to true bypass, had an LED installed to indicate when the pedal is active, had an upgraded input buffer, and a boost at the output to increase the overall volume from the pedal.

One other change that we made (and the reason for this blog post) was to mention that this pedal can be converted from the 110V AC plug to a 24V DC power jack as used by the Deluxe Electric Mistress. This is a great option for those of us with pedal power supplies which do not have an auxiliary power output. As always I advise upgrading the aging electrolytic power filter caps to ensure the pedal will continue to function properly.

Posted in Modifications | Leave a comment

Boss DF-2 Super Distortion & Feedbacker overhaul w/ auxiliary output

This Boss DF-2 was sent in by a client who loved the quirky feedback this pedal is capable of but wanted to make it more versatile and musical. For those of you who haven’t used one of these pedals, well…. it’s unique. You turn on the pedal and you get a Boss DS-1 style distortion and if you hold down the footswitch the pedal will sample your guitar at the input and generate a “feedback” pitch based on that note. It’s cheesy but can be fun when used properly.

The first part of this mod was to remove the distortion from the guitar signal. The idea is that most people have their own overdrive/distortion and wouldn’t want to sound like a Boss DS-1. Another added benefit is that all of the controls (Level, Tone, Distortion) that were once shared between the guitar signal and the feedback signal are now dedicated to just the feedback. You can sample a clean guitar and generate a feedback signal with complete control over volume, brightness, and gain.  That’s part of the standard Overhaul and more info and a video can be found on the FXdoctor DF-2 page.

After that the pedal had an additional output jack installed to send just the dedicated Feedback tone without any guitar signal. This is a great option for running the feedback through separate effects, loopers, delays, and into another amp. If that setup is too complicated another option is to use the left toggle switch to kill the dry guitar signal when the pedal is activated. This allows you to just have the feedback pitch when the pedal is on; great for layering tones in noise bands and creating huge loops. The other toggle switch switches off the seasick-vibrato effect in the feedback.

Overall this was a challenging project just due to space constraints. If you’ve never popped the back off of a DF-2 it has a large circuit board filled with through hole components which takes up more room than something like the surface mount components in newer pedals. Fitting in two toggles, an extra 1/4″ jack, and additional switching/output circuitry required some careful planning and the sacrifice of the battery compartment.



Posted in Custom Shop, Modifications | Leave a comment

Pro Co Rat installed in an EHX Big Muff

For years we’ve had people send various Big Muff pedals for rehousing into a smaller casing. The circuit board isn’t nearly as large as the casing that it ships in (specifically in the USA reissue) so it’s a great candidate for space savings. Just recently we had a customer request that a Rat be installed inside of the Big Muff to save space. We also installed a Clean Volume knob to each circuit to allow the original signal to be mixed in with the distortion. The end result is two independent distortion circuits in one casing to save space and help simplify a pedalboard.

Posted in Custom Shop, Favorites, Rehousings | 1 Comment

EHX Deluxe Electric Mistress Rehousing

The Deluxe Electric Mistress is the flanger that we see in here the most. It’s a great sounding flanger but there are so many reasons that it’s not friendly for a gigging musician. We’re offering a standard rehousing service which addresses common problems and keeps the cost lower than doing a custom rehousing each time.

First we’ll take the guts and put them into the 4.5″ x 5.5″ casing that you see above. The jacks are changed to a more conventional layout. We rewire the pedal for true bypass and add a status LED as well. If your pedal is an older model which has a 3-prong cord then we’ll convert it to accept a 24V 2.5mm DC power supply as used in the current models. We found that the best way to rehouse this pedal involves wiring the Color knob in reverse (clockwise is minimum; counterclockwise is max). This is done intentionally and is a result of moving the pots which also support the weight of the PCB. The end result of the changes is a pedal that sounds 100% as it did from the factory but in a smaller, pedalboard-friendly package.

Other add-ons include installing a volume boost circuit to bring the volume up to unity gain or a simple Enhance mod which brings out the highs and lows in order to compensate for the volume drop.

Check out for current pricing and a video to demonstrate the Enhance mod.

Posted in Rehousings | Leave a comment

Vintage Small Stone Rehousing

This Small Stone has had quite a history of tinkering and modifications. When it arrived it had broken wires and was literally falling apart. We decided to take it on as a complete rebuild. Every single wire was removed from the circuit board and all modifications were removed so we had a reliable starting point for the restoration. Some of the mods include:

  • Complete rehousing in a 3.5″ x 4.5″ casing with new jacks and switches
  • True bypass with an LED
  • Color switch converted to a stompswitch; the LED turn blue when in Color mode, green when in regular mode, and is off when bypassed
  • Mix and Volume knobs installed
  • Aging capacitors replaced and LFO ticking removed
  • Boss style DC adapter jack installed

Overall this pedal is awesome! These vintage Small Stones just sound amazing and with the new modifications it should provide years of reliable operation.=

Posted in Favorites, Rehousings | Leave a comment

Mu-Tron III overload!

We’ve seen all sorts of Mu-Tron III variations throughout the past year. Some early models that don’t have a DC jack, some late models that didn’t have an option for batteries, some bare circuit boards in need of rehousing. These pedals really do sound amazing although their large footprint and heavy casing can be annoying for gigging musicians. My personal favorite mods so far:

1. Install a charge pump so the pedal can operate off of a single 9V battery.

2. Remove the Gain knob and install a Filter Sensitivity knob. The Gain knob adjusts the volume of the pedal both while on and when bypassed which can be a nightmare for keeping a consistent volume throughout your signal chain. Bypassing the Gain knob would set the volume to unity gain; Installing a sensitivity knob would adjust how wide the filter opens without changing the overall volume of the effect.

More info on our Mu-Tron mods can be found on the main site.

Posted in Favorites | Leave a comment

Musitronics Mu-Tron III rehousing

The Mu-Tron III has a legacy of being one of the best envelope filters ever made. Some of the big names that made this pedal so popular include Stevie Wonder, Bootsy Collins, and Jerry Garcia. The pedal sounds excellent but in it’s original state can be a disaster for a gigging musician. The original has a massive enclosure (5″ x 8.75″) and is very heavy with a steel base. It runs on a special dual polarity power supply which makes it not very pedalboard friendly. From the factory it also has a switch to turn off the power which is just one more thing to wear out or become accidentally (unknowingly) switched off.

This pedal functions 100% the same as the original but in a smaller package and a standard 9V adapter jack.

Knobs from left to right: Gain, Peak, Mode

Switches: Drive (left), Range (right)

And a before shot of the original Musitronics 0601 circuit board found inside:

Posted in Rehousings | Leave a comment

Boss CE-2 Restoration & Rehousing

This week we received two Boss CE-2 Chorus pedals in different states of disrepair. The first that arrived is pictured above in the left panel. It arrived exactly like that: missing parts, disassembled, and painted black. Although the original paint was beat to hell it still looks better than the faded black paint. Surprisingly the circuit board was 100% original so the restoration was mostly tracking down appropriate replacement hardware.

The original pedal was designed to run on Boss’s ACA120 adapter. This is the unregulated 9V adapter which they’ve long phased out and replaced with the PSA120 9V regulated adapter. Ibanez, Danelectro, DOD, Digitech, Voodoo Lab, Boss, and almost every other current pedal manufacturer uses a regulated 9V power supply. If you hook up a stock CE-2 to a regulated 9V adapter you’ll likely be providing slightly less voltage than intended and– while it will in no way damage your pedal– will have a dimmer LED. We modify the CE-2 and any other pedal designed for the Boss ACA120 adapter to run on a modern powder supply. This mod is also built into the cost of our Overhaul modification.

Speaking of the Overhaul modification, it also includes sonic and aesthetic upgrades. We replace key capacitors in the audio path including electrolytics with Panasonic metal film caps. Also replaced is the main audio op-amp for more headroom and a cleaner tone. Last we install a blue LED and set it to pulse to the rate of the chorus when activated. This makes a great pedal even better!

Here is another CE-2 we received as nothing more than a circuit board. The casing, jacks, footswitch, knobs, and pots are all replacements. Converted to true bypass and installed a large LED for better visibility. All fun stuff and these two exact pedals are currently (as of 9/25/2012) are listed on eBay! I’d love to see someone commission a true stereo output for their CE-2..

Posted in Modifications, Rehousings | Leave a comment

Boss PD-1 Rocker Distortion- Power Conversion

The Boss PD-1 is a distortion pedal with a treadle to adjust the amount of gain. At the toe you have a “warp” switch which is just a high gain momentary switch. It’s very basic and contrary to popular belief it bears no resemblance with the Boss DS-1. This pedal is unique because it’s one of the only Boss compact stompboxes I’ve seen that was designed to run on a 9V adapter or two C cell batteries. The current draw is under 10mA so large batteries are absolutely not necessary for the pedal to function. It uses that large black box (shown below) to increase the 3V from the battery to 10V. A quick conversion allows this pedal to be run on 9V PSA120 adapters (Boss’s current standard) or a 9V battery. Some shots of the internals before and then a shot of the 9V battery holder:

Posted in Modifications | Leave a comment

Boss Chorus modifications

I’ve always noticed that the Boss CE-5 and CH-1 chorus pedals sounded unnatural. The pulsing effect wasn’t smooth but seemed to pulse like an engine struggling up a steep incline. The effect is even more noticeable once the pedal is modified with our Vibrato mod. The LFO is the part of the circuit that creates the pulsing cycle; when you turn up the Rate knob you’re directly changing the timing of the LFO. Above is a picture of the waveshape at the output of the LFO showing why the effect has an unnatural pulsing sound. You can see in the bottom half of the image how a symmetrical wave form will give a more natural sound and smooths out the stuttering. Video clips will be posted in the near future.

Posted in Modifications, Prototype | Leave a comment