Sunday, December 11, 2011

Dyna Comp Compressor

The MXR Dyna Comp is one of the best compressors out there. It is generally regarded as the compressor against which other compressors are compaired.

However, they have a double sided circuit board. This makes repairs a bit tricky. Desoldering in particular becomes a cumbersome task. Too much heat can make a pad lift off from the board.

The pedal below came into the shop with some intermittent problems after a previous potentiometer replacement. The pedal would cut out when the sensitivity knob was touched or manipulated. I found that the pads connecting the pot were starting to come loose. The solution was to make a solid electrical connection by putting in some jumper wires. These connected the lugs of the pot to the next component that the pot was supposed to be connected to. Some circuit tracing was required to figure out where to connect to.

Monday, September 26, 2011

Route 66

Whoa this pedal is totally cool! What a great idea to combine a TS-808-like distortion with compression in one pedal. The housing is all totally old school pressed metal. The inside circuit is most beatious. Nice circuit layout, wide and roamy with plenty of elbow room.

This unit had a fried resistor due to some abusive power supplies. The resistor was fried beyond all recognition (FUBAR). No way to tell what value it was. Some circuit tracing in the power supply section was required to determine an appropriate replacement value. The pedal is now on it's second life!!

Thursday, August 11, 2011

Replacing pots in an Arion Stereo Chorus

The Arion and Roctek pedals are notorious for failures in the potentiometers. The small cheap pots have extra-long shafts and are mounted directly onto the PCB. The long shafts provide more leverage, increasing the chances of something breaking.

It's possible to replace these pots in some cases. With the Arion Stereo Flanger there isn't quite enough room to replace all 4 pots with standard 16mm Alpha pots. But you *can* replace the two outside pots.

An example is shown below. The outside pots have been replaced with Alpha 16mm pots. The pots are now mounted on the pedal housing. The original Arion knobs wouldn't fit on the Alpha shaft. Some filing, or drilling out, is required so that the knob can go onto the new shaft. The plastic bar that goes across the pot shafts inside the pedal housing was also cut so that it only went across the two original shafts.

This pedal lost it's original battery cover. Generic replacements are available directly from Arion.




Friday, July 01, 2011

PSA/ACA switch for BOSS HM-2

Here's a Boss HM-2 with a switch that selects between a Boss PSA or ACA power supply.




When you use a PSA power supply and put the switch in the PSA position then the pedal works great. When you use a PSA power supply and put the switch in the ACA position, like the stock circuit, then the pedal is starved for voltage. The circuit isn't quite getting enough voltage to work like it was designed to. It sounds very lo-fi and ratty. In a mostly bad sort of way.

One of my earlier posts talked about the ACA to PSA mod. This pedal has a switch to select the option of engaging the mod (PSA mode) or going back to stock (ACA mode).

Friday, June 17, 2011

Seeing Eye-Dog Mod

The Boss SD-1 is like a DS-1 on steroids. The distortion is more aggressive.

I tried several mods on this SD-1 until I finally found some that I liked. It has a Seeing Eye-Dog mod on the inside. There is a new toggle switch for the tone. In one position a filter cap is lifted out. This gives the pedal a bright loud sound, great for punk or No Wave. Putting the switch in the other position gives a darker bassier sound, like a neck pick up sound.

Of course the boring little red LED indicator has been swapped out for a giant bright orange LED.

Here's the inside of the pedal showing the filter cap and toggle switch.



Here's a photo of the modded pedal with the toggle switch for the tone.

Monday, May 23, 2011

Fish Fights at the Shipwreck

Got to check out the new aquarium at the Shipwreck Tavern before the show on May 21, 2011. At 150 gallons this big tank is noticeable.

It's a fresh water aquarium. There was a catfish, a couple of boisterous crayfish and a few other fish (gouramis?). The show went well - the Shipwreck is always a good place to play.

Wednesday, May 18, 2011

Fremont White Rabbit

Brad Yaeger and the Country Gentlemen had a great show last night at the recently opened Fremont White Rabbit. This is "The Bar Formerly Known as TosT".

The industrial atmosphere has been transformed into a dark cozy "rabbit hole". Dark interior with books and candles on the wall and some blue mood lighting.

Performers will notice great improvements. For starters there is now a real green room, complete with chilled bottled water. Whoa! A first for the Country Gentlemen! Huge monitors are in the front of the stage. A burly snake is on stage left. Very professional looking. The back of the stage is adorned by a trippy commissioned painting that gives the illusion of a giant rabbit hole.

Wednesday, April 20, 2011

Vintage DOD FX55-B Supra Distortion

The FX55 used to be called the "Super Distortion". Until some good lawyers from a pickup manufacturer started sending persuasive letters to DOD and they had to change the name.

Here are a couple of red rocking vintage DOD FX55-B pedals. The pedal on the left is probably from 1994. The pedal on the right is probably from 1988.

The left pedal has the "bar" style model name while the right has "box" style. The logo is "italics" on the left and is "shaded relief" on the right. Footswitch plate is blank on the left and has a "DOD" on the right.



Below shows some differences in the bottom plates. Smooth for the left and serrated (WICKED!!) on the right.



And on the inside? Not much difference. The PCB layout hasn't changed between models. The biggest difference seems to be a transition from yellow to greenie caps.



Both of these came into the repair shop with switching problems. Here's the internal switch on the 80's model.




Information on the dates of these red rockers came from the
America's Pedal web site.

Wednesday, March 30, 2011

Rehousing a Rocktek Flanger

Not really a huge fan of plastic enclosures, I decided to rehouse a worthy Rocktek Flanger in the enclosure of an MXR Stereo Chorus (with a dead Reticon chip).

I removed the Flanger from the enclosure. Q6 was removed and jumpered to put the flanger in an "always on" mode. D3 was also removed. True bypass switching will be used on this project.



After verifying the "always on" mod I then removed the in/out jacks and all the pots. I purchased new replacement pots and put those in the MXR enclosure. I used the old jacks from the MXR chorus. I needed to drill holes for the on/off LED, the LFO rate indicator LED and the Feedback pot.



Usually a stereo input jack is used to switch a connection to the power supply (ie, turn on the box). None of the MXR jacks were stereo. I installed a SPST on/off switch in the hole for the old AC power connection. The wires for the on/off switch were connected to the input jack ground connections on the flanger PCB.

The flanger also needed some ground jumpers on the old pot connections.



Another beautious mod was to decrease the value of the feedback resistor. The pedal can now go into howling self oscillations when the feedback knob is cranked! My dog loves these sounds so much that he howls back at the pedal.



More info:
Pedal Area
Wikipedia entry for flanging

Tuesday, March 15, 2011

Seeing Eye Dog

Here's a DS-1 with the Seeing Eye Dog mod and a switch to go into Ultra Underdog mode. The little LED lights up when you play your guitar. Cool! Wink, wink! The on/off indicator LED has been replaced with a big bright blue LED.

Wednesday, March 02, 2011

Big Heavy Ball

The Ernie Ball Volume pedals are extremely heavy duty. These look like they could last forever - with some TLC now and then.

This 6150 needed to be taken apart and put back together to get it tweaked back into place. I like how it has strings and springs inside. Very old school mechanical. The aluminum and the mechanics make me thing of WWII airplanes.

Thursday, January 27, 2011

Interesting Sounds from the BF-2

Here's a mod that comes from the Brian Wampler book. Putting the cap across a couple of pins on the clock controller gives some big depth on this Boss BF-2 Flanger. Woohoo! More of a bend than a mod.

Decided to not keep this one for now.

Otherwise, I did all of the Wampler mods to clean up the hiss and reduce the "boxy" sound. Then I replaced the op-amps with Burr Brown low noise op amps. Now a sweet sounding "Made in Japan" BF-2.






Time to play around with some of the trimpots!!

Friday, January 07, 2011

ZMD #4 - the Dog Face

Zorro Music Devices #4 is finished.

It's called Dog Face.

It's mean! It's fierce! It'll bite ya!!

It's a Fuzz Face clone. This pedal has provided hours of fun! I've been practicing with this one and haven't used my Tube Screamer or Big Muff for a while.

November Update

A big repair project kept "The Zorro" busy for the month of November.

Many of these pedals were in a flooded basement and had been under water for several hours. OH THE HUMANITY!! They were definitely worth opening up and putting in the time to bring them back to life. The worst was the Tube Screamer. This thing was riddled with rusted components and was sounding really ratty. A lot of replacements got the pedal breathing and back on its feet.

The moral of the story: if your gear is soaked then open it up and let it dry out for a really long time!!! Wait a while before you fire it up again.