1966 Gibson EB-2D “Triple Bypass” Modification


For those brave souls who wish to go fishing in their F-holes, I present to you a case study in implementing the fabled EB2 choke-bypass modification.  This was my attempt at it, and I was extremely happy with the outcome – especially since no irreversible modification to the bass was required.   What is this […]

1995 Rickenbacker 4003s/8 Structural Repair


In December 2012, I purchased a Rickenbacker 4003s/8 8-string bass project from Ishibashi Music in Japan.  The bass had been heavily discounted due to a structural issue that had rendered it unplayable.  If I recall correctly, their website listing stated something to the effect of: “major faulting, we do not recommend this bass” :) I […]

Oberheim Four Voice (FVS-1) Restoration – Part 8: The SEMs


In the spirit of saving the easy stuff for last (…or so I thought), I tackled the restorations of the four Synthesizer Expander Module (SEM) units.  These were more work than I had anticipated, but then again I opted to completely disassemble them, clean, re-cap, and repair any issues along the way. Fig. 1 – […]

Oberheim Four Voice (FVS-1) Restoration – Part 7: The Programmer


In 1976, the Four Voice began being offered with a programmer module.  Oberheim’s  patch storage implementation was a bit different from that of the microprocessor-controlled polyphonic synths to follow (Prophet-5, OBX, etc…) in that it was capable of  multi-timbral storage/recall of sounds.  In other words, each SEM could be setup differently using the programmer’s controls […]

Oberheim Four Voice (FVS-1) Restoration – Part 6: Cosmetology


I’ve been making some progress on this restoration, and thought I’d lump together a bunch of the more superficial, cosmetic-oriented work in this post. While I’ve had the synth chassis separated from its roadcase, I felt that it would be a good time to freshen things up a bit.  The I/O and power supply panels […]

Oberheim Four Voice (FVS-1) Restoration – Part 5: Keyboard Rehab


Forging on ahead, I felt it was time to give this keyboard some new life.  The bushings were pretty much shot, and several were starting to crumble away – yielding the all too familiar snaggletooth keys and loud metal-on-metal action:     Getting the Four Voice’s keyboard assembly out involves excavating the synth from its […]

Yamaha CS-40m


These are some photos of my old CS-40m.  I loved the filters and ring modulation in this synth, and it was built like a tank!  The design lacks some niceties like FM and sync between VCOs, but it was still a joy to play.   This synth also interfaced well with my modular.  Here it is with […]



This track features a Korg X-911 Guitar Synthesizer processing an Alembic Distillate bass for the majority of the synth and synth-bass parts.  The regular bass sound is also the Alembic, and there’s a fair amount of RE-301 Space Echo in this as well. Squelch



I recorded this right after acquiring a 1973 Gibson Triumph (Les Paul Recording bass) from the original owner who had it in storage since around ’75!  The original flatwounds were even still on it. =)  They were sooo dead, but had this nice “plonk” sound to them – and so began this track… The melody […]

Oberheim Four Voice (FVS-1) Restoration – Part 4: Hearing Voices


Now onto the fun stuff…  I’ve been seriously digging this thing even as it limps along with two-voice polyphony, but its time to hear a happy quartet of SEMs! SEMs 3 and 4 were not firing from the keyboard, and the continuous assignment mode would only step between SEMs 1 and 2.  Between all of […]

Oberheim Four Voice (FVS-1) Restoration – Part 3: The PSU


  Before venturing too far down the path of sorting through the faults, I wanted to first ensure that the power supply was in good working order – that the power output was clean, and that the rails were putting out the correct voltage. There are a total of six capacitors on the PSU board […]

Oberheim Four Voice (FVS-1) Restoration – Part 2: Modification Removal


Well, where to begin… I thought I’d start by tracing out and removing the modifications.  Overall, the mods looked to be in a questionable state, and I felt it would help in troubleshooting the primary issues if I could rule-out the modifications as a contributing factor. The “Mediamix Triangle Mod” board was held in place […]

Oberheim Four Voice (FVS-1) Restoration – Part 1: Introduction


I’ve been fascinated by this synth most of my life, and I finally got a chance to lay hands on this one in June 2011. In or around 1975, Oberheim released the four voice polyphonic synthesizer (dubbed the FVS-1), which was basically comprised of four Synthesizer Expander Modules (SEMs; keyboardless, monophonic synths that were originally […]

Refinishing a Thunderbird Bass


I’ve been dabbling with guitar/bass repair for years out of necessity and I’ve always wanted to try my hand at refinishing a bass, but I’ve never had the right candidate to practice on… until now. A Czech-made clone of a 1965.5 to 69 Gibson Thunderbird bass (referred to as the “non-reverse” body style) came into […]

Fun with Breadboards!


I snagged an old Heathkit “Electronic Design Experimenter” off Ebay for around US $23, when all was said and done. Didn’t think I’d be excited about a breadboard – but this thing’s neat!  In addition to the breadboard, it contains a bi-polar power supply (each rail independently variable up to 15V), pads to distribute 15 […]

Modular Synth Walnut Cabinet Refinish


I had obtained a 44-space walnut studio cabinet slated for the top-most portion of the modular.  This cab had originally been purchased from Synthesizers.com, and it appeared to be very well loved with its share of road rash (and some extra holes from those Dotcom mounting brackets). My current cabs are still in great shape, […]

Roland Space Echo Motor Rebuild


Thought I’d share some info and pics about a recent Space Echo motor rebuild, in case it helps anyone else… About a year-and-a-half ago, my RE-301 started acting up. The fastest motor speed seemed really slow and erratic, and at the slowest setting it would warble down to a halt. I noticed a lot of […]

Sequential Circuits Pro-One Pressure Sensitivity Retrofit


My Pro-One had died a ways back (an op-amp in the keyboard’s CV path had bit the dust), and while I was in there repairing it and doing some other maintenance (PSU filter caps, keyboard bushings) I was thinking that it’d be slick to try and add pressure sensitivity to it.  Having just finished refreshing […]

1972 Guild JS-II Bass Alembicized Bridge and Pickups


This post details a couple enhancements made to my ’72 Guild JS-II bass back around 2007. I wanted to try out some Hammon Dark Star pickups (recreations of the Alembic-modified Hagstrom Bi-sonics favored by the likes of Jack Casady and Phil Lesh), and also address some issues with the stock bridge relating to intonation and […]

1969 Gibson EB-0 Pickup Coil-tap and Series-parallel Modification


Here’s a relatively low cost modification that I implemented a few years ago on my ’69 Gibson EB-0, and the results were rather useful.  This bass’ wiring was not original to begin with, and so I figured it’d make a decent candidate for some tinkering. I was curious about experimenting with different permutations of the […]