Picture of an A/DA Flanger prototype, circa 1976.

What are good models of flangers?

"My favorite is probably the A/DA flanger, reissued in the late 90s. And A/DA has re-reissued it a new version again in 2010!!! This was our best selling pedal ever when we got them in January, 2010."
- AnalogMan.com


The Story of Seamoon and A/DA

By Chris Gill

Welcome to “The Stompin’ Ground.” This column will be concerned with what may be the final frontier in the vintage market-classic stomp boxes and vintage effects. We’re going to trace the history of the companies that made some of today’s most collectible pedals, as well as look at the follies of the brave individuals who failed. We’re also going to examine the incestuous family tree of the development of various pedals, and reveal long-hidden information about the origin of the earliest effects.

The Phases of Seamoon

In the early ’70s, Berkeley, California was a thriving hippie community (and in some respects, it still is today) that attracted flocks of creative individuals to its hills. The main campus of the University of California is situated there, and many aspiring electrical engineers came to Berkeley to study. Of course, the San Francisco Bay Area also enjoyed a thriving music scene, and many of these engineers found employment for bands like the Grateful Dead and Santana (Furman, Alembic and Mesa-Boogie are just a few of the companies that got off the ground by making products for Bay Area musicians).

Seamoon Ltd. was established in Berkeley in 1973, when Craig Anderton, who later gained fame for his articles and columns in Guitar Player magazine, and for his book Electronic Projects for Musicians, solicited a music store in hopes of selling a pedal he developed. “I had come up with the circuit for an envelope follower that later became known as the Funk Machine,” says Anderton. “I had a friend named Larry Schreiber, who was familiar with a music store in Berkeley called Skatzenbag Music. I took it in there to see if John Lang, who owned the store, was interested in selling it. He ended up taking it to a NAMM show and got orders, so we decided to make the thing.”

Shortly thereafter, Lang founded Seamoon, and started making their first product, the Funk Machine. The original units featured range and sensitivity controls, and were housed in a Bakelite box. However, too many overeager funksters crushed the box with their feet, so later versions were housed in simple aluminum boxes held together with six screws. The circuit was deceivingly simple.          “It contained two op-amps with an opto-isolator to do the actual envelope detection,” says Anderton. “It’s that famous opto-isolator sound that everyone is rediscovering. Because the opto-isolators are all a little different. Every Funk Machine varied slightly. It wasn’t anything obvious that would make someone go, ‘Oh, I’ve got to have this one instead of that one.’ But there was a tiny variation. It was an analog world, and in some respects that added to the character of the thing. Part of the testing process was very subjective. If it didn’t work properly, we would pull the opto-isolator and solder in another one.”

Martha Davis, who later became famous as the lead singer of the Motels, was an early Seamoon employee who did a lot of the company’s assembly and testing. According to Anderton, she developed a peculiar method of testing the Funk Machine. “She tested them by running her fingers over particular parts on the circuit board. By noticing how the hum was affected, she was able to really nail what was going on with the unit. It was very cool. Her finger hum testing technique was flawless.”

Soon after hitting the market, the Funk Machine fell into the hands of several famous musicians, including Steve Cropper, who bought one of the very first units, and funk bassist Larry Graham. “He was really big on it,” says Anderton. “When he was on TV once, he held it up in front of the camera. It was a big part of his sound.”  Shortly after designing the Funk Machine, Anderton came up with the circuit for Seamoon’s Fresh Fuzz distortion pedal. This circuit was a simple op-amp based device with gain and bite controls.  “It was really basic,” says Anderton. “It used regular diodes. If I was to design it today, it would be a lot different.” The unit was a favorite of Tom Scholz, of Boston.  These products remained the mainstays of Seamoon’s product line through most of the mid ’70s, although the company also introduced an ill-fated battery-powered solid-state amp called the Peter Portable.

By 1976, Seamoon had undergone significant changes. Anderton departed the company, the cosmetic appearance of the products was redesigned and several new products joined the lineup. However, it was also the beginning of the end of Seamoon and the dawn of a new company that would carry out Seamoon’s ideals and ideas with even greater success.

Sometime in 1975, a young Berkeley musician named Dave Tarnowski started working for Seamoon. He got the job after walking into Skatzenbag Music and impressing owner John Lang with his technical knowledge. “One thing let to another and I started working on some musical effects,” says Tarnowski. “The first musical effect I designed for them used early bucket brigade devices from Reticon. These are earlier than the bucket brigades from National or Panasonic. I actually did some R&D work at Reticon Corporation. I picked up a few of the chips to see if I could make a time modulator.”

Tarnowski designed the Studio Phase, an impressive phase shifter with intensity, shift and speed controls that originally retailed for $129. Other products in Seamoon’s line at this time included a cosmetically updated version of the Funk Machine, and a distortion box called the Controlled Tone Preamp, which featured volume, tone filter and distortion controls. A product called the Two-Track Delay was announced in the summer of 1976, but it was never released to the public.

The Birth of A/DA

By late 1976, Seamoon was having financial troubles. It was difficult to compete with companies like Electro-Harmonix and MXR, who were biting into their market share and gaining headway on the west coast, where Seamoon’s sales were strongest. Tarnowski was confident the effects pedals he wanted to build would be commercially successful, so he bought up the remaining Seamoon inventory in late 1977 and formed A/DA (Analog Digital Associates) in early 1978.

A/DA’s first product was the A/DA Flanger, which Tarnowski started designing while he was working for Seamoon. “It had a few features in it that no one else was doing and no one else has duplicated since.” says Tarnowski. “The main feature was the wide range of minimum to maximum time delay, which was a 40:1 ratio. Most flangers are 20:1 or less. Secondly, when it sweeps up, it sounds like it sweeps to zero time delay. It actually goes up to infinity, which is what true tape flanging sounds like. Another unique feature is the even/odd harmonic switch. The regeneration is an enriched overtone and harmonic recirculation path that no one else has ever done, as far as I know. It has a warmer, richer tone to it when it goes into higher regeneration, rather than just pure white noise and brittleness. There’s also a gate that allows you to set the flanger so it only comes in at higher dynamics, and there’s a noise gate that squelches any residual noise when the signal gets low.”

Tarnowski started selling his flangers in January of 1978, driving to dealers with the finished product in his trunk. His first was Don Weir’s Music City in San Francisco. “I had spoken with Reese Marin, who was the manager, and I had showed him the flanger after much cajoling,” says Tarnowski. “He was very impressed, as was everyone else in the store. He looked at me and asked, ‘Do you have any more of these with you?’ I had 11 or 12 in my trunk, so I went out to get them. When I came back, Reese had already sold the unit that I was demoing. It was sold to Steven Gerr, who is now an L.A. studio musician. He got serial number 3. He has it in the original box with the original invoice and everything. Serial number 1 was a rat’s nest prototype that never worked right. Serial number 2 is my unit.”

The Flanger became A/DA’s most successful pedal, shipping more than 50,000 units before it was discontinued. A/DA reissued the pedal two years ago, and it has once again become a top seller. A/DA issued two other pedals, the Final Phase and the Harmony Synthesizer, but they didn’t sell quite as well as the Flanger. About 5,000 units of the Final Phase were shipped, and only 950 units of the Harmony Synthesizer reached the market.

The Final Phase was introduced in 1979. Featuring a built-in distortion unit, the Final Phase is one of the most versatile phase shifters ever produced. “It uses a ’70s-style op-amp distortion circuit,” says Tarnowski. “The Fresh Fuzz was built around a similar design. But the Final Phase was done in a way that a single knob could control the amplitude and the amount of distortion. That, combined with the phase shifter, really elevates the fuzz in a way that sounds like a jet blasting off.”

The Final Phase is a six-stage phase shifter that provides 540 degrees of phase shift. There were several clever innovations in the unit’s design.

“It has sweep modulation, which allows you to superimpose another sweep pattern on top of the primary sweep.” notes Tarnowski. “It’s like a Bi-Phase. You can modulate the sweep so you can get vibrato. The most sonic feature is the phase shift design. Most phase shifters are usually a phase splitter transistor, like the original Uni-Vibe or an op-amp all-pass phase shift network. Both of these circuits have a Q of 1, which is a very steep notch. It’s so steep that as it sweeps you can get it to de-tune the pitch severely, almost like a flanger, but it’s arithmetic instead of logarithmic. It’s a little non-musical, but very interesting sounding.”

A/DA’s rarest effect, the Harmony Synthesizer, was also its most complex pedal. Tarnowski started work on the unit while he was employed by Seamoon, but it took several years for him to accomplish his goal.

“That was the world’s first and only analog bucket brigade pitch transposer,” he said.

The Harmony Synthesizer provided 200 milli-seconds of delay and could create harmonies to chords or single notes. The harmonies could be preset to two different intervals users could access with a footswitch. Bypass and delay functions were also footswitch controllable. Housed in a cast aluminum case, the Harmony Synthesizer looked similar to the Flanger but was about four times larger and had twice as many knobs.

“It was a big breakthrough to use bucket brigade devices for that application,” says Tarnowski. “It also had a foot controller input that allowed you to bend notes. It was a precursor to the whammy boxes out there now.”

Two Harmony Synthesizer units ended up in the hands of Robert Fripp, who still uses it frequently.

In the early ’80s, A/DA discontinued its pedals and started producing rack-mountable analog and digital delays. However, Tarnowski, who still works at A/DA, has reissued the A/DA Flanger and Final Phase and is reissuing the Seamoon Funk Machine and Fresh Fuzz under a new division, called Rocket. The division is also producing a line of combo amps based on vintage circuits, and reissuing Carrotron effects.

“We have the rights to a few of the older manufacturers’ designs,” says Tarnowski. “The company has invested a lot of R&D. We’re going to be introducing a lot of products in the next two years.”

Chris Gill is Editor in Chief of Maximum Guitar magazine. He is also the author of Guitar Legends – The Definitive Guide to The World’s Greatest Guitar Players (Harper Collins). Questions and comments can be sent to him in care of Vintage Guitar or via e-mail at:  cgill at themomi.org