Fulltone TERC TSC-618 User Manual

Model tsc-618

Congratulations on your purchase of the

If you are a session guitarist, you’re “not-quite A-List” until you have a Tri-Stereo-Chorus in your rack! It is the single most

identifiable and certainly the lushest stereo chorus ever made, heard on tons of recordings from Joni Mitchell to Don

Henley, Madonna to Eric Clapton...Lukather to Landau. Made for a brief time during the 80's and released under the

Dyno My Piano, Songbird, and Dytronics names, it went through many circuit changes. Just what is a Tri-Stereo-Chorus?

My Electronic Engineer John Greene and I are two of only a handful of people who can answer that. I own 6 of them and

have documented and repaired dozens more. TSC’s are actually three separate chorus circuits, each using a Panasonic

MN3007 Bucket Brigade (BBD) chip to create its delayed signal. These three choruses are treated with multiple modula-

tions and mixed together across the stereo output field in a way that, not only, creates complex images, but creates

Phasing artifacts as well. Add to this a 30 volt internal power supply, and you have a super high-headroom rack unit that

sounds warm, huge, and doesn’t distort when interfaced with high-level rack systems and studio patchbays.

Production of TSC’s ceased in the late 80’s, and since then the price of these on the used market has skyrocketed to

$4000 and more. The funny thing is, almost all of the ones that I’ve checked out were so poorly maintained that often

times one channel or more wasn’t even working! It’s all about the trimmer adjustment on the delay chips..if those are

adjusted improperly they can sound weak and noisy. And now along comes the Fulltone Custom Shop “That 80’s Rack

Chorus” (TERC for short) to save the day. Better constructed than the orginal but 100% the same circuit using better

quality parts such as metal film resistors in the power-related areas for less noise, and gold plated sockets on key

opamps that (should they ever fail) will be as simple as us mailing you a new part and you just popping it in.

I have sourced enough N.O.S. Panasonic MN3007 Delay chips to build a production run of around 3200 units of "That

80's Rack Chorus” and to service any in the future, if necessary. I have also produced many custom parts for this

project, including pots, switches, transformers, and photocells, but just the thought of only 3200 of these ever being made

with the T.E.R.C. logo one them... drawing heavily from my love of the vintage Looney Tunes cartoons "That's all Folks"

font... just puts a smile on my face. Enjoy!

Michael Fuller / President

Model TSC-618