From: Grant Richter,
Subject: Re: [AH] Re: Blacet vs. Wiard VCOs - compare/contrast...anyoneown
Date: Mon, 08 Mar 2004 15:13:49 -0600

> The Blacet VCO was designed with some tips from Grant and a contributor
> to Electronotes (Terry?). The basic core is pretty much the classic
> sawtooth engine with some further temp comp based on the original EMU
> modular. Some original stuff includes the VC octave switching and
> calibration circuit and the VC waveform.

Terry Michael (formerly Terry Mikulic) when he was a teenager, contributed a
significant number of the core circuits published in Electronotes magazine
(something like 50%, including the first state variable VCF using OTAs EN#33
Pg. 5, and EN#34 Pg. 16,17).

In particular, Terry perfected and published the "classic sawtooth engine".
While sawtooth reset designs had been published by Michael Suchoff (EN#49
Pg. 11) and Paul Titchener (EN#57 Pg. 8), Terry's design (EN#62 Pg. 14 Feb.
1976) is the most widely copied.

This design was picked up from Electronotes magazine by the engineers at
Moog Music Inc. and others. The design forms the basis for the VCOs used in
the Micromoog, Source, Prodigy and the other small Moog synths.

No money or acknowledgment was ever paid Terry for the design. It was not
legally required, since by publishing the design (at 22) he placed it in the
public domain.

Terry continued to improve the design over the next 25 years, and I
connected John Blacet with Terry Michael's updated and improved sawtooth
engine. This design is technically superior to the VCOs used in the Moogs
and all other copies of Terry's older design.

Unfortunately, John apparently did not realize that Terry is the originator
of the "classic sawtooth engine" and the other VCOs he studied were copies
of Terry's "first" design.

LUCKILY, in spite of the confusion, John Blacet kept the important parts of
Terry's new design and they appear in the Blacet VCO!

To summarize:

The Blacet VCO is the only commercial version of Terry Michaels "improved
sawtooth engine" (remember the old inferior version sold something like
50,000 copies).

The Blacet VCO is the ONLY version of the "sawtooth engine" officially
licensed from the originator of the design.

Best Regards,

Grant Richter
Wiard Synthesizer