Selecting OTAs in the '70s (was: BA662's...)

Joachim Verghese jocke at
Sun Jan 12 20:46:23 CET 1997

On Sun, 12 Jan 1997, Synthfool wrote:

> Roland did use the 662 in many products, but it should be noted that they
> were graded and marked with a colored dot. Usually for offset, I believe.
> (I have the rating criteria around here somewhere, but as I remember it,
> they followed resistor colors codes and white was the best they graded to.
> Replacing a 662 marked with a red dot with an orange dotted unit was
> sometimes ok, but not the other way around... see?)
> Polyfusion did the same with 3080's. Gold dots were better than silver dots
> for them.

I think most manufacturers had to select 3080s. ARP's 3080s had blue
and red dots for offset and noise (or vv). EMS also selected theirs for
noise. What about Moog?


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