[gml]

gentle men and women of Gearslutz,

here's the history of the 8200.

in the early 80's Ron Pendragon and i built a 5-band stereo EQ based largely on the EQ design of the GML/Nova boards at the Complex and on the road with Nova Sound (touring sound reinforcement co). this basic parametric eq design has changed a bit since the first ITI in 1971, and some of the changes have been substantive.

for instance, in the Sontec EQ design of 1976 or so i dropped the inductor that was used in the low-frequency shelf, redesigned the discrete op-amp (the first of the blindingly fast FET-input designs) AND implemented a terse, three-transistor inverter in the single-stage peak filter.

but since 1982, after we re-focused our product to better embrace reliability (the Sontec stuff is not reliable in any sense of the word), we settled on a design that is more or less unchanged since then. the differences (aside from having to change componentry as parts went obsolete - which happens more often than you'd like) are: 1> replacing the toggle switch and led indicator with an integrated led-illuminated pushbutton & 2> replacing the 5534 inverter in the peak filter with another GML 8802 discrete op-amp. the latter change made the performance of the unit more consistent; lowered the noise floor; and improved headroom, HF distortion and stability margin. it was and is the expensive way to go, but given a level-playing-field (more about this later), i think one would likely choose it on the basis of the more transparent sound.

we still service everything we've ever built (save GML Automation, with enough sub-assemblies which themselves have gone obsolete, which we no longer support).

George