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Subject: RE: Milestone approaching / News

From: "Dave Bradley" <daveb@...>
Date: 1999-07-20

> Other stuff:
> 1) How many chips does one get from On Chip for $38,000? I'd
> still like to
> see this happen eventually.

Clue me in - what are we talking about here???

> 2) I've been looking at the Emu stuff at Silicon Breakdown, and I was
> wondering how similar the Resonant Filters were to the MS10 (and
> MOTM 410)
> VCF -- Dave? Paul?

The EMu Resonant Filters are classic 2 pole (12 db/oct) state variable
filters with simultaneous LP, BP, and HP response available. They were
relatively low cost modules that were designed to be stacked one or more
together. The different outputs were combined in a mixer so you could mix LP
with HP, etc. The basic module didn't have any voltage control brought out
to the front panel - you used one or more for static formants or bought a
separate filter controller module that could be hooked up to 2 banks of 3
filters with a ribbon cable behind the front panel.

EMu also made a VERY full featured stand alone state variable filter (the
Universal Active Filter) with VC freq & Q, keyboard percussion input ala the
Arp 2500, separate filter outputs, etc.

I can't compare these to the MS10 since I don't remember it, but the 410 is
3 separate bandpass filters each with its own tuning (along with built in
LFOs to drive sweeps). If you took 3 Emu Resonant Filters, used their
bandpass response, hooked up the controller module and a LFO, you could sort
of approximate the 410, but it wouldn't have those cool Vactrols for squishy
response.

Comparing them to the 420, the 420 has notch response, they have bandpass.
The 420 has fully temp compensated VC, the Resonant VCFs have simultaneous
outputs (NOT on separate jacks, however!)

Of all the MOTM filters Paul has talked about doing (SEM, Moog, Xpander),
the SEM is 2 pole LP, Notch, HP like the 420 (but continuously sweepable),
the Moog is 4 pole LP, the Xpander is 15 different combos of poles and
responses.

Dave Bradley
Principal Software Engineer
Engineering Animation, Inc.
daveb@...