[sdiy] dx, chorus and Spock

[Gene Stopp]

Ooops sorry! Maybe you should listen to IQ also! Vast analog synthesizer
noises. Very Genesis-like with the occasional gothic-metal. Start at their
latest and work backwards. And once again of course a bunch of great guys,
even if they don't make it across the pond very often.
http://www.gep.co.uk/iq/

This message intended for any die-hard progressive or neo-progressive heads
(generally older farts like me who remember flowers, black light posters,
kool-aid, and lava lamps).

Uh oh better get back towards on-topic.... let's see, what DIYish thoughts
have been travelling around in my head... oh yeah, here's one:

Do precise waveforms sound better than "sloppy" ones? What do I mean by that
anyway? A few years back I worked for a company that was closing up their
California division. We had a six months notice and I stuck it out to the
end in order to collect severance pay. With lots of spare time and some
expensive test equipment, I sat around and made synthesizer circuits. Yes
those were the ASM-1 days. :)

I remember building a 4-pole OTA VCF (Electronotes 4-pole 3080 design) and
it sounded gorgeous.  As I ran a sawtooth into it and swept the cutoff with
resonance turned up a little, it was passing through each harmonic in the
signal as though I had a big mixing board in front of me with all of the
sinewave harmonics in order, and I was fading them in and out one by one in
sequence. Literally it was like 8th, 7th, 6th, 5th, 4th, 3rd, 2nd,
fundamental all by themselves, clean, loud, and crystal clear. I was wearing
headphones at the time and I sat there doing this for hours (or so it
seemed). I was mesmerized.

I can't do that on any synthesizer, it seems. I've tried to get the same
effect since, but no luck. Was it my signal source? I'll bet it was - I was
using a big HP3325 frequency synthesizer/function generator. The analog
waveforms were good up to 11 Mhz, I seem to remember. So in the audio range,
the waveforms were about as close to a math-class graph-paper function as
you could get. The sawtooth slope was a perfectly straight line, and the
reset trace was a perfect infinite slope (i.e. invisible on the scope). No
jitter, no smearing, no rounding, no noise, nuthin. I think this made all of
the spikes on the spectral plot exactly where they theoretically should have
been, at exactly the right amplitude. I don't think that synthesizer
oscillators have this kind of perfection and therefore their spectra are
less than ideal ("smeared"?), so you never get that one-sinewave-at-a-time
sound.

Thoughts? Experiences? Anybody with an HP3325 or similar source of perfect
waveforms wanna do some filtering tests? I do see them on ebay all the time
with a wide range of prices. Maybe I should lurk for an "as-is" 3325. But
they're so bloody big.

- Gene


-----Original Message-----
From: jhaible [mailto:jhaible at debitel.net]
Sent: Thursday, August 15, 2002 3:27 PM
To: Gene Stopp; synth-diy at dropmix.xs4all.nl
Subject: Re: [sdiy] dx, chorus and Spock



> Yes I know these guys!!! - I think my name is in the liner notes on one or
> more of their CD's. :)

Great!

Why did it take me so long to find this music ?! You should have told me!
(;->)

JH.