To: analogue@hyperreal.com,
From: gstopp@fibermux.com,
cc:
Subject: Emerson Moog secrets (really long)
Date: Thu, 07 Dec 95 12:03:49 PDT
Sorry y'all in advance for the size of this post.
Excerpts from a 12-6-95 Email from jdm@synthcom.com:
>
>Is this BEFORE or AFTER the mods you guys did? :)
>
Before! We did nothing to the sound, we just made the sound more
predictable and stable.
>
>But is $5000 for a System 15 worth that much more than a $1000
>MiniMoog?
>
Well, I wouldn't pay $5000 for a System 15. I'd pay $1000, maybe $2000
max (yes, even these days) but that's based on my own situation so keep
that in mind. So they're almost even price-wise, and the modular will
make better noises. But I wouldn't be without a Minimoog too, myself :)
>
>Oh come on Gene, we're not going to let you off THAT easy. Give us
>the gory details (we could use more words on modular synthesis here)!
>
Ow! Twist my arm! Oh okay. Here goes: first, see the chapter in Mark
Vail's "Vintage Synthesizers" book about this machine if you want
physical details about what's where. Okay, the main console near the
bottom has all the main sound-producing modules in it. First there are
three VCO's, each made from a 921A Oscillator Driver/921B Oscillator
Slave pair. Now traditionally there are two or three 921B's for each
921A, but in here it's different. Under the VCO's are two CV
routing/Mixer console panels (model = Console Panel #3). VCO 1 and 2 are
controlled by the CV routing on the leftmost one, and VCO 3 is by itself
on the CV routing of the rightmost one. Each CV routing panel has four
switches on it, for switch control of system-wide CV's to control the
attached VCO's. On this system, CV1 is the keyboard, CV2 is the ribbon
controller, CV3 the the output of the sample & hold, and CV4 is external
(seperate per panel on a 1/4" jack). The VCF a few modules over also has
a CV routing panel, except on this one CV4-external is a
voltaged-controlled reversible attenuator that is controlled by the
programmer upstairs as well as the panel knob. All of these CV routing
panels as well as the S-trigger routing panels are an important part of
live sound changes - I'll get back to these later.
The Mixers in the two console panels under the VCO's are
voltage-controlled by the programmer upstairs with Vac-Tecs. The
sawtooth outputs of the VCO's go to one mixer, and the square outputs
plus noise go to the other. Both mixer outputs go to the VCF (which is
modded for multiple inputs). The output of the VCF goes to a VCA and
envelope generator to provide the main lead sound output. The sine
wave output of VCO 3 bypasses the VCF and goes to its own VCA and
envelope generator. Another envelope generator goes to the VCF
reversible attenuator mentioned above, and yet another envelope
generator goes to the CV4 input on the console panel that controls
VCO's 1 and 2. All envelope times are controlled by the programmer
upstairs, with Vac-Tecs on the time contant pots, so you have to turn
them all up or else the front panel will override the programmability.
The envelope generator that sweeps VCO's 1 and 2 is used for the
"Hoedown" sound - some attack, all sustain, no release. The program for
this sound must be selected - VCO 1 tuned to the root, VCO 2 tuned to
the fifth, VCO 3 tuned to the root and not swept by the envelope because
it's on a different console panel CV routing thing. This envelope, with
a different patch, is also used in "Aquatarkus" live for the falling
tone thing, with attack = zero, sustain = 0, and decay = long.
Keith had a certain technique to get his long climbing pitch sweeps.
The trick is to start at the low end of the keyboard, turn portamento
up all the way, and then "walk" up the keys slowly. You can't just hit
a low key then a high one, because since this is exponential portamento
the pitch will just zoom up. This way he controlled the slow climb
rate. Also he played legato but lifted keys enough to cause S-trigger
glitches which would fire off the envelopes randomly during the climb.
We can use "Aquatarkus" live (I think it's on side 3 of the vinyl version
of "Welcome Back My Friends...") to demonstrate all this stuff. First,
assume VCO's 1, 2, & 3 into the VCF into the VCA, no modulation, all EG
times = 0, all sustains = max, VCO 3 sinewave VCA/EG off (via console
panel S-trig switch). Then:
*Beginning of song, organ intro, synth lead with VCO's tuned
root-fourth-fifth.
* Change preset to VCO unison w/filter sweep
* Guitar chord/feedback during synth silence for re-configuration -
disconnect VCO's 1 and 2 from all CV's so they sit at a low droning
fifth interval, sample & hold at low sample rate through heavy lag
randomly changing the VCF cutoff for a background "WWOOOOWWW" effect,
VCO 3 sine wave solo turned on to play over this. The sample & hold
also slowly triggers the main sound envelope, which has a long
release, so that the drone is sustained. This goes on for a while,
sine wave theme is from Dick Hyman's "Minotour", I believe.
* Solo ends, short silence while VCO's 1 and 2 are re-connected to
CV1, the sample & hold infulence on the VCF and S-triggers is shut
off, and delayed vibrato is added from some modules in the expansion
cabinet above the main one (921 VCO at low frequency, gate-delayed
envelope generator and mod depth VCA) and the patch is changed to
VCO's in unison with the filter wide open and envelope times zero.
* Modular and Minimoog played together, in the typical Emerson
"stretch both arms out and play two keyboards across from each other
at the same time" style. The Minimoog is on top of the Hammond L-100,
across from the C3/Modular setup.
* Solo gets a little delayed while "Hoedown" envelope generator is
kicked in on VCO 1 and 2 CV4, set for attack = 0 and long falling
decay, and portamento is set to max for the "walk up the keyboard".
The EG fires off once in a while during the climb.
* VCO 1 and 2 EG mod turned off, solo ends. You may notice that the
vibrato gets left on all the way to the end of the song.
Okay now it may appear that I have devoted my entire waking life to
the pursuit of figuring out old ELP solos, but that's not the case!
Believe me! I just happen to remember all of this from about five
years ago. Okay I'll go on.
Regarding the ribbon controller - flip on CV2 on all console panels
and the ribbon controller takes over. Oh yeah don't forget to enable
it on the S-trig panel as well or the thing won't make any noise.
Anyway during the ribbon controller solo in "Tarkus" (side 2, after
"Stones of Years", I forget the name of the part) there's some "ray
gun" noises produced by the ribbon controller - the pitch starts high
and falls rapidly like repeated envelope triggers with attack = 0,
decay = tiny, and sustain = 0. Here's the real story:
On the Moog 956 Ribbon Controller there is plastic coating on the metal
ribbon to insulate it to keep the holding capacitor charge from being
discharged by your finger so the pitch doesn't droop. Well on Keith's
ribbon there is a gouge take out of the insulation about 7/8 of the way
up, so if you touch this part the pitch will fall as the cap gets
discharged through your finger. If you're comfortably sitting in a nice
cozy living room playing the Moog it will discharge slowly. If you're
on stage under hot lights sweating like a pig it will discharge quite
rapidly. Press the ribbon down to the current strip and then let it up
but keep your finger on the ribbon, and this is the effect. Now I don't
know it this insulation was scraped away intentionally or if the ribbon
got run over by a road case one day....
There's a few other things, like the sequencers controlling another
voice made out of modules above the main console, or more esoteric FM
effects, that are more subject to speculation so I can't be specific
about those patches. I could ask Keith about it but 1) he probably
won't remember and 2) he probably doesn't WANT to remember. One does
get sick of things after a while, after all, even big Moogs.
Alright enough typing for now. Hope this was interesting....
- Gene
gstopp@fibermux.com
______________________________ Reply Separator _________________________________
Subject: Re: Re[2]: ELP's Wasted Moog (was: Re: Re[4]: Serge Users)
Author: "J.D. McEachin" <jdm@synthcom.com> at ccrelayout
Date: 12/6/95 12:45 PM