.... iT'S interesting that old Moog Modulars use both S-trigs & V trigs.
Triggers might be produced by sequencers, the key on a keyboard, drum controllers & foot pedals.
They are useful for starting an envelope generator or advancing a sequencer.
A S-trig is just a passive switch closure to ground.The voltage starts high, and when the trigger occurs the voltage shorts to ground. It's also known as a switch trigger or shorting trigger.
Moog Keyboards produce S-trigs.
Moog 911 Envelope Generators need S-triggers to start their cycle.
In comparison, V-triggers start at zero volts and rise to a standard level .. usually 3V.
The 911 plugs into the Moog modular using a 22 pin PCB/edge card connector.
It's a ADSR envelope generator.
The pin out is as follows:
3. -6V14. Trigger out
21. to Trigger switch (Jones S-302)
The Moog manual suggests a regulated AC supply, such as a Moog Model 901 or dry batteries.
Max current is 50 milliamperes.
Range of T1: 10 ms to 10 secs (attack)
Range of T2: 10 ms to 10 secs (delay)
Range of T3: 10 ms to 10 secs (Release)
Range of Esus: 0 to Emax
Esus = sustain.
Emax = voltage at which T2 begins. = 5.5V +/- 10%
You trigger the 911 by closing a switch. So unlike most EG's you will encounter today, no voltage is supplied to trigger the module ... its quite the opposite.
The 960 sequencer produces V-triggers.
V-triggers start at zero volts and rise to a standard level .. usually 3V.
The V-trig uses the standard 1/4 inch jack.
So how do you get a trigger from the 960 sequencer to start a envelope cycle of a 911 EG.
To convert triggers from one to another, you can use a special conversion cable or the 961 interface
There are 2 types of this module..... the P (portable) and the C (console).
The above module is the P-type ... used for portable systems.
Plug in any audio source (like an old drum machine) into the jack on the left.
It will be transformed into a voltage trigger.
The control is a sensitivity knob.
The console version has this section right at the top of the module.
My module, has been modified somewhat, so may look a bit confusing. However, the V-trigs (from your 960 sequencer) enter into the jacks on the left, and S-trigs exit via the dual blade Cinch J plug.
There are 2 input sections: A & B
Any inputs into column A will have the same duration as the outputs
The Column B in jacks are connected to a Switch-On Time knob.
This allows you to control how short or long the “ON” duration is for S-Trig signals. (40ms to 4 seconds). You can use this to trigger the 911 envelope generator.
+ Here are the Mouser links for the Moog connector hardware:
Moog models using the S-Trigger system
- Moog Modular System 15
- Moog Modular System 35
- Moog Modular System 55
- Moog Modular System 3C
- Minimoog Model D
- Moog Sonic 6
- Moog Liberation
- Moog Source
- Moog Taurus
- Moog Prodigy
- Moog Rogue
- Moog Sattelite
- Moog Ribbon Controller
- Moog Sample & Hold Controller
- Moog Drum
- Moog 1130 Drum Controller
- Moog Modular Keyboards
- Moog Mother 32 ??