Has anyone any information on what a Tangent generator is?
Ive recently come across this but there’s not much info out there concerning synth wave shape/controller etc.
The Moog lowpass ladder filter is an arctangent generator, so the highpass filter may be the tangent generator.
Thanks…I have no idea what Tangent generator is , yes I agree, sounds like High Pass but I had the feeling it was something to do with CV…maybe like white noise random thing but more controllable
…I haven’t seen or heard any description but it is mentioned on the
Moog 900 demo record with small sample.
Only have the recording on the 1967 R.A.Moog 900 series demo. Around the 4:11 mark the announcer describes the transient generator? (aka the 911 envelope generator?). His pronunciation does sound like he puts a “G” in the middle of transient. And the CV controlling the oscillator sounds like two 911’s to get the quick upward swing, followed by a slower upward swing.
Not sure if I have a copy of the later Chris Swanson demo record.
Mystery modules I have not yet identified/verified are the 906 Impulse Generator and the 913 Triggered Envelope Generator. The 913 may simply be a dual Schmitt trigger section of the 912 Envelope Follower. Have seen such a module on an early system where there is one “signal” input and two sections each with a threshold dial and two each 1/4" S-trigger outputs. Those early systems had not yet implemented the dual prong Cinch-Jones male type for all S-trigger outs. This would be usefull for syncing any external signals to trigger the Moog. I use the Schmitt trigger section of the 912 for such triggering all the time.
The 906 is a complete mystery?
(Description from 1965 catalog: 906 IMPULSE GENERATOR: Generates a wide variety of transient waveforms for use as signal or control voltage.)
The other mystery module was the 902A Bandpass Filter Adaptor. This was recently unveiled in an Australian E-bay auction. There was enough info in the auction photos to reverse engineer the module. Will post info when I construct one. 
Thanks CZ …I will re listen …your probably right, hard to tell his word. its not exactly HiFi. But yes it does sound like 911s combined in a clever way.
Thanks for taking the time to listen .
I’m still looking at the odd modules but those early ones are pretty fascinating particularly when you dont know their full in function
Listening again the announcer says Tran-she-ent. Looking up the pronunciation there are two acceptable ways to say it: ˈtran(t)-sh(ē-)ənt; ˈtran-zē-ənt. I always used the “Z” when saying transient. That announcer sounds very professional and an articulate speaker. Learn something new every day. Both the 911 envelope and 912 envelope follower could be thought of as transient generators.
The 913 Triggered Envelope Generator may be a little more than just a pair of Schmitt triggers. But here is the mystery module that seemed to fit that 913 description.
Only has those Dymo lables, and the top of the description fell off. But reads XXXXXXX generator
The 1965 price of $150 would indicate a little more circuitry involved than just Schmitt triggers. The 912 with envelope follower and Schmitt trigger was only $100. Not sure the exact function, difficult to tell. The two “scale” dials may indicate the module would output some type of CV or a fixed CV set by the dial? Or the “scale” dial could be the piont where the control signal produces an S-trigger? Would like to know a little more about that module, but seems intended to interface outboard gear to trigger the modular. Something that would be more usefull in a 1965/66 studio then it might be today.
A transient generator is the same thing as an envelope generator. On a Serge Synthesizer, the Dual Transient Generator is primarily an ASR type envelope generator (as well as a sub-harmonic generator, envelope detector, LFO, audio oscillator, low-pass filter etc…)
Stephen
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