Instruō - cèis [2] Overview

video upload by Instruō

"The Instruō cèis[2] is a fully analogue voltage controlled ADSR envelope generator. The ADSR function generator is the model pioneered by the East-coast mindset and is extensively used in subtractive synthesis patches. The cèis[2] gives the ability to externally control the attack, decay, sustain, and release stages of the envelope while also emitting trigger and gate signals for each segment, offering maximum versatility from a classic tool.
This version [2] revision brings additional flexibility and control through a completely redesigned logic extraction circuit for the segment gates, envelope re-trigger input, and a precision throughput for voltage controlled slew limiter capabilities.

• LED button for manual control and indication of output CV level
• Fader and CV control over all 4 segments
• Gate output per segment
• Fader LED for segment stage indication
• Gate/Trig modes which can force completion of the Attack duration when triggered
• Hold mode for sustain segment lock for CV slew use
• Combined trigger output which fires when there is a change in segment
• Variable envelope response shape from linear to exponential

Instruōduction 00:00:00
What's new? 00:00:54
TRIG|GATE|HOLD 00:01:27
Trigger and RETRIG 00:02:08
New logic extraction circuitry 00:02:46
CV controlled slew 00:03:05
What's to come in this video 00:03:23

Subtractive Synthesis Synopsis-is: A.D.S.R Fundamentals 00:04:02
Audio Signal Path 00:05:56
Keyboard Control 00:08:32
Basic amplitude gating 00:10:19
Gate to ADSR to amplitude 00:11:48
The traditional ADSR 00:12:30
Gate following 00:13:59
Control signal path for timbre 00:16:53
A classic subtractive patch 00:19:06
Decay/Release gate controlled 00:20:23
Completing the keyboard control (RETRIG) 00:22:02
cèis[2] upgrades 00:25:29
Patch polishing 00:26:29

Rhythmic control and percussion patching 00:30:48
Enveloped resonant filter Kick voice 00:31:16
Decay time CV 00:35:52
Noise pulse percussion 00:37:27
Linear/Exponential 00:39:25
Sequencing and envelope 00:40:09
Adding a synth voice 00:40:46
Adding rhythmic complexity 00:42:49
Trigger delay 00:43:27
Trigger burst generator 00:46:08

CV controlled SLEW 00:50:02
Attack - Rise / Decay - Fall 00:52:33
Slew slew for logic extraction 00:54:24
Melodic interval logic extraction 00:55:36
Manual melody interval logic extraction 00:57:15
Sequenced melody interval logic extraction 00:58:34
Rise/Fall independent logic output 00:59:59

Audio rate waveshaping 01:01:58
Signal throughput configuration 01:02:43
Square to triangle conversion 01:03:24
Negative CV range extension 01:04:26
Logic as comparator for PWM 01:06:05
CV controlled PWM 01:07:34
Envelope as a LPF? 01:08:30

Expanded control methods 01:09:54
Parallel envelope generation and logic 01:10:21"