Dual ADSR

Dual Transient Generator (DTG)
The DUAL TRANSIENT GENERATOR (DTG) provides two independent outputs with voltage controllable rise and fall times. This module is identical to the Dual Universal Slope Generator except that it does not have all of the front panel features. This module is a useful, space-effective unit to be used for many of the same functions as the Dual Universal Slope Generator. Common uses of the Dual Transient Generator are for simple “AR”-type envelope generation, as a dual voltage-controlled low frequency oscillator, or as a voltage-controlled clock (especially suitable for clocking the Touch Keyboard Sequencer or any of the Sequencer Programmers). These functions can be patched with the Dual Universal Slope Generator, but since many of the features are left unused in these patches, the Dual Transient Generator provides the same function while using less front Panel space.

Dual Comparator (COM)
The DUAL COMPARATOR (COM) provides several often useful house-keeping functions within the Serge system:

• Logical Decisions: If the + input is greater than the - input, then the output will be high. If not, then the output will be low. 
• Level Detection. A pulse will be generated whenever an input voltage reaches a pre-set threshold. For example, when an envelope detector reaches a certain loudness level, it can be used with the Comparator to generate a pulse to activate or de-activate other events programmed within the synthesizer. 
• Voltage variable pulse width modulation of any of the Serge oscillators. 
• “Squaring” audio signals, whereby frequency related pulses are derived from an input signal. These pulses can be used for frequency sub-division (via a Dual Slope Generator or Sequencer), or as raw audio, rich in harmonic content. 

In addition to the +/- inputs, each of the Comparators include a front-panel knob to manually set a threshold.

Dual Extended Envelope Generators (ADSR)
The EXTENDED ADSR (ADSR) is a complex envelope generator using the four segment envelope normally encountered in keyboard synthesizers. This ADSR, however, is designed with extra features such as voltage control of each section, an initial voltage controllable delay time, switchable slopes, and a master voltage control. Each segment may be manually set and voltage controlled, so the module may be used with or without keyboards as a versatile, programmable control voltage generator. In addition to the normal Attack, Decay, Sustain, and Release segments, an Initial Delay time is included. This allows multiple envelopes to be initiated from a single trigger or gate, delayed with respect to one another. Ramps for the Attack and Release segments can be switched to either linear or exponential slopes with the three-position switch. In the left [i.e. top] position, the Attack will have an exponential slope. In the middle position, both the Attack and Release will have an exponential slope, and in the right [i.e. bottom] position, all will have linear slopes. A master 1V/OCT control will control all slope times to allow such effects as decreasing the entire envelope time as the pitch of an associated oscillator increases. This phenomenon is typical of many acoustic instrument envelopes.