(1) CONTROL SECTION: Operation and principles ^
1 - 3 Envelope Modifiers (EM)
Figure 6 - Envelope Modifiers
1-3 ENVELOPE MODIFIERS (EM)
This section establishes the changes in volume over time when a key is pressed and released.
With all controls at the normal setting, slowly turn the Attack knob clockwise while playing a note on the keyboard. Note the change the attack time (or rise time) of the sound. Now set the Attack, Sustain, and Decay knobs all to the "0" position, then play a key and notice how quickly the sound is cut off. Next, try gradually turning up the decay time and note how the sound takes longer and longer to fall in volume. With Attack at "0" and Decay at "0", turn up the Sustain level a little at a time. Note how this increases the volume that is sustained after the sudden decay time. A switch used to select the length of the final release time of the sound once the key is released. To understand what effect this has, set Attack at "0", Decay at "10", and Sustain at "10". Then play a note and change switch positions.
Last but not least we come to the Hold switch. When this switch is ON, all EM controls with the exception of the Attack knob are disconnected (the settings will have no effect on the sound). Turn the Attack time up to "10" and turn on the Hold switch. Then press a number of keys one after the other leaving a small space between each. After a few seconds the sound of those keys will become audible one at a time in the same order in which you just played them. When you wish to use the Hold switch, always keep in mind that it will have no effect if the Attack level is below "7".
In order to release the Hold function, the Attack level must be turned down to below "3" at the same time the Hold switch is turned off. Repeat this operation a number of times so that it comes naturally.
Figure 7 - Release time settings
* With the Hold switch ON (and the attack time above "7"), if you press the same key a second time, it acts to release the hold effect for that note. (Don't confuse this action with a malfunction of the synthesizer.)
The envelope generator is a device that generates a DC voltage signal that varies in strength in accordance with the settings of the Attack, Decay, Sustain, and Release controls when a key is played.
Since this output signal controls the VCA (Voltage Controlled Amplifier), the result is a signal that varies in volume over time. When the same envelope generator output voltage signal is used to vary the cut off frequency of the VCF, the result is called the Expand effect and its intensity is controlled by the D LPF section Expand knob.
Since there is actually one EG and VCA built into the PS-3100 for each and every key in the keyboard, you can obtain the desired output signal as determined by the EG settings even when playing a number of keys in succession.
By the same token, there is a separate VCF for each key thus permitting the use of the Expand effect when and where desired.