APPLIED ACOUSTICS SYSTEMS ULTRA ANALOG Uživatelský manuál stáhnout pdf (Strana 42)

4.7 The Envelope Module 42

The envelope modules generate a four segment envelope: attack, decay, sustain, release. The

attack time is adjusted using the A knob. The attack time can also be modulated with the velocity

signal received from the Keyboard in such a way that that the higher the velocity signal the shorter

the attack time will be, the intensity of this effect being controlled using the V slider on the left

of the A knob. When the slider is in its lower position, the attack is only determined by the value

of the A knob, increasing the value of V will increase the inﬂuence of the velocity signal until the

attack time is strictly determined by the inverse of the velocity signal when V reaches its maximum

value. The decay time is set with the D knob. The sustain phase of the envelope generator lasts

from the end of the decay phase until the key is released. When the S knob is fully turned to the

left, the sustain level is zero and there is no sustain phase while fully turned to the right, the sustain

level is at maximum and there is no decay phase. When the key is released, the envelope generator

toggles to the release phase and the envelope signal will decrease from the value at the end of the

sustain phase to zero in a time set by the R knob.

Note that during the sustain phase, the envelope signal can be made to decrease even if a key

is still depressed. The time taken to go from the level set by the S knob to a value of zero is

then determined by the value of the Time knob located to the right of the S knob. When the Time

knob is fully turned to the left, the envelope signal will fall to zero right after the end of the decay

phase when the knob is in it rightmost position, the sustain level will be held as long as the key is

depressed. Finally, the overall level of the envelope can be controlled with the velocity signal from

the keyboard through the V slider located to the left of the S knob and behaves in exactly the same

way as the V slider located near the A knob.

4.7.1 Shape of the Envelope Segments

We have so far determined the shape of the envelope by adjusting the duration of the different

phases as well as their level. The envelope signal can further be modiﬁed by adjusting the shape of

the envelope segments which can be set to linear or exponential as shown in Figure 19. The shape

is selected with the Slope drop-down menu.

4.7.2 Free Run Mode

The Free button sets the envelope into free-run mode. This allows one to bypass the sustain phase

of the envelope or in other words, to go directly from the decay phase to the release phase regardless

of the amount of time a key is depressed.

4.7.3 Legato Mode

This mode is used to choose how the envelope generator reacts when a new note is played before

the end of the preceding one. When this occurs, two strategies are possible. The ﬁrst one consists

in triggering a new envelope, from the attack phase, when the new note is played. The second

consists in applying the current envelope signal of the ﬁrst note to the second note which produces

1 2 ... 37 38 39 40 41 42 43 44 45 46 47 ... 69 70

Žádné komentáře

APPLIED ACOUSTICS SYSTEMS ULTRA ANALOG Uživatelský manuál Strana 42