Propellerhead Reason - 4.0 Instrukcja Operacji Pobierz pdf (Strona 196)

SUBTRACTOR SYNTHESIZER

194

Envelopes - General

Envelope generators are used to control several important sound parameters in ana-

log synthesizers, such as pitch, volume, filter frequency etc. Envelopes govern how

these parameters should respond over time - from the moment a note is struck to the

moment it is released.

Standard synthesizer envelope generators have four parameters; Attack, Decay, Sus-

tain and Release (ADSR).

There are three envelope generators in the Subtractor, one for volume, one for the Fil-

ter 1 frequency, and one modulation envelope which has selectable modulation desti-

nations.

The ADSR envelope parameters.

Attack

When you play a note on your keyboard, the envelope is triggered. This means it

starts rising from zero to the maximum value. How long this should take, depends on

the Attack setting. If the Attack is set to “0”, the maximum value is reached instantly. If

this value is raised, it will take time before the maximum value is reached.

For example, if the Attack value is raised and the envelope is controlling the filter fre-

quency, the filter frequency will gradually rise up to a point each time a key is pressed,

like an “auto-wha” effect.

Decay

After the maximum value has been reached, the value starts to drop. How long this

should take is governed by the Decay parameter.

If you wanted to emulate the volume envelope of a note played on a piano for example,

the Attack should be set to “0” and the Decay parameter should be set to a medium

value, so that the volume gradually decreases down to silence, even if you keep hold-

ing the key down. Should you want the decay to drop to some other value than zero,

you use the Sustain parameter.

Sustain

The Sustain parameter determines the level the envelope should rest at, after the De-

cay. If you set Sustain to full level, the Decay setting is of no importance since the vol-

ume of the sound is never lowered.

If you wanted to emulate the volume envelope of an organ, you theoretically only really

need to use the Sustain parameter set to full level, as a basic organ volume envelope

instantly goes to the maximum level (Attack “0”) and stays there (Decay “0”), until the

key is released and the sound instantly stops (Release “0”).

But often a combination of Decay and Sustain is used to generate envelopes that rise

up to the maximum value, then gradually decreases to finally land to rest on a level

somewhere in-between zero and maximum. Note that Sustain represents a level,

whereas the other envelope parameters represent times.

Release

Finally, we have the Release parameter. This works just like the Decay parameter, ex-

cept it determines the time it takes for the value to fall back to zero after releasing the

key.

Amplitude Envelope

The Amplitude Envelope is used to adjust how the volume of the sound should

change from the time you press a key until the key is released. By setting up a volume

envelope you sculpt the sound’s basic shape with the four Amplitude Envelope pa-

rameters, Attack, Decay, Sustain and Release. This determines the basic character of

the sound (soft, long, short etc.).

Filter Envelope

The Filter Envelope affects the Filter 1 Frequency parameter. By setting up a filter en-

velope you control the how the filter frequency should change over time with the four

Filter Envelope parameters, Attack, Decay, Sustain and Release.

Attack

(time)

Decay

(time)

Sustain

(level)

Release

(time)

Key Down

Key Up

Level

Time

1 2 ... 191 192 193 194 195 196 197 198 199 200 201 ... 401 402

Komentarze do niniejszej Instrukcji

Brak uwag

Propellerhead Reason - 4.0 Instrukcja Operacji Strona 196

Komentarze do niniejszej Instrukcji

Powiązane produkty i podręczniki dla Oprogramowanie Propellerhead Reason - 4.0