Roland SC-88 Pro Envelope, ❍Resonance: -64— +63, ❍Decay Time: -64— +63, ❍Attack Time: -64— +63, ❍Release Time: -64— +63, ❍Cutoff Freq (Cutoff Frequency): -64— +63

❍Cutoff Freq (Cutoff Frequency): -64 — +63

Positive settings of Cutoff Freq will raise the cutoff fre- quency. Negative settings will lower the cutoff frequen- cy. As you set this value higher in the positive direc- tion, more overtones will be allowed to pass, and the sound will become harder (brighter). The further this value is set in the negative direction, the fewer over- tones will be allowed to pass, and the sound will become softer (darker).

*For some sounds, positive (+) settings of Cutoff Freq will cause no noticeable change in the sound.

Low pass filter characteristics

Level

Frequency

Cutoff frequency

❍Resonance: -64 — +63

When the Resonance value is increased, the overtones in the area of the cutoff frequency will be emphasized, creating a sound with a strong character.

*For some sounds, negative (-) settings of Resonance will cause no noticeable change in the sound.

Level

Frequency

Cutoff frequency

Low High

Resonance

Envelope

The volume of an instrument changes with time, from the moment the note begins to sound to when it disap- pears. This change can be indicated on a graph as shown in the following diagram. This shape is unique to each instrument, and is an important element in how we distinguish sounds we hear. This shape is called the “envelope.” The envelopes of musical instrument sounds can change depending on how the instrument is played. For example if a trumpet is played sharply and strongly, the attack will be quick and the sound will be sharp. But if a trumpet is played lightly and softly,

A : Attack time

Cutoff frequencyD : Decay time R : Release time

Filter				Envelope			Sound ends
								Time
Level
		A	D				R
		-on			Note	-off
	Note

❍Attack Time: -64 — +63

This parameter adjusts the sharpness of the beginning of the sound.

❍Decay Time: -64 — +63

This parameter adjusts the time over which the sound will fall from the highest point of the attack down to the sustain level (Fig.1).

*Some sounds have a sustain level of 0 (Fig.2). Piano and guitar sounds are in this category.

❍Release Time: -64 — +63

This parameter adjusts the time over which the sound will decay after the note is released until it is no longer heard. The cutoff frequency will also fall according to this.

*For some sound, modifying the various Time settings of the envelope will cause no noticeable change in the sound.

Fig.1

Volume

Sounds ends

			Sustain Level
					Time
	A	D		R
Note-on			Note-off

Fig.2

A : Attack time

VolumeD : Decay time

the attack will be softer. In order to adjust the attack of a sound, we can modify the Attack Time of the enve- lope. By modifying the values of the envelope we can simulate the characteristics of many different instru- ments.

The envelope shape that we create in this way will

Sounds ends

AD

R : Release time

Time

also affect the way in which the cutoff frequency changes. If the cutoff frequency had been lowered, it will rise as the envelope rises, and will fall as the envelope falls.

Note-on Note-off

Chapter 2. Parts and paramters 33