User Manual

OB-6 Operation Manual

Filter Envelope

Attack: Sets the attack time of the envelope. The higher the setting, the

slower the attack time and the longer it takes for the lter to open from

the level set with the lter frequency knob to the level set by the lter

envelope amount. Percussive sounds typically have sharp (short) attacks.

Decay: Sets the decay time of the envelope. After a sound reaches the

lter frequency set at its attack stage,

decay controls how quickly the

lter then transitions to the cutoff frequency set with the sustain knob.

The higher the setting, the longer the decay. Percussive sounds, such as

synth bass, typically have shorter decays (and a generous amount of low-

pass lter resonance).

Sustain: Sets the lter cutoff frequency for the sustained portion of the

sound. The sound will stay at this lter frequency for as long as a note is

held on the keyboard.

Release: Sets the release time of the envelope. This controls how

quickly the lter closes after a note is released.

Velocity: on, off—When enabled, allows key velocity to inuence lter

frequency. If the amount is set to a positive value in low-pass lter

mode, the harder you play, the more the lter will open and the brighter

the sound will be. Conversely, if the amount is set to a negative value,

the harder you play, the more the lter will close and the less bright the

sound will be. This control makes for more touch-sensitive sounds

Amount: Sets the amount of modulation from the lter envelope to the

lter. Higher amounts more dramatically affect the cutoff frequency. This

control is bipolar. Positive settings produce standard behavior. Negative

settings invert the envelope.

The description of envelope behavior above is true when the amount parameter

is set to a positive value. But since this control is actually bi-polar, it is possible to set

a negative amount of modulation. In this case, the envelopes are inverted and their

behavior changes. The best way to get a feel for the difference is to experiment with

both positive and negative settings of the envelope amount parameter.

The cutoff frequency setting may limit the effect of the envelope on the lter. For

example, in low-pass lter mode , if frequency is at its highest setting, a positive enve-

lope amount will have no effect on the lter since the lter is already completely open.