Boss DD-7 - Reverse Playback Delay Setting; Room Ambience Sound Setting; Doubling Effect Setting; Trick Sound Setting

Setting Samples
22
Reverse Playback Delay
This delay gives an eect somewhat similar to reverse playback. It’s
a sound that’s just a little out of the ordinary.
Doubling
This provides an eect similar to the sound of two guitars layered
together
Room Ambience Sound
This delay simulates the sound that would be picked up by an
ambience mic located on a stand within the room.
Trick Sound
Employs repetitions of delayed sound to create an oscillating sound.
Unique eects can be obtained by adjusting the D.TIME knob.
* Care should be taken, since this eect tends to increase the
volume.