Defined by a 5ms. delay with 25% feedback with modulating changes in pitch.

Remember the difference between Vibrato and Tremelo!
Tremelo chages in volume, has 100 depth and is modulation dependent.

40 – 120ms with low feedback and no modulation.  This is shorter than an “Echo” delay and is sometimes called a “Supertight” delay.  This emulates a room with a wall parallel to the sound source.  You hear this most in the real world when doing sound check on a snare drum in an empty club with a flat concrete back wall.  The snare hits, then you hear the “Slapback” from the wall right after.