Delay, Echo, Reverb, Chorus

Delay is defined as the duplicating of a signal  and reintroducing it, usually after a slight "delay", to the orginal signal.  U2's The Edge uses this effect often. Check out "I Still Haven't Found What I Am Looking For"

 

Reverb is the short echo you hear in a large room in which the regenerations are randomly dispersed.  Effect wise reverb was initially created using large plates of metal  (plate reverb) that didn't sound natural but sounded cool. Plate reverb was often used in the recordings of the 50's by such artists as Buddy Holly and Gene Vincent. Check out the more recent Ravonettes for some cool plate reverb. Other reverbs are digital simulations of various size room reverbs.

 

Chorus is the effect of several musicians playing simultaneously.  A chorus reproduces this effect including the slight timing variations inherent in several people playing simultaneously. The effect adds a lushness or fullness to your sound.