True Stereo Delay With Trex's "REPLAY BOX", everything starts with the twin INs and OUTs, which give you 3 setup options: mono in/ mono out (using the left INPUT and OUTPUT jacks; mono in/stereo out (using the left INPUT jack and both OUPUTS; and stereo in/out using all 4 jacks. Running in full stereo, "REPLAY BOX" is really two separate delays in one. The main controls on your "REPLAY BOX" are as follows.VOLUME: sets the unit’s overall volume output, while Two delays in one MIX: lets you set the balance of your dry and delayed signals. REPEAT: controls the number of delay repetitions. TEMPO: lets you move from a quick slapback echo to an almost eternal 3-second delay. NOTE DIVIDER: switch to chooses between a quarter note, a quarter note triplet, and a dotted eight note delay rhythm.