The ECHO 600 DARK is a uniquely voiced analog delay that produces a dense, rich sound with infinite feedback. This pedal has an amazing sound! Pedal now out of production, highly sought after and nowhere to be found! The controls are very simple: - The first adjust the delay time which can be set up to 600 milliseconds - the second adjusts the volume of the repetitions with respect to the original signal. - the third regulates the number of repetitions. With one switch you can switch from a true-bypass signal, to a buffered signal that fades the delay tail after the effect is deactivated, a second switch adjusts whether the repeats will have a brighter or a darker sound. It is also an internal TRIM adjusts the gain of the signal. An expression pedal can be connected to adjust the amount of repetitions. It has a mono and a stereo output. A must have! One of the best analog delays ever. In excellent aesthetic condition and fully functional!