The Quattro, as the name suggests, is a four mode delay: COPY / ANALOG / MODULATION / FILTERED. The maximum is exactly 958.3 ms, COPY is the standard digital delay sound, where the echo sounds as close to the original as possible. ANALOG sounds like the classic BBD effect, where the delay sounds degraded with less high frequencies and a lot more smear in the sound. MODULATION adds a chorusing effect to your delays and makes them wider and deeper. This is amazing for spacy clean sounds. FILTERED mode send your guitar through an adjustable Mid-Frequency filter before it gets delayed. This mode presents many interesting possibilities and you just won’t believe it is all coming out of a tiny little pedal.