A lot of amp manufacturers call their Treble/Mid/Bass knobs ketone controls. Bugera calls theirs "EQ" because they spent a lot of time making sure that they each have a unique character. Treble really screams; Mid puts you about six rows into the audience; Low can add more growl than an angry Kodiak bear. The Presence control is tailored to smooth out your tone or add enough bite to cut through any cymbal. It can bring new life to darker sounding instruments. This is a closeout model, and does not feature Infinium technology.