Keeley DS-9 is a unique distortion pedal combining the best of the famous green and orange stompboxes from the past, now adding a bass boost for zero loss of low frequencies. Level controls the amountThe DynaTrem Dynamic Tremolo by Keeley Engineering is an all new type of tremolo that is dynamic and responsive to your playing. Your playing controls the Rate and Depth. The harder you play, the more it responds. Play softly and it relaxes. Set the sensitivity with Rate or Depth controls and you have an unparalleled ability to be expressive with your guitar and tremolo.