The Dyna Comp Compressor can tighten up your signal, add rich sustain or create the percussive and clicky sound heard on numerous hit records. The Dyna Comp Compressor is one of the most popular compressors of all time. Whether you want to tighten up your signal, add rich sustain or create the percussive and clicky sound heard on numerous hit records, this pedal is straightforward and easy to use. For these reasons, the Dyna Comp Compressor has been the secret weapon on countless pedalboards for years. The Dyna Comp is powered by one 9-volt battery (remove bottom plate to install), a 9-volt AC adapter such as the Dunlop ECB003/ECB003E or a DC Brick power supply.