Rocktron Boutique Series Sacred Fire Compressor Gain, Threshold, and Sacred Fire (compression) controls Sacred Fire will provide automatic gain control to keep the volume of the note(s) at a constant level You can achieve lush and richer sounds when combining the Sacred Fire with other effects such as chorus and flanger When playing chords without distortion (clean), the sustain control helps all the strings become clearer and more distinct while the overall sound will ring with a similar volume level Power supply not included