Serial number 0757 Features The original version of the Xotic Effects BB-PREAMP, featured warm, compressed overdrive tone. However, for some guitarist there was too much compression that perhaps restricted the pedal from "breathing". A new version (serial number 3643 and higher) was released with some of the compression reduced in April 2007. The result was a more aggressive BB-PREAMP that today remains one of our best selling pedals.