This amp has been used on various tours and has a lot of cosmetic damage. Please see photos for reference. Everything functions as intended. PLEASE NOTE: This amp is sold as-is and therefore not covered under manufacture warranty. For years, bassists have been combining guitar and bass amps to remarkable effect, adding harmonics and layers of overdrive from a guitar amp to their core bass tone in pursuit of the ultimate live sound. This “bi-amp” trend got us thinking: why drag two amps to the show when you could take just one? The result is the OB1 series of Class A/B rack mountable bass heads, which take care of this and much more besides. The key to the OB1’s unique sound is our footswitchable blend circuit, which adds a veneer of controllable gain and increased harmonic content to the upper registers of the input signal. The lower frequencies and clean signal are left alone, staying just as warm and clear as they would in a “bi-amped” setup. Depending on where the Gain and Blend controls are set, the possibilities are limitless. Toggle the Blend control to achieve anything from a transparent clean boost to all-out filthy grind and everywhere in between. OB1-300 is the 300-Watt version, sharing the same features and 2U rack dimensions as the more powerful OB1-500.