Orange OB1-500 - 500 watt Bass Amp HeadThe key to the OB1s 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 warm and clear just as they would be in a bi amped setup. Depending on where the Gain and Blend controls are set, the possibilities are limitless. Punch in the Blend control to achieve anything from a