Orange OB1-500 Bass Head - UsedOB1 500 shares the same layout and 2U rack dimensions as the less powerful OB1 300, coupled to a full fat 500 Watt output section to move some serious air. The OB1 splits the input instrument signal into two separate paths. One side amplifies the clean signal, with all the clarity you would expect from Orange. The other adds stages of gain to the upper harmonics only, controllable via the amps Gain knob. These two elements are combined using the