A driver amplifier operative from a single DC voltage supply, coupled directly to the output load without the need for DC coupling capacitors used for preventing DC reaching the output load. An onboard power supply generates a negative voltage rail that powers the output amplifiers, allowing driver amplifier operation from both positive and negative rails. Since the amplifiers can be biased at ground potential (0 volts), no significant DC voltage exists across the load and the need for DC coupling capacitors is eliminated.