The HA-6AB headphone/monitor amplifier is a unique combination of a headphone amplifier, and a conventional power amplifier. This combination of functions can save the expense of an extra power amplifier in many recording studios. The unit is an economical 20 watt per channel stereo amplifier, but unlike a conventional power amplifier, it has six headphone outputs on the front panel, each with a volume control.

When using the HA-6AB for overdubbing or rehearsal, the amplifier provides more than adequate power for headphones, even older low-impedance models, and allows each musician to set their own volume level. When overdubbing is complete, the unit can power tape playback through either or both of two sets of speakers, selectable from front panel pushbuttons.

The HA-6AB features an input level control on the front panel, and a pair of yellow LED's light up whenever signal is present, while another pair of red LED's show any overload conditions in either channel. While most headphone amplifiers provide half a watt or less per headphone channel, the unit's higher power can drive headphones of any impedance to their full rated listening level, and do so with minimal noise and distortion. Its power capacity is also just right for the small "cube" reference speakers used in most recording studios as a comparison with the main control room monitors.

Additional remote stations can be daisy chained to the main unit. The HA-6AB utilizes an efficient toroidal power transformer for silent operation and low magnetic leakage, as required in a studio environment. It is fully protected against thermal overload, and can withstand a short circuit on any or all outputs for an indefinite time without damage.