The 528E is a complete, self-contained voice processor, that performs six separate functions. In addition to a microphone preamp, the unit performs de-essing, compression/limiting (with sidechain input), downward expansion, voice symmetry alignment and the signal can be sculpted with parametric EQ. All six processors may be used simultaneously, and although the unit is referred to as a "voice processor" it is perfectly suitable for any signal.

Each function features a full complement of controls in an easy-to-use layout. Separate LED meters monitor microphone gain and dynamics gain reduction functions. The 528E works with any professional microphone. The preamp's gain is variable up to 60dB, and 48-volt phantom power is provided for use with condenser microphones. The de-esser senses and regulates selectable high frequencies to reduce or eliminate annoying sibilance and "lip smacking".

The compressor/limiter maintains uniform levels while the downward expander eliminates "pumping," "breathing," and noise build up. Because it's program controlled, the unit's dynamic range processor responds quickly to transients. The three band parametric EQ performs both creative and corrective operations, with bandwidth variable from 1/3 octave to 4 octaves, 15 dB boost/cut, and overlapping frequency ranges. The voice symmetry switch of the 528E corrects for excessive positive or negative signal peaks of the human voice. A simple in/out switch controls this function.