Harrison 500-Series MR3 EQ

Harrison 500-Series MR3 EQ

The Harrison 500-Series MR3 EQ brings the distinctive equalizer design of Harrison’s MR3 recording console into a compact 500 Series module. Originally developed for the Music Recording 3 console introduced in the early 1980s, the circuit is designed to combine precise frequency control with the broad, musical tonal shaping associated with classic Harrison analog consoles.

The three-band parametric section provides ±10 dB of boost or cut across each band. The high-frequency section covers 800 Hz to 15 kHz and operates as a 6 dB/octave shelf that can be switched to a second-order bell response with proportional Q. The low-frequency section covers 40 Hz to 800 Hz and provides similar shelf-to-bell flexibility. A fully parametric midrange band covers 400 Hz to 8 kHz with continuously variable proportional Q, allowing anything from broad tonal adjustments to more focused corrective EQ.

A separate high-pass filter covers 25 Hz to 3.1 kHz with a 12 dB/octave slope. Independent bypass switches for the EQ and filter sections make it easy to audition processing separately, while an input overload indicator assists with gain staging.

• Harrison MR3 console-inspired analog EQ
• Three-band parametric equalizer
• ±10 dB boost and cut range
• High-frequency range from 800 Hz to 15 kHz
• Low-frequency range from 40 Hz to 800 Hz
• Midrange frequency range from 400 Hz to 8 kHz
• Switchable shelf and bell response on high and low bands
• Harrison proportional-Q response
• Continuously variable Q on the midrange band
• High-pass filter from 25 Hz to 3.1 kHz
• 12 dB/octave high-pass filter slope
• Separate EQ and filter bypass controls
• Input overload LED
• Standard 500 Series format