Nikko EQ-500 6-Band Stereo Graphic Equalizer Made in Japan

Nikko EQ-500 6-Band Stereo Graphic Equalizer Made in Japan

A practical, well-specified six-band stereo graphic equalizer from Nikko Electric of Tokyo, the EQ-500 delivers honest frequency shaping with excellent measured performance in a functional black finish — in fair cosmetic condition and fully working.

The Nikko EQ-500 is the natural companion to Nikko’s 1980s receiver lineup, sharing the same six-band equalizer frequencies and circuit topology as the EQ-II but in an updated cabinet design. Each channel provides slider controls at 40 Hz, 125 Hz, 400 Hz, 1.25 kHz, 4 kHz, and 12.5 kHz with ±12 dB of cut or boost in 2 dB steps — precise enough for meaningful room correction and system tailoring. The measured specifications are strong: 0.01% THD, better than 100 dB signal-to-noise ratio, and a frequency response from 10 Hz to 30 kHz, ensuring the EQ contributes no audible colouration of its own. A bypass switch allows instant before/after comparison, and a pre/post EQ tape switching facility adds flexibility for cassette or reel-to-reel integration.

Key Specifications:

Type: Stereo graphic equalizer

Bands: 6 bands per channel at 40, 125, 400, 1,250, 4,000, 12,500 Hz

Control range: ±12 dB per band (2 dB steps)

Frequency response: 10 Hz – 30,000 Hz

Total harmonic distortion: 0.01%

Signal-to-noise ratio: >100 dB

Input impedance: 80 ohms

Features: Bypass switch, pre/post EQ tape switch

Years of manufacture: 1981 / 1985–1987

Country of manufacture: Japan

Finish: Black

Condition: Fair cosmetic condition, fully tested and working

Dimensions: (Width x Height x Depth) 440 x 96 x 329 mm (17.3 x 3.8 x 13.0 inches)

Weight: 4.1 kg (9 lbs)

Made in Japan, this Nikko EQ-500 is a solid, practical six-band graphic equalizer that gets the job done with excellent specifications and honest sound — a sensible and affordable choice for anyone looking to add frequency control to their vintage or modern system.

Backed by Radique Audio’s 90-day warranty and our perpetual trade-back policy, you can purchase with confidence; asking $125.