Boss | SP-1 Spectrum Equalizer

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Model Number or Name:

SP-1 Spectrum Equalizer

Discontinued
Equalization

Original Price: $95

Excellent Used Price: $475

Year Released: 1977

Year Discontinued: 1981

Alternate Version(s)

No Alternate Versions Listed

The SP-1 is a parametric equalizer with one frequency band only. The spectrum knob sets the frequency range in the interval 500Hz to 5kHz. The balance knob sets the peak within the range. The SP-1 was more popular with keyboard players than with guitar players. Today it is one of the most sought after collectors items and a mint condition SP-1 doesn’t come cheap.

Version Differences

The first models featured the clear plastic switch and immediate LED as well as the silver thumb screw. The switch was later changed to black, the LED was made permanent and the black thumb screw was the last change made before it was discontinued 1981.