Cranborne Audio Carnaby 500 Harmonic EQ

The Cranborne Audio Carnaby 500 is a 3-band parametric EQ for the 500 Series format built around a genuinely new circuit concept: the Harmonic EQ™. Rather than boosting or cutting frequency content by filtering in the conventional sense, the Carnaby 500 uses harmonic saturation as its primary mechanism — each band generates controlled harmonic distortion around the target frequency, which the ear perceives as a boost or cut. The result behaves like an EQ on the spectrum analyser but sounds like analogue saturation in practice, adding texture and density that passive and active filter designs cannot replicate.

Three bands each cover a distinct range with a saturation character tailored to that frequency region. The HI band is a shelving filter sweepable from 5 kHz to 25 kHz, using smooth saturation to naturally extend high-frequency content beyond the audio band — adding air and breath to vocals and acoustic instruments without harshness. The MID band is a fixed-Q peaking filter covering 200 Hz to 6.2 kHz, using harmonic emphasis to add presence and body anywhere in the midrange. The LO band is a shelving filter from 20 Hz to 420 Hz that applies hard-clipping saturation to extend sub-harmonic frequencies into the audible low end, delivering anything from subtle warming to full sub-harmonic saturation depending on drive level. All three bands are overlapping and interactive, and each generates approximately 8–12% THD+N at typical operating levels — figures that are features rather than flaws.

A key characteristic of the Carnaby 500 is its dynamic response: both boost/cut depth and harmonic content increase as the signal drives the circuit harder. The ±20 dB input and output trim controls let you push the input for more saturation and drive, or attenuate it for a cleaner EQ response from the same hardware. Maximum input and output levels reach +26 dBu at under 0.003% THD in clean operation. Two units link wirelessly via Cranborne’s OptoSync LED-to-optical system for stereo operation — all controls synchronise from master to slave with no cables, with automatic circuit calibration ensuring matched harmonic characteristics across units.