At auction is a Pioneer piece that made history in the 1990s being at the first place of many specialised magazines of the top Hi Fi field. PIONEER GR-551 - rare 7-band stereo graphic equalizer Spectrum Analizer Equaliser - 1990s In good overall and working condition, very well kept (look at the photo gallery). Completely functional and checked by an audio workshop in Milan. 7 adjustment bands per each channel: 60 Hz, 150 Hz, 400 Hz, 1 kHz, 2.4 kHz, 6 kHz, 15 kHz with Spectrum analysers for both channels. Perfectly functional and in excellent aesthetic condition. We only use anti-shock and anti-breakage material for the shipment and I will also provide a small insurance to avoid any damage.