This is regarded by many as the best graphic equalizer ever produced. It was originally bought for $600 and probably would cost over a $1,000 to buy new these days. What can you do with the SS-525X that you simply can't do with today's cheaper equalizers?
+ Calibrate your stereo. The SS-525X comes with a serial number matched and calibrated microphone that you position where you sit. The equalizer will listen to a pink noise tone it sends through your speakers to figure out which frequencies your stereo and listening room are subtly shifting during playback. The onboard computer then calculates the exact equalizer curve to compensate for the shift giving you perfectly natural music at your listening position. (Older equalizers can neither analyze room dynamics nor calculate the required EQ curves to calibrate a stereo).
+ Use digital EQ controls instead of manual EQ sliders. (Cheaper equalizers use flimsy sliders that always attract dust, look outdated, and often have missing knobs).
+ Fine-tune your stereo sound in 12 frequency bands and separately in each channel. (Most cheap equalizers control only 5 or 7 frequency bands max and often in both channels instead of independently).
+ Save up to four customized digital equalizer curves in memory. Then switch curves instantly with a remote control whenever you want your optimal custom presets for Rock, Jazz, Pop, or Classical music. (Cheap equalizers with manual sliders can only hold one curve at a time and must be moved each time, one slider at a time, so difficult it's almost never done).
+ Enjoy watching the music play back on a professional spectrum analyzer. (Most of today's equalizers have no spectrum analyzer at all and if they do it's a tiny little LED display that looks best switched "off").
As you can see from the pics below this SS-525X is in mint condition. It even comes with its original box, ADC calibrated microphone, remote control, and instruction manual. It's yours for $350 plus whatever FedEx Ground shipping and insurance cost. I'm in the Bay Area of California just in case somone local is interested in it.