Tag Archives: Active Equalizer

Bose® 901 Series II #114658 Repair

From Rain City Audio: This Bose® 901 Series II Active Equalizer, #114658, just came through the shop for repair. It had stopped performing the proper equalizer functions, and so was time for an overhaul. Inside, it looks like the smaller … Continue reading

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Bose® 901 Series II #71033 Overhaul

From Rain City Audio: This Bose® 901 Series II Active Equalizer, #71033, came into the shop for an overhaul recently. It was showing some signs of age, in this case, a bad left channel. Nothing Rain City Audio can’t fix! This … Continue reading

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Bose® 901 Series IV Active Equalizer #509052

From Rain City Audio: This Bose® 901 Series IV Active Equalizer, #509052, was just purchased and sent to Rain City Audio for an overhaul. This unit was originally a 220V model but had already been converted to 110V on a … Continue reading

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Bose® 901 Series II Active Equalizer #66380 Repair

From Rain City Audio: This Bose® 901 Series II Active Equalizer #66380 came through for an overhaul just recently. The owner in California reported that he got these from his father, and the equalizer was sending only the right channel … Continue reading

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Bose® 901 Series IV Active Equalizer #265335 Overhaul

From Rain City Audio: This Bose® 901 Series IV Active Equalizer, #265335, just came through the shop for an overhaul. It’s owner bought this equalizer as a part of getting his Bose® system back up and running and sent it … Continue reading

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Bose® 901 Series I Active Equalizer #9724 Overhaul and Upgrade

From Rain City Audio: This rare early-production Bose® 901 Active Equalizer, serial #9724, came through the shop recently for an overhaul. It’s owner reported that both channels would cut out intermittently, the switches were noisy, and the power lamp was … Continue reading

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Bose® 901 Series IV Active Equalizer #223227 Overhaul

From Rain City Audio: This Series IV Active Equalizer, #223227, just came through for an overhaul. The owner reported it wasn’t making any sounds, just providing a DC offset on the output jacks which was giving his power amplifier some … Continue reading

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