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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
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
Posted in Audio, Bose, Electronics, Stereo, Vintage
Tagged 71033, Active Equalizer, Bose, series II
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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
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
Posted in Audio, Bose, Electronics, Hi-Fi, Vintage
Tagged 66380, 901, Active Equalizer, Bose, series II
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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
Posted in Audio, Bose, Electronics, Hi-Fi, Projects, Vintage
Tagged 265335, 901, Active Equalizer, Bose, series IV
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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
Posted in Audio, Bose, Electronics, Projects, Vintage
Tagged 901, 9724, Active Equalizer, Bose, repair, series IV
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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
Posted in Audio, Bose, Electronics, Projects, Vintage
Tagged 223227, 901, Active Equalizer, Bose, series IV
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Bose® 901 Series I Active Equalizer #28322 Repaired
From Rain City Audio: This Bose® 901 Series I Active Equalizer #28322 came through the shop for an overhaul. The original series, these Series I Active Equalizers have the oldest electronic components which are nearly universally out of their service … Continue reading
Posted in Audio, Bose, Electronics, Stereo, Vintage
Tagged 28322, 901, Active Equalizer, Bose, series I
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Bose® 901 Series II Active Equalizer #81471 Repair
From Rain City Audio: This Bose® 901 Active Equalizer, Series II #81471, just came through the shop for a repair. It’s owner sent this one all the way from Ontario, Canada for expert repair from Rain City Audio. This one … Continue reading
Posted in Audio, Bose, Electronics, Projects, Stereo, Vintage
Tagged 901, Active Equalizer, Bose, Bose 901, Bose Equalizer, series II
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Bose® 901 Series II Active Equalizer #68953 Repair
This Bose® 901 Series II Active Equalizer was originally a European unit, designed for a 240V mains supply. Most if not all 240V equalizers with U.S. style plugs were sold on military bases in Germany and elsewhere, and returned with their … Continue reading
Posted in Audio, Bose, Electronics, Projects
Tagged Active Equalizer, Bose, rain city audio, series II
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