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Tag Archives: 901
Bose® 901 Series IV Active Equalizer #244305 Repaired
Cross-posted from the Rain City Audio Repair Blog: Even the later series Bose® Active Equalizers are getting older, and the Series IV is coming up more and more. I just had another one through the shop, this one sent to … Continue reading
Posted in Audio, Bose, Electronics, Hi-Fi, Projects, Vintage
Tagged 901, Active Equalizer, Bose, series IV
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Bose® 901 Active Equalizer Series I #37582 Overhaul
Cross-posted from the Rain City Audio Repair Blog: Another Bose® 901 Series I Active Equalizer came through the shop just recently for a full overhaul. These Series I equalizers were made from 1968-1972 and most are beginning to experience component … Continue reading
Posted in Audio, Bose, Hi-Fi, Projects, Vintage
Tagged 901, Active Equalizer, Bose, series II
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Bose 901® Series II Active Equalizer #114150 Overhaul
Cross-posted from the Rain City Audio Repair Blog: This Bose® 901 Active Equalizer came through my shop recently for a full overhaul. After so many years, the electrolytic capacitors in these units leak and go open, and the resistors drift … Continue reading
Posted in Audio, Bose, Hi-Fi, Projects
Tagged 901, Active Equalizer, Bose, series II
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Bose 901 Series II Active Equalizer Repair #126500
This Bose 901 Series II Active Equalizer came into the shop for a complete overhaul after it suddenly stopped working entirely. While in the shop it also got upgrades to the output capacitors and added 4%-silver solder for the lowest joint resistance possible. After a full rebuild and live listening test it’s ready to go back home and serve faithfully for many years to come.

Posted in Audio, Bose, Stereo, Vintage
Tagged 901, 901 Series II, Bose, Bose 901, Bose Active Equalizer, Bose Equalizer, capacitor upgrade, vintage
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Bose Active Equalizer Model 800 Repair – Bose 800 Active Equalizer
A new one for the shop, I recently worked on a Bose Active Equalizer model 800. This is very similar to the Bose 901 Series II active equalizer; the 800 series were Bose’s PA speaker series from the same model … Continue reading
Bose 901 Series 1 Equalizer #29827 Repaired!
I recently got to fix up another Bose 901 Series 1 equalizer which I received for repair. These are some of my favorite electronics to work on – they’re easy to work on and each one has its own history. … Continue reading
Posted in Electronics, Projects, Speakers, Vintage
Tagged 901, Active Equalizer, Bose, Bose 901, capacitor, capacitor replacement, Equalizer, hi-fi, repair, Series 1, vintage
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Bose 901 Series 1 Equalizer #35793 Plays Again! [Repair]
I recently had a chance to repair another Bose 901 Series 1 equalizer. This makes quite a few of these that I’ve written up on here. One of my favorite things about seeing copies of the same model is getting … Continue reading
Posted in Electronics, Projects, Speakers, Vintage
Tagged 901, Active Equalizer, Bose, Bose 901, capacitor, capacitor replacement, Equalizer, repair, resistor, restoration, vintage
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