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Category Archives: Stereo
Bose 901 Series I Active Equalizer #41550 Repair
This Bose 901 Series I Active Equalizer, serial #41550, came into my shop in need of an overhaul after being stored somewhere sticky for many years. After a rebuild and thorough control cleaning with high powered solvents, this equalizer performs good as new! All new capacitors, resistors, transistors and neon bulb will last for a long time to come.

Posted in Audio, Bose, Stereo, Vintage
Tagged Bose, Bose 901, Bose Active Equalizer, Bose Equalizer, bose equalizer repair, bose repair, capacitor, capacitor replacement, repair, seattle radio repairs, vintage
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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 901 Series I Early Production Equalizer #00570 Repair
I just finished a new project over at Rain City Audio – Bose 901 Series I Early Production Equalizer #00570 Repair
This Bose® Active Equalizer is the earliest I’ve ever seen through the shop, serial #570. It’s very hand made and got a complete overhaul, including some upgrades to maximize performance. With all new parts to replace the worn out and failed originals after 46 years, it’s going to sound great for a long time to come.

Check it out at http://www.raincityaudio.us/blog/bose-901-series-i-early-production-equalizer-00570-repair! Continue reading
Posted in Audio, Bose, Hi-Fi, Stereo, Vintage
Tagged Bose, Bose Active Equalizer, Bose Equalizer, capacitor
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Bose Active Equalizer Model 800 #003833 Repair
I just finished a new project over at Rain City Audio – Bose Active Equalizer Model 800 #003833 Repair
Those Bose Active Equalizer model 800 is from the early run of the Bose 800 PA system, which is very similar to the Bose 901 direct/reflecting speaker system. The equalizer had bad noise and distortion in both channels when I got it, but after a repair works and sounds perfect and will last for a long time to come.
Check it out at http://www.raincityaudio.us/blog/bose-active-equalizer-model-800-003833-repair! Continue reading
Posted in Audio, Bose, Stereo, Vintage
Tagged 800 active equalizer, 800 equalizer, 901 active equalizer, 901 equalizer, Active Equalizer, Bose, Bose 800, Bose Active Equalizer, bose active equalizer repair, Bose Equalizer, bose equalizer repair, bose model 800, bose repair, model 800
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Bose 901 Series I Active Equalizer #54925 Repaired
I just finished a new project over at Rain City Audio – Bose 901 Series I Active Equalizer #54925 Repaired
This Bose Active Equalizer #54925 was completely refurbished, received upgraded output capacitors, and sent on to its new home in California where it will sound fantastic for a long time to come.
Check it out at http://www.raincityaudio.us/blog/bose-901-series-i-active-equalizer-54925-repaired! Continue reading
Posted in Audio, Bose, Electronics, Hi-Fi, Stereo, Vintage
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The Speaker Spotter – Speakers of Craigslist – April 18th, 2014
There’s always something interesting for sale on Craigslist, especially in Seattle. Do click the titles to see the original postings with more photos and additional information if you’re interested – otherwise, enjoy the virtual window shopping! Rain City Audio is not … Continue reading
Posted in Audio, Collections, Photos, Speakers, Stereo, Vintage
Tagged 7000A, A25, altec, altec lansing, Avid, Avid 100, Bose, Bose 601, Dahlquist, Dahlquist M-905, DDS1, Dynaco, Dynaco A25, exponential, Fisher, hi-fi, Horn, Klangbox, M-905, multicell, Nova-6, Radio Shack, RB66, Realistic, Realistic Nova-6, Seeburg, Seeburg Discotheque, series III, speaker spotter, Speakers, stereo, Technics, Technics 7000A, Telefunken, Telefunken RB66, tweeter, vintage, VOTT, woofer
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Bose 901 Series II Active Equalizer #111058 Repair and Upgrade
This Bose 901 Series II equalizer just came through the shop for an overhaul and upgrade. It’s in pretty good shape except for a small piece of delaminating contact paper on the side, but isn’t showing any signs of having … Continue reading
Posted in Audio, Bose, Electronics, Hi-Fi, Projects, Stereo, Vintage
Tagged Active Equalizer, Bose, Bose 901, capacitor, capacitor replacement, Equalizer, repair, series II, vintage
2 Comments
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
The Speaker Spotter – Speakers of Craigslist – April 4th, 2014
There’s always something interesting for sale on Craigslist, especially in Seattle. Do click the titles to see the original postings with more photos and additional information if you’re interested – otherwise, enjoy the virtual window shopping! Rain City Audio is not … Continue reading
Posted in Audio, Collections, Hi-Fi, Photos, Speakers, Stereo
Tagged 2001, 8320, audiophile, C35, dome, Duntech, Duntech Soverign, Empire, Empire Royal Grenadiers, Famous Johnzer, Grenadiers, Greybeard, Greybeard Audio KB22, hi-fi, Horn, James B Lansing, jbl, JBL C35, Johnzer, KB22, kenwood, Kenwood KL-8080X, KL-8080X, marble, MCS, MCS 8320, mid, Modular Component Systems, Petroff, Petroff Labs, Petroff Labs Reference, Polk, Polk Audio, Polk Audio RTIA9, Polk RTIA9, PPX-1, Reference, Royal, RTIA9, Soverign, Speakers, tile, tweeter, vintage, Wharfedale, Wharfedale PPX-1, woofer
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Bose Equalizers on eBay Need Service Too: A Photo Comparison
You’ve had your Bose 901 Series I or Series II speakers in storage for a few years, the Active Equalizer packed away with them and now you’ve pulled them out to set up your vintage system once again. Great – … Continue reading
Posted in Audio, Bose, Electronics, Hi-Fi, Stereo, Vintage
Tagged Active Equalizer, amplifier, Bose, Bose 901, capacitor, capacitor replacement, eBay, Equalizer, hi-fi, non-working, rebuild, repair, restoration, vintage, working
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