Tag Archives: Series 1

Bose® 901 Series I Active Equalizer #33133 Overhaul and Upgrade by Rain City Audio

Posted on December 8, 2014 by jwk

Cross-posted from the Rain City Audio Repair Blog: Another Bose® 901 Series I Active Equalizer was through the shop lately, serial #33133. It came in working well enough on its original components for an overhaul and upgrade to ensure it … Continue reading →

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Bose 901 Series I Active Equalizer #30924 Repaired

Posted on March 18, 2014 by jwk

I recently got to work on another Bose 901 Series I Active Equalizer, Serial #30924, which needed some service. It’s coming from the original owner who purchased them new in 1970, they went into storage about 10 years ago when … Continue reading →

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Bose 901 Active Equalizer #20262 Repaired!

Posted on March 4, 2014 by jwk

This Bose 901 Series I Active Equalizer came to me from North Carolina, where it had been stored in original packaging for many years. Unfortunately even with careful storage the equalizer wasn’t in running condition and it looks like the … Continue reading →

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Bose 901 Series I Early Production Equalizer Full Repair

Posted on February 24, 2014 by jwk

I just had another Bose 901 Series I equalizer through the shop for the standard service. It didn’t have a visible serial number, but is definitely a very early production version. The Active Equalizer was revised once through the model’s … Continue reading →

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Bose 901 Series I Equalizer #48830 Repaired

Posted on January 8, 2014 by jwk

I recently had another Bose 901 Series I equalizer in for the standard repair service. It was from the later part of the Second Production run and so had a mixture of capacitor packages depending on the value. It looks … Continue reading →

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Bose 901 Series I Early Production Active Equalizer #1056 Repaired

Posted on December 21, 2013 by jwk

It must be the season because another Early Production active equalizer turned up to be repaired! This is the earliest equalizer I’ve yet seen, too: Serial 1056. It’s in for the standard overhaul to replace long since failed capacitors and … Continue reading →

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Bose 901 Series I Active Equalizer #50911 Repaired

Posted on December 3, 2013 by jwk

I recently had this Bose 901 Series I Active Equalizer, serial number 50911, in the shop for repair. These are a lot of fun to work on and very rewarding for the great sound they produce when they’re working properly. … Continue reading →

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Bose 901 Series I Early Production Active Equalizer #11949 Repaired

Posted on December 1, 2013 by jwk

I recently had a pretty rare piece of equipment in my shop and just finished bringing it back to life – the Series I Early Production Active Equalizer. Bose build the 901 Series I from 1968 through 1972-1973, but they … Continue reading →

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Bose 901 Series I Equalizer #47431 Repaired!

Posted on November 20, 2013 by jwk

Once in a rare while I’ll run across an old Bose Active Equalizer that I buy for myself, but they never last too long – I get a lot of requests to purchase a complete Bose 901 Series I equalizer … Continue reading →

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Bose 901 Series I Equalizer #31345 Repaired

Posted on November 15, 2013 by jwk

I recently had another Bose 901 Series I equalizer on my bench for repair. It was in for the standard service, all resistors and film/electrolytic capacitors included and evaluation of the transistors and other components for replacement as necessary. This … Continue reading →

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