Tag Archives: Series 1

Bose 901 Series I Active Equalizer #50911 Repaired

Posted on December 3, 2013 by retrovoltage

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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Bad Capacitors Strike Again

Posted on February 5, 2013 by retrovoltage

I’m working on another Bose 901 Series 1 equalizer. It looks to be the same manufacturing run as the first one I wrote up last July, uses the same components, and those components look like they’ve had the same failure … Continue reading →

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First Ever Bose 901 Series 1 Active Equalizer Repair

Posted on July 25, 2012 by retrovoltage

This post is almost 15 years old! Check out this much more recent round-up of Bose 901 Series I and II Active Equalizer repair tips and tricks, and leave a comment if you have any feedback. The post you are … Continue reading →

Posted in Electronics, Projects, Speakers, Vintage | Tagged , , , , , , , , , , , , , , , , | 37 Comments

Identifying Your Bose 901 Series 1 Equalizer

Posted on July 11, 2012 by retrovoltage

Bose 901 Series I Active Equalizers came in two varieties, which can be used interchangeably, but have fairly different circuit designs. It’s simple to tell them apart for ordering parts for a repair with a quick inspection of the inside. Both … Continue reading →

Posted in Electronics, Projects, Vintage | Tagged , , , , , , , , , , , | 4 Comments