Tag Archives: Bose 901

Bose® 901 Series VI Active Equalizer #199732 Repaired

Posted on February 20, 2015 by jwk

Cross-posted from the Rain City Audio Repair Blog: A first for my shop, I recently worked on a Bose® 901 Series VI Active Equalizer! These are considerably newer than the Series I-IV that typically come through the shop, although they’re … Continue reading →

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Bose® 901 Series I Active Equalizer #55382 Refurbished [Repair Blog]

Posted on February 17, 2015 by jwk

Cross-posted from the Rain City Audio Repair Blog: Another Bose® 901 Series I Active Equalizer came through the shop recently for a full rebuild. These are all nearly 50 years old and are definitely showing their age, and this one … Continue reading →

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Bose® 901 Series I #38949 Repaired [Repair Blog]

Posted on February 13, 2015 by jwk

Cross-posted from the Rain City Audio Repair Blog: Another Bose® 901 Series I Active Equalizer came through the shop. These equalizers were manufactured between 1968 and 1973 and are really showing their age: most have degraded in one way or … Continue reading →

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Bose® 901 Active Equalizer Series I #17118 Repaired

Posted on February 2, 2015 by jwk

Cross-Posted from the Rain City Audio Repair Blog: This Bose® 901 Active Equalizer came in through the shop for the standard overhaul service. It was showing its age, as most of these equalizers from Series I and II will do … Continue reading →

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Bose 901 Series 1 Active Equalizer #46453 Repair

Posted on December 22, 2014 by jwk

Cross-posted from the Rain City Audio Repair Blog: Another Bose® 901 Series I Active Equalizer came through the ship, Serial #46453. It came in with a variety of issues, just not sounding like it used to, and the owner requested … Continue reading →

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Bose® 901 Series IV Active Equalizer #116907 Overhaul

Posted on December 12, 2014 by jwk

Cross-posted from the Rain City Audio Repair Blog: Another Bose® 901 Series IV Active Equalizer came through the shop recently. It’s owner shipped it in without the wooden cover for security. This is a bad idea on the Series I/II, … Continue reading →

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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 IV #244005 Repair by Rain City Audio

Posted on December 4, 2014 by jwk

Cross-posted from the Rain City Audio Repair Blog: Bose® 901 Series IV equalizers are coming through the shop more regularly in the past year. It’s expected as these are definitely getting up there in years. This one was sounding muddy … Continue reading →

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Esteemed Bose® Model 901 Active Equalizer – Serial #230 Repair

Posted on October 17, 2014 by jwk

Cross-posted from Rain City Audio: I had the distinct pleasure of working on one of the earliest  Bose® Model 901 Active Equalizers from Series I’s first production run. Serial #230, in fact! It’s made entirely by hand and shows traces … Continue reading →

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Bose 901 Series IV Equalizer #202245

Posted on August 29, 2014 by jwk

A bit different from the run of Series I and Series II that I usually see, I got to fix up this Bose 901 Series IV Active Equalizer which was sent to me from Austin, TX. The Series IV was sold from 1978-1983 and its construction reflects this.

The PCB on this model is single-ended, so can be completely removed from the chassis.

<img class="alignnone" src="https://lh4.googleusercontent.com/-yTJ3z3swIO4/U_wH-zjcj3I/AAAAAAAAkEA/YBDKfs9GTSs/s640/IMG_1459.JPG&quot; alt="" width="640" height="480 Continue reading →

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