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Tag Archives: series IV
Bose® 901 Series IV Active Equalizer #501554 Overhaul and Upgrade
From the Rain City Audio Repair Blog: This Bose® 901 Series IV Active Equalizer, serial #501554, came into the shop with the owner reporting that it loses output on one channel and the sound degrades the longer it is powered … Continue reading
Posted in Audio, Bose, Electronics, Projects
Tagged 901, Active Equalizer, Bose, series IV
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Bose® 901 Series IV Active Equalizer #219533 Overhaul
From the Rain City Audio Repair Blog: This Bose® 901 Series IV Active Equalizer, serial #219533, came through the shop for an overhaul. The owner was reporting the left channel went out, so it’s clearly time for an overhaul! A … Continue reading
Posted in Audio, Bose, Electronics, Projects, Vintage
Tagged 901, Active Equalizer, Bose, series IV
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Bose® 901 Series IV Active Equalizer #269557 Repaired
From the Rain City Audio Repair Blog: Another Bose® 901 Series IV Active Equalizer came in through the shop for an overhaul recently. This one was a bit unusual, and represents a fairly significant deviation from the published service manual. … Continue reading
Posted in Audio, Bose, Electronics, Projects
Tagged 901, Active Equalizer, Bose, series IV
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Bose® 901 Series IV Active Equalizer #221114 Repaired
From the Rain City Audio Repair Blog: Another Bose® 901 Series IV Active Equalizer came through the shop, this one serial #221114. It’s owner reported that it had lost one channel, so it was clearly due for an overhaul. It … Continue reading
Posted in Audio, Bose, Electronics, Projects, Vintage
Tagged 901, Active Equalizer, Bose, capacitor, overhaul, rebuild, replacement, series IV
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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 Series IV Active Equalizer #246341 Repaired
Cross-Posted from the Rain City Audio Repair Blog: This Bose® 901 Series IV Active Equalizer came through the shop recently with a variety of intermittent issues impacting its performance. These later series equalizers are still getting to be quite old, … Continue reading
Posted in Audio, Bose, Hi-Fi, Projects, Vintage
Tagged Active Equalizer, Bose, series IV
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Bose® 901 Series IV Active Equalizer #116907 Overhaul
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
Posted in Audio, Bose, Hi-Fi, Projects, Stereo
Tagged Active Equalizer, Bose, Bose 901, capacitor replacement, series IV
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Bose 901 Series IV #244005 Repair by Rain City Audio
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
Posted in Audio, Bose, Hi-Fi, Projects, Stereo
Tagged Bose 901, Bose Active Equalizer, Bose Equalizer, capacitor replacement, repair, series IV
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Bose 901 Series IV Equalizer #202245
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" alt="" width="640" height="480 Continue reading
Posted in Audio, Bose, Stereo, Vintage
Tagged Bose, Bose 901, Bose Active Equalizer, Bose Equalizer, bose equalizer repair, bose repair, series IV, Series IV Active Equalizer
2 Comments
The Speaker Spotter – Speakers of Craigslist – March 14th, 2014
There’s always something interesting for sale on Craigslist, especially in Seattle. Here’s a selection of especially notable vintage speakers and other audio products for sale on the local Craigslist. I’m not affiliated with any of these sales, but if you’re interested, you … Continue reading
Posted in Audio, Collections, Photos, Speakers, Stereo, Vintage
Tagged 12W, 15W, Active Equalizer, Akai, altec, altec lansing, Bose, Bose 901, cornwall, Craigslist, Duchess, E-V, Electro-Voice, Electrovoice, Equalizer, EV, heresy, heresy II, KG4, Klipsch, Regency, S-1117, Sansui, series I, series II, series IV, Series V, SKO, SP-100, SP-12, SP12, speaker, speaker spotter, speakerlab, Speakers, speakers of craigslist, SW 177, T25, T25A, T35, The Duchess, Voice of the Theater, Voice of the Theatre, W-35, WD-35, Wharfedale
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