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Tag Archives: 901
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 I Active Equalizer #51616 Repaired
From the Rain City Audio Repair Blog: Another Bose® 901 Series I Active Equalizer came through the shop for an overhaul! This one was from the very end of the Series I production run, serial #51616. This one appeared to … Continue reading
Posted in Audio, Bose, Electronics, Projects, Vintage
Tagged 901, Active Equalizer, Bose
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Bose® 901 Series II #101043 Repaired
Cross-posted from the Rain City Audio repair blog: Another Bose® 901 Series II Active Equalizer came into the shop recently for a full overhaul. These equalizers are getting pretty old and even if they power up and pass some sound, … Continue reading
Posted in Audio, Bose, Electronics, Projects, Vintage
Tagged 901, Active Equalizer, Bose, series II
3 Comments
Bose® 901 Series II #102678 Restoration
Cross-posted from the Rain City Audio Repair Blog: Another Bose® Active Equalizer came through the shop, this one’s a Series II. The owner reported that one channel had failed and the switches were badly gummed up. Time for a rebuild! … Continue reading
Posted in Audio, Bose, Electronics, Hi-Fi, Projects, Vintage
Tagged 901, Active Equalizer, Bose, Speakers, stereo repair
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Bose® 901 Series VI Active Equalizer #179043 Repair
Cross-posted from the Rain City Audio Repair Blog: Series VI Active Equalizers are the newest of the set and is on it’s second revision of production even today. Even still, the earliest ones are from the 1990s, and that’s getting … Continue reading
Bose® 901 Series II Active Equalizer #117185 Overhaul
From the Rain City Audio Repair Blog: Another Bose® 901 Series II Active Equalizer came through for an overhaul and some upgrades. These equalizers are necessary to provide the curve shaping needed to get the great sound the 901 Direct/Reflecting … Continue reading
Posted in Audio, Bose, Electronics, Vintage
Tagged 901, Active Equalizer, Bose, Equalizer, series II
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What do we have here?
I was reading about how to build a capacitor checker from the December 1959 issue of Popular Electronics and stumbled across something that looked very familiar. I know that shape. Nearly identical to a Bose® 901 Series I/II cabinet, and even … Continue reading →