Tag Archives: Bose

Bose® 901 Series IV Active Equalizer #265335 Overhaul

From Rain City Audio: This Bose® 901 Series IV Active Equalizer, #265335, just came through the shop for an overhaul. It’s owner bought this equalizer as a part of getting his Bose® system back up and running and sent it … Continue reading

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Bose® 901 Series I Active Equalizer #9724 Overhaul and Upgrade

From Rain City Audio: This rare early-production Bose® 901 Active Equalizer, serial #9724, came through the shop recently for an overhaul. It’s owner reported that both channels would cut out intermittently, the switches were noisy, and the power lamp was … Continue reading

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Bose® 901 Series IV Active Equalizer #223227 Overhaul

From Rain City Audio: This Series IV Active Equalizer, #223227, just came through for an overhaul. The owner reported it wasn’t making any sounds, just providing a DC offset on the output jacks which was giving his power amplifier some … Continue reading

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Bose® 901 Series I Active Equalizer #7790 Repair

From Rain City Audio: This rare early-production Bose® 901 Series I Active Equalizer, serial #7790, came through the shop recently for an upgrade. It’s original owner bought this new in 1969 and kept it in use until it began to … Continue reading

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Bose® 901 Series I Active Equalizer #28322 Repaired

From Rain City Audio: This Bose® 901 Series I Active Equalizer #28322 came through the shop for an overhaul. The original series, these Series I Active Equalizers have the oldest electronic components which are nearly universally out of their service … Continue reading

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Bose® 901 Series II Active Equalizer #81471 Repair

From Rain City Audio: This Bose® 901 Active Equalizer, Series II #81471, just came through the shop for a repair. It’s owner sent this one all the way from Ontario, Canada for expert repair from Rain City Audio. This one … Continue reading

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Bose® Active Equalizer Test Platform

This project is going to take a while since I’m slammed in the shop, but I’m in the process of converting a Bose® 901 Series I Active Equalizer to  a test platform. With sockets for the transistors, and clip connections … Continue reading

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