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February 2023 S M T W T F S 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Meta
Category Archives: Stereo
Bose® 901 Series VI #181070 Repair
From Rain City Audio: This Bose® 901 Active Equalizer, Series VI, came into the shop recently. These are some of the most recently produced Active Equalizers, although they’re still potentially a few decades old at this point in time. This … Continue reading
Bose® 901 Series II #65097 Overhaul
This Bose® 901 Series II Active Equalizer, #65097, just came through the shop for an overhaul. It worked briefly, but failed quickly on its original components. Nothing that an overhaul can’t take care of! This particular unit had its three … Continue reading
Bose® 901 Series II #71033 Overhaul
From Rain City Audio: This Bose® 901 Series II Active Equalizer, #71033, came into the shop for an overhaul recently. It was showing some signs of age, in this case, a bad left channel. Nothing Rain City Audio can’t fix! This … Continue reading
Posted in Audio, Bose, Electronics, Stereo, Vintage
Tagged 71033, Active Equalizer, Bose, series II
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Phase Linear 2000 Upgrade and Overhaul
From the Rain City Audio Repair Blog: I recently got to work on another Phase Linear 2000 pre-amp. These well regarded components are a fantastic part of any stereo system with their high output rating, multitude of inputs and outputs, … Continue reading
Dynaco FM-3 High Fidelity Tuner Repair
I recently got to work on a very interesting Dynaco FM tuner, the FM-3, which was in the shop for an overhaul. The owner reported it wasn’t working that well anymore, which isn’t a surprise given it’s age. These are good … Continue reading
Posted in Audio, Electronics, Projects, Radio, Radios and Tubes, Stereo, Vintage
Tagged FM, FM radio, fm-3, heathkit, tuner repair
6 Comments
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
Posted in Audio, Bose, Electronics, Projects, Stereo, Vintage
Tagged 7740, 901, active equalizer repair, Bose, early production, series I
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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
Posted in Audio, Bose, Electronics, Stereo, Vintage
Tagged 28322, 901, Active Equalizer, Bose, series I
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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
Posted in Audio, Bose, Electronics, Projects, Stereo, Vintage
Tagged 901, Active Equalizer, Bose, Bose 901, Bose Equalizer, series II
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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
Posted in Audio, Bose, DIY, Electronics, Stereo, Test Equipment
Tagged Bose, conversion, Equalizer, sockets, test platform, transistor
3 Comments
Reviewing the Gemtune APPJ PA1501A 6AD10 Stereo Tube Amplifier
I recently picked up an interesting little tube amp via a group buy on Massdrop, the Gemtune APPJ PA1501A stereo tube amplifier. Try saying that three times fast! It’s a cute little single-ended stereo tube amp using a pair of 6AD10 … Continue reading →