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February 2026 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
Tag Archives: amplifier
Neat Little 60FX5 Stereo Single-Ended Tube Amplifier
While digging around, I came across a really simple circuit in the RCA Receiving Tube Manual describing a 1WPC stereo amplifier using only two tubes, the 60FX5 power pentodes, and a single silicon diode. The 60FX5s have high enough gain … Continue reading
1950s Motorola Modded Standalone Tube Amplifier Measurements
I had an unusual project through the shop recently. It’s a Magnavox tube amp from the late 1950s. The owner brought it in reporting he’d purchased the amplifier, pulled from a damaged console stereo and modified to be a standalone … Continue reading
Posted in Audio, DIY, Electronics, Hi-Fi, Projects, Radios and Tubes, Vintage
Tagged amplifier, Magnavox, Tube Amp
3 Comments
Yamaha B-2X Check-Up and Adjustment
I recently had this Yamaha B-2X through the shop. It’s a massive beast of a power amplifier from the late ’80s, delivering up to 170W per channel with 0.002% THD. Being somewhat more recent, this one just needed a quick … Continue reading
Posted in Audio, Electronics, Hi-Fi, Projects, Stereo
Tagged amplifier, B-2X, yamaha
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Sony TA-5650 VFET Integrated Stereo Amplifier Overhaul
Cross-posted from the Rain City Audio Repair Blog: I recently got to work on a very interesting piece of vintage stereo gear from the golden age of hi-fi in the ’70s, the Sony TA-5650 VFET Integrated Stereo Amplifier. It’s a … Continue reading
Posted in Audio, Electronics, Hi-Fi, Projects, Vintage
Tagged amplifier, bias diode, capacitor replacement, integrated stereo amplifier, overhaul, Sony, Sony TA-5650, stereo amplifier, varactor diode, VFET
1 Comment
Boxed Kit Amps’ Gobo Stereo Amplifier Build and Review
If you’re a subscriber to Nuts and Volts Magazine, check out my article in the December 2014 issue where I build, test and review the Boxed Kit Amps Gobo Stereo Amplifier, a great little desktop reference amp for any skill … Continue reading
Posted in Audio, Commentary, DIY, Electronics, Gadgets, Hi-Fi, Projects, Stereo
Tagged amplifier, boxed kit amps, gobo, nuts and volts
2 Comments
VD-1221 Replacement Substitute Diodes
We’re lucky that these days you don’t need to stock very many diodes in the parts drawers for refurbishing most vintage gear – pretty much everything except for the main power supply rectifiers can usually be replaced with some combination … Continue reading
Posted in Audio, DIY, Electronics, Vintage
Tagged 1n4148, amplifier, bias, diode, diode substitute, series, Sony, substitute, TA-4650, TA-5650, TA-8650, varactor, varactor diode, VD-1212, VD-1220, vd-1221, VD-1222, vd1221, VFET
8 Comments
Harman/Kardon Control Amplifier A-401 Restoration
This little Harman/Kardon Control Amplifier, model A-401, just came through the shop for a full overhaul. It was in a pretty sorry state to begin with – one channel distorted, one barely gasping for air, and a world of scratchy … Continue reading
Posted in Audio, Electronics, Hi-Fi, Projects, Stereo, Vintage
Tagged a-401, amp, amplifier, circuit boards, control amplifier, harman/kardon, hi-fi, photos, pictures, rebuild, restoration, stereo, stereo pictures, vintage stereo
8 Comments
Wanted: Vintage HP 1400-Series Vertical Amplifier Plug-Ins for Oscilloscope
I’m looking for plugins for my HP 143A Wide-Screen Mainframe Oscilloscope which I’m in the process of restoring. I’d love to run it as a 15″ high speed X-Y display, and to do so needs matched vertical amplifier plugins in … Continue reading
Posted in Electronics, Gadgets, Projects, Test Equipment, Vintage
Tagged 1402a, amplifier, HP, HP 1402a, HP Oscilloscope, mainframe, oscilloscope, Oscilloscope Plug-In, Oscilloscope Plugin, Plug-In, Plugin, vertical amplifier, x-y display
4 Comments
1977 Yamaha CR-2020 Vintage Stereo Receiver Repair
The Yamaha CR-2020 drives 120W/channel into an 8 ohm load and supports 3 pairs of speakers (but only plays 1 or 2 pairs a time), dual phono inputs supporting both moving magnet (MM) and moving coil (MC) pick-ups, tape-copy functionality … Continue reading
Posted in Audio, Electronics, Hi-Fi, Music, Stereo, Vintage
Tagged amplifier, audiophile, capacitor, capacitor replacement, classic, CR-2020, hi-fi, receiver, repair, stereo, vintage, vintage receiver, walkthrough, yamaha, Yamaha CR-2020
34 Comments
“Won’t that ruin the vintage sound?”
Audio as a hobby sits in an interesting place in the world. There are hard numbers and objective measurements made with lab equipment on one end, and on the other end you have the subjective and variable linguistic descriptions assigned … Continue reading →