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FS: Restored Harman Kardon A50K Tube Integrated Amplifier

For Sale: Restored Harman Kardon A50K tube integrated amplifier. 25w/ch, three line inputs, one phono (MM) input, one tape monitor loop/input. Has variable stereo/mono control (blend), separate bass and treble per channel, a center-channel line out ("ambiance" control adjusts that), loudness, and high/low filter switches.


All stock under-the-hood (no mods except to set bias with 120v wall voltage- one resistor change- I also will include the stock resistor with the unit)- restored with all new caps (electrolytics and coupling caps). I forgot to take a shot of the internals before I put the bottom cover back on- but this was a pretty neat/tidy build (and I cleaned it up a bit more- so it's really tidy inside now).


It has a set of testing-nearly-new old-stock GE 7355 output tubes, RCA gray-plate 12AX7 tubes in the phono stage, new Sovtek 12AX7s in the line stage, and an RCA 12AU7 as phase inverter.


Knobs were replaced (originals were missing/bad shape) with new machined aluminum set-screw knobs. Original knurled knob shafts were sleeved/bonded with thin-wall tubing, to allow new solid-shaft knobs to be installed. Tube shields were also refinished (black lacquer). All other finish original. Lettering on front panel in very good shape.


Chassis itself in decent condition- some minor pitting and rust spots, but nothing bad. All jacks and lettering on rear panel in good condition.


All controls cleaned, and all functions tested- unit works fine, and sounds EXTREMELY good. Phono stage is pretty quiet (very little noise), good dynamics, good tonal balance.

Selling for $500.00 plus shipping. I do not have Paypal, BTW- I usually work with USPS postal money orders for payment. Sorry, no international shipping.




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BTW: Just so everyone is aware- these HK amps are kind of a specialty of mine. I've owned an A300 (little brother to the above) for over a decade- completely doing a stem-to-stern rebuild on it over the years.

I've also restored a number of the A500s and A50K amps- I currently own two A50Ks (one is the one for sale here), as well as the A300 (which still does daily duty for me in my home system).

I've even built and sold amps with variations of the A300 circuit, and I'm currently building a version of the earlier model HK250 power amp circuit (same design as the A300/A500, just with different input tubes and a few component value changes).

I'm really a big fan of how well these amps do, with their phono stage and their amp output stage. Very elegant design- simple, but extremely effective, and phenomenal sound- way beyond what they should be, for what they are!

Price drop to $450 plus ship.

This is the only time I'm going to reduce the price. If I don't sell it for this, I will simply just keep it and enjoy it myself. I certainly wouldn't mind swapping this in for my A300 every once in a while...

PS: I know you can find one of these for a lower price elsewhere. Ask yourself what you're getting for your money, though. This one has literally every cap replaced underneath (with caps that are pretty much across-the-board better than original spec, to boot), has everything sorted out for working with current-day power line voltages (bias circuit, etc), has known testing-as-new tubes, and a set of better-than-new knobs, along with everything that could be cleaned and restored, having been cleaned and restored... it's not a "shelf queen"- it's ready to be used every day. And it has one of the nicest faceplates you'll ever see on one of these, to boot...