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Fisher 55-a

I would like to find a FISHER 55-A tube monoblock amplifier to make a stereo set,does any of you know or have one for sale?

Best regards


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I have on I would like to sell.

I have a 55A with the zmatic knob on the front. It is in very good shape. It still has the inspection tag tied to the power cord with string. I got it mid 90's and after testing the tubes I used it for a couple of hours to confirm proper function. I then started looking for a second one so I could have a stereo pair. I did find one once and offered the guy 1K$ for it and he turned me down. It has been sitting on a shelf in my office ever since. The paint is great, no bends in chassis or cage and in general presents itself very well. I would be happy to post/email pictures once I dust it off and take some. PM me if anyone is interested.
The original screws hold the base plate and cage in place. The “The Fisher” oval is missing from the cage but you can see where it was glued on. The factory inspection tag is still attached to the power cord. The auxiliary power outlet on the back has a chip in it. The meter bezel has a chip out of the right side back and some fogging on the top of the front. All the silk screening is in great shape on the chassis. It looks to me like this is mostly original except the bundle of three yellow capacitors seen in one of the pictures.
If the numbers on the inspection tag represent a date this amp may be from 1957.
This amps tube compliment is supposed to be: 2 – GZ34/5AQ4 Full wave rectifier, 2 – EL34 Power pentode, 2 – 6CL6 mini power pentodes 3 – 12AU7 Medium-Mu twin triode
Current tube compliment: 2 - Sylvania (USA) GZ34/5AR4, 2 – EL34 (I’m not sure what kind of tubes these are, they might me Sovtek), 1 – GE 6CL6, 1 – GE 6197 (6CL6 substitute), 3 – GE 5963 (In 12AU7 Socket, an acceptable substitute for a 12AU7 but probably not as good sonically, 5963 tubes were designed to be used in long life computer applications (since when did computers have tubes in them:))).
I would like to sell this amp. I also have the matching preamp. I think it's an 80C with the wood case. It is very clean too.


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Fisher 55A

Guys. Thanks for posting photos of your 55A. What a beast! I'm listening to a pair of 55As right now, through a 400 cx-2. WHOA! Like nothing you've ever heard. I've had 3 pairs of these puppies, this being my most recent acquisition about a year ago. I finally had my tech in Chinatown dial them in for everyday listening.

Mine are 12 digits apart in the serial numbers. One of em is 168 - 16 from 153 which it looks like yours is. I've also got one of the original fisher oval badges!!!!

We can be sure of a two things. 1, there are probably only 10 of these things out there in this kind of condition with the cages, original paint, silkscreen, and black cardboard "toilet paper" tube cap covers nested in between the power and output transformers - just the pinnacle of engineering and craftsmanship that is NOT rivaled since. - Marantz 2's, and 9's included as far as I can tell.

Good luck in your quest, and enjoy!


I'm posting this to your thread because I'm amazed there is not more information about these amps on the interwebs. I'm going to create a blog dedicated to fisher hifi from late 50's early 60's before I sell everything I've got!!!!!
Fisher 55-A

Sorry to dig up an old thread, but obviously you and I are the only ones that have one..

Hoh!!!That was in 2005, yes fantastic amp i still have it (alone...) Mine is the earlier version with 6550/kt88 output tubes, i'm using it in mono mode with 80c pre (just superb preamp) and a altec voice of theater.The result it's simply superb!!!
Your's is the later el34 output tubes version, a more stable amp. Mine have a ''if..Not..''- Runs too hot, but it's not a defect is normal, everything works as it should...If any one out there have one who would like to sell let me know...
Build your own? Here is the info needed, and the mods needed:

The End of an Era: The Fisher 55-A | Audiokarma Home Audio Stereo Discussion Forums

Interesting read, but I think I would just build something better now. And not a class AB2 PA amp. with a weak tube driver.

At a minimum, it needs the 6CL6 follower/driver replaced with a high gm frame grid tube or a Mosfet. Get rid of the interstage xfmr. too, a phase/stability nightmare. They didn't even use a good interstage xfmr. It runs the output tubes at max. plate dissipation at idle. So probably eats tubes, especially new types. Nothing special about the OT either, they couldn't run hardly any N Fdbk through it. Barely makes the audio frequency specs. Over 1% distortion from the grid current problem.
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