Bob Carver C-500 worth restoring and/or upgrading??

Always a good idea to have it checked out, but if you brought it up on a variac you would probably be fine.
The C-500 is basically the same as a Phase Linear 400 Series Two amp.  If it was properly stored it might not need anything done to it.

N

OK..this is interesting...the tech I talked to here in N.J., who has been spot-on with his info and help (no charge!)  had an interesting "take" on the variac thing. I digress...Marty, Bob Carver's business partner, told me during my hour-long conversation with him that bringing up the amp to 120v with a variac over a 2-3 day period was a good idea... but...After investigating this whole situation and learning more (and from my own small personal experience with this amp)...I have to say that I would dismiss a lot of what Marty has to say. Marty likes to talk and be the expert..(I am not the only one with that opinion),Nice guy...but... ..Actually I would like to know what Bob himself has to say on the topic. Truly.
Anyway...when I mentioned the variac treatment to my guy here he said: …"Yes...that could be a useful procedure in some situations, but your particular amp, and the particular capacitors in vintage Carvers in general do not respond well to that and in fact, that my C-500s capacitors may respond negatively to that procedure. I have to say, Tim, my guy here seemed very knowledgeable, confident and just laid back in his assessments. He instilled confidence.
Bottom line...I just fired the amp up, no variac...the capacitors seem fine and oh does this baby have some nice punch and depth over my Marantz SR6015 in stereo mode! My Carver could be benefiting from the Schiit Freya + ...but when I play an SACD thru the Marantz 30N and the Freya.."to me" it sounds fantastic. I would really like to compare it to a "modern" solid state stereo amplifier and see how it compares, especially in the base region.
Thanks for your feedback...but I threw caution to the wind! 😎 It’s all good.

Nice story, your situation is almost to duplicate of mine except the 40 year old amplifier in question for me is an Adcom GFA-1. I have been told that both Bob Carver and Nelson Pass were employed by Adcom in those early days. Updating the hardwired power cord seems like it might be worth doing. I like the Adcom but it has a cooling fan that adds a little noise to a quiet room although not much worse than hiss provided by some tubes.

Nice story, your situation is almost to duplicate of mine except the 40 year old amplifier in question for me is an Adcom GFA-1. I have been told that both Bob Carver and Nelson Pass were employed by Adcom in those early days. Updating the hardwired power cord seems like it might be worth doing. I like the Adcom but it has a cooling fan that adds a little noise to a quiet room although not much worse than hiss provided by some tubes. I also live in Northern New Jersey :-)

Well...I have mine in a cabinet...but had a 12v micro fan for a computer...So I cut a vent hole and a hole for the fan in the back of the cabinet...I put the fan on a rheostat so I can run it on low..and since the Carver has no on off switch I got a radio control plug in and put the Carver, the fan and my Schiit Freya Preamp on the radio controlled switch. The Freya has no on off on the remote??? and the mechanical switch is on the back???? WTF? LOL! 
I found out that my Carver is working well...I did something REALLY dumb...and blew a fuse on the Carver. Can't get it anywhere locally!
That fuse and the Carver shut-down circuitry saved my $5000 speakers. PHEW!....now I have to wait a week for fuses!!! LOL!