Totsuka: You’ve received a lot of great input from AK’ers. I’ll add my 2 cents.
I own a 500C and an 800B, but not a 500B. I’ll cut to the bottom line: If you enjoy owning vintage tube audio equipment (vs. being a flipper), and given that the receiver in question is in good cosmetic condition, then YES these Fisher tube receivers are worth paying a professional tech to restore. This is a no-brainer IMO. The assertion that these are “rich men’s toys” is ridiculous. (As someone else pointed out, we’re not talking $100k.)
Here’s my 500C (restored by Craig Ostby / NOS Valves) in my office system.
About 6 years ago, I bought this unrestored 500C (including wood cabinet, in excellent cosmetic condition) on eBay for $545 + $65 shipping = $610. Plus $482 for a “deluxe rebuild” yields $1,092 total invested. I don’t give a rat’s patootie what someone else would pay me for it, because I don’t plan on selling. (FYI, I probably have twice this sunk into my X1000.)
Occasionally I’ve found a “bargain” by buying an amp that was already restored. However, I’ve also been burned more than once when I bought an amp that was advertised as having been electronically “restored”, and then I discovered that the amp didn’t work properly because the work was incomplete and/or substandard. Here’s two examples:
- In one case (Fisher X1000) the seller described himself as a professional hi-fi dealer. The ad listed numerous parts replaced, and tests performed, and stated “Having the <XXXXX> Certified label means the product you buy from us meets or exceeds all factory specs and has passed a long list of tests prior to going to auction.” The amp had major issues, and I paid Craig for a complete restoration.
- In another case (Scott 296) the Seller stated “It has been completely refurbished by <XXXX>. This amp is in excellent working order and needs nothing.” This amp didn’t work properly. I had to file an eBay dispute to get a refund.
The safest approach, and the one that will cost the least in the long run, is to have one of the pros perform a complete electronic restoration.
I own more than 2 dozen vintage tube amps – all restored. Plus, many professionally restored antique radios – mostly TOTL models that cost much more than these hi-fi amps. In the pic of my office above, the Scott 299B and Altec 353A were also restored by Craig. The 1936 Philco 680 was restored by Michael O’Brien. The 1941 Hallicrafters SX-28 was restored by a Hallicrafters expert (“Nick”). I have antique radios and vintage hi-fi in every room of my house. IMO anyone who thinks that $1k is an extravagant amount of money to invest in a nice vintage tube amp is in the wrong hobby.
Of course, if you learn electronic repair, then you could do the work yourself and save some money.
Bottom line, my advice is to send the receiver to Craig Ostby / NOS Valves (or another one of the experienced techs on AK) and contract for a complete restoration (i.e., what Craig calls a “deluxe restoration“). I don’t know off the top of my head if the 500B has adjustable bias. If so I’d ask the tech about the possibility of adding top-chassis bias test points. By having a professional tech perform a complete electronic restoration (vs. fixing just what is broken today), then the failure-prone components will be replaced, and the unit won’t be back in the shop every year. And you’ll be enjoying beautiful music.