What are used tubes worth ?


My ARC VT100 blew one output tube (the filament opened) so I replaced the entire octet.
So, I have seven 6550 output tubes that work fine, and have probably 800 to 1000 hours on them. They are the original tubes that came with the amp.
Any idea what they might be worth ?
Thanks.
mabonn
I can understand where everyone is coming from in this thread...

That said, it's also the reason I get fantastic tubes at such reasonable pricing. As you can see here, people look down their noses at used tubes.

Apart from some of the upper echelon products introduced in the past 5 or so years, older tubes simply perform better than newer variants. By that I mean, both sonically, and when it comes to longevity. In fact, some old tubes seem to defy logic when it comes to how long they'll last.

Claiming NOS, whether true or not, whether known or not, spikes the price folks are willing to pay. The converse also proves true. Obviously the same holds for newer production tubes, as well.

No sleight to anyone who drinks off the top shelf. As for me, I'll buy the same sonics at a huge discount. Use it to your advantage.
I have invested in a Beck RM-1 tube tester. Although only the ears can be the final test of a tube's musicality, it should help avoid bad tubes, at least.
Thanks Rodman99999. I will contact tctubes to inquire about testing.
Does anybody know anyone in the San Diego area who can test them?
@Mr M- You're welcome. There is probably a musical instrument/amp repair shop, in your area, that could help you with that. ie: You might try these guys: (http://www.keyboardservice.com/Organ_Repairs.asp) or (http://www.topgearguitar.com/tghome/)