Please educate me on tubes


Since I know nothing about tubes, I have a few questions:

Vintage, re-issuem NOS, modern production (or if there are other types)? What do these types mean?

Is it safe to buy used? If so, what do you look for?

Should I buy as sets (pairs, quads, matched)?

Where do you get the most, least or doesn’t make a difference? Input, rectifier, output, etc.?

Thanks!
vman71
Great points, Jim, and sorry (though not totally surprised) to hear about your Ebay tube buying woes. I recently was looking at some ECC803S telefunkens also from a guy in Germany, but decided the risks were just too high, esp at those prices!

Anyway, to reiterate, Audiogon (vs Ebay) this is a generally safer forum to buy tubes, IMHO.
Vman71:
There are some trustworthy private tube dealers on Audiogon, but eBay is more risky. Look at the seller's feedback. The crooks get weeded out of Audiogon, and regularly change user ID's to regain anonymity. Also, I've found that good retailers like Upscale Audio, Jim McShane, SND, Vintage Tube Services, etc., have good tubes often at lower prices than Audiogon or eBay. Good luck. If you make a few mistakes, it's just part of the learning process.
Jay
All,

Thanks for the great advice to get me introduced and started with my tube journey! I just received my Eico hf-81 today. It is in very good condition with a partial rebuild. The previous owner took good care of it and did the following to get me started:

- Replaced capacitors and resistors

Mike