Phono preamp tube rolling.

Lewm is right, tube rolling will drive you crazy. The most important characteristic for a phono preamp is low noise. Both RAM Labs and Upscale Audio test their tubes. It is better to spend more on the super low noise tubes or Kevin's stash which are also superior in other parameters. Tubes are quite variable in these regards. With tube testing you know what you are getting. It's a good investment as preamp tubes can last a very long time. I change my phono stage tubes every 5 years whether they need it or not and my unit stays lit 24/7 (when I have a turntable:-(

Tom, What is “pyseabo”? Is it another word for “placebo”? Or did autocorrect do damage to your intentions?

to the OP: I try to use high quality tubes. Once or twice I’ve paid extra to RAM or Kevin for matched or low noise tubes. However tubes age at different rates, so what are matched or low noise tubes today might not be so in a month or 6 months. Still it’s hard to argue not to start with low noise for the input and any other gain tubes in a phono stage. Beware that boutique or NOS vintage tubes sold these days are very likely to be fakes. I have some Telefunken and Amperex tubes that I bought in the late 70s; I believe they’re real but I have no gear that requires a 12AX7 or AU7. I don’t “roll” tubes with any expectation that SQ will improve because of the brand or provenance. I replace tubes that I suspect are near the end of their lifespan.I own a good tube tester, but the real way to test a tube is to measure how it is functioning in the equipment. To do that you need a knowledge of electronics and how to read a schematic.

Yes, tubes age at different rates. It is however my experience that tubes that start off low noise continue to have relatively low noise over their life span. I undoubtedly change tubes prematurely. I change my oil prematurely also. Makes me feel better.

surfmuz, What I meant is that there are nefarious persons who change the markings on tubes that otherwise look very much alike, so as to make inexpensive versions look just like rare and more valuable NOS tubes.  So, before shelling out big bucks for a Telefunken or Amperex or etc, it is wise to equip yourself with the expertise necessary to tell them apart regardless of the labeling on the tube.  On the other hand, I would totally trust Upscale Audio, Jim McShane, RAM, and certainly others with whom I am not directly familiar.  I would NOT buy expensive tubes off eBay.  Also, there are current manufacture tubes that do sound excellent and are reliable, made by JJ  and Sovtek, for two examples.  There you have good quality at reasonable cost.  In my experience also, some of the Chinese made tubes sound great but have a shorter than average lifespan, way too short.