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You need to try different types to see what you like best. The earliest ones were all made in the USA by the usual manufacturers like RCA, Sylvania, GE and Tung Sol. The "plain" version without the "A" suffix can only be used in parallel filament circuits, not series.
I know that I would sell more tubes and make more money if I did, but I'm not in the business of pedaling B. This usually isn't a problem as series circuits are only normally found in TV sets.
The "smooth" plate version has as large totally smooth plate surface. The later version has ribbed plates that look much like RCA plates.
Amperex tubes were originally produced in Holland (The Netherlands) and are very high quality tubes. Some of them say "Made in Holland" and in fact are Japanese.