Can excellent tubes transcend modest amps?

AudioFile, let's clarify this a little. Yes, Pirelli P zeros are worthless on an Impala. However, cheap retreads are a nightmare even to that car.

Jolida sends out their amps with notoriously lame tubes. I don't have a problem with Jolida or ASL gear, I just have a problem with $2 tubes put in them at the factory. Tube upgrades even to modest priced tubes ($10 each) will make a noticeable difference.

Well I tend to agree with Audiofeil. That is not to say that the OEM tubes are WAS, just that you can usually, for just a few more dollars, get new production alternatives that will be quite suitible for you. You don't need to spend big bucks on NOS tubes to get a good result when you are using modest components unless you are seeking a very specific result and you can't find a new production tube that will get you there.

No! Agree with Newbee and Bill.

no, but well designed loudspeakers can

The price difference of most tube amplifiers has more to do with power supply, voltage regulation and output transformer quality than what type of tubes they use. Tube rolling is basically a tweak; so I doubt you're going to turn a $200 amp into a $1000 amp with just tubes. Also remember that amps made in China are much cheaper than elsewhere so the quality comparison shouldn't be readily assumed by a labor rate differential.