Generally new tubes come with warranty and used do not. The new tubes
should be more expensive for that reason, but because some used tubes
could be of a rare maufactured type today, they could demand a
premium, so there is no set rule, instead personal or market value
would be the key there. Used tubes can have a different sound than
brand new tubes but then they are that much closer to the ends of
their useful lives all other things being equal. Trouble with tubes is
that things are never equal...
- Bill

--
www.uptownaudio.com
Roanoke VA
(540) 343-1250
"musicdude" wrote in message
...
While I have owned tube amplifiers, I did not get to experiment with
the
sonic differences between two sets of identical KT88 tubes, one set
new
and one set with 200 - 300 hours on them.

1) Would one expect to hear a difference in the audio performance
between these two conditions?

2) Is there a market price difference between these two
conditions?