I have a Conrad Johnson PV2ar preamp (bought new in 1981), solid state Hafler 100W amp going through Anti-cables to '78 Klipschorns.
Due to the high efficiency of the K-horns, when tubes start to age I can hear it easily....sounds to me like "wind" noise.
When the sound of the wind, sometimes a hum, gets obtrusive I know it's time for a tube change.
Brent Jesse has been my supplier for a number of years now and his advice has always been spot-on regarding the sound of NOS replacement tubes.
In my case there is a noticeable sound difference between tubes.....nothing overly dramatic, just a sweet richness that varies from brand to brand.
If your system isn't overly sensitive, and the audible tube sound differences are negligible, I would say it doesn't matter...... why spend the extra money on rare tubes?
Due to the high efficiency of the K-horns, when tubes start to age I can hear it easily....sounds to me like "wind" noise.
When the sound of the wind, sometimes a hum, gets obtrusive I know it's time for a tube change.
Brent Jesse has been my supplier for a number of years now and his advice has always been spot-on regarding the sound of NOS replacement tubes.
In my case there is a noticeable sound difference between tubes.....nothing overly dramatic, just a sweet richness that varies from brand to brand.
If your system isn't overly sensitive, and the audible tube sound differences are negligible, I would say it doesn't matter...... why spend the extra money on rare tubes?