18Watt.com

Hey I just have a random tube question.
I've owned amps with EL34's and 6L6's and have had an occassion with each (marshall and mesa) where new tubes that seemed fine went and cr**ped out on me.
Most recently with sovtek 6L6. The store I go to for tubes is owned and operated by one guy and I sometimes think his stuff sits on the shelf for a little too long.
I'm just searching for explanations from these two scenarios with two totally different amps and one store.
What's the shelf life of tubes? I know a lot of guys on here and a lot of radio heads probably use vintage tubes. When does vintage become garbage?

Hey LYS,

It is a well known fact that most "new production tubes" are of poor quality, namely because of the lack of effective quality control. New tubes are cheap, and this is one of those reasons. Good NOS (New Old Stock) tubes are expensive, but come from an era of when tubes were built to high quality standards. My advice is to spend to cash for a good set of NOS tubes and not worry about them for years. Or you can stick with new tubes and replace regularly. When a tube is done, it's done. Normally tubes do not go bad if left on the shelf too long, only through use or abuse will they wear out.

I agree.The older the better when it comes to tubes.But,I have had a lot of good new production tubes as well.It depends on the bias setting of your amp when you pop the new tubes in.If they are biased too hot they won't last very long and if they are biased too cold,they don't sound good.Bias needs to be checked every time you change tubes as one tube to the next can draw different currents.