Steve-Most people on Ebay can't grade tubes for noise (if they can grade them at all) which is what makes buying expensive tubes there a very risky endeavour. Just because it says Siemens, Amperex, Mullard, Telefunken, Valvo, etc., and it tests like new for mutual conductance (or they claim they are NOS) doesn't mean it will be any less noisy than the cheapest Russian/Chinese tubes. RAM Tube Labs does a great job and so does Upscale with testing and grading their tubes for noise. You pay more, but you can depend on them when you get them.