Sorry if this is a double post I may have gotten booted the first time ai tried, if so please disregard. I have a 12ax7a type tube that has (or no longer has) a brand on it. It sounds great in my 5e3 in V1 (unlike most 12ax7a's) On the tube the text reads 12ax7a and above that it has in this font type {USA}. Any ideas? Thanks.