Re: Is there any device out there that will...
Yeah, it's (get this) called a "tube tester".
They were super commonplace through the '70s or so...my mom tells me that as a kid in the '50s and '60s she remembers going to the 7-11 or the hardware store with her old man while he tested tubes for various household gizmos like the radio & toaster oven...
Anyway, a tube tester ONLY tells how much "life" or burn-time the tube has left in it's glass innards. While that does help a lot with 'matching' (to a degree) it won't ever tell us if that tubes is microphonic, makes noise in cirucit or only under high-gain/stress levels, if it rattles or anything else that determines good vs. bad tonal characteristics in a gee'tar amp.
'Ya still gotta do real-time A/Bing for that.
BTW...if you DO hunt down a tube tester of your very own make sure it comes with the correct[/I ]magic decoder book for your unit! Without it there's no way to deceipher anything that the tube tester says.