"Arny Krueger" wrote in message
...
Tubes have always been proprietary parts. OK, you HP 200C has say a
6SN7 in it. Which manufacturer's 6SN7 is the right one to use?

Uh..!? Tubes from different manufacturers are _massively_ better matched
than any two transistors or ICs from the _same batch_!

Tim

--
Deep Fryer: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms