purchased A: AKG K-1000 head "speakers" B: nOrh SE-9 amp C: DiMarzio RCA
interconnects D: Stefan AudioArt AKG replacement cable - setup connceted to
computer with Terratec DMX 6fire sound card - in all, a vast improvement
over my proveious experiences with music! - question is for amp which uses
2x12AX7 Electro Harmonix drive tubes, 2x EL-34 Electro Harmonix power tubes,
and 1x 5AR4 Sovtek rectifier tube - received many different replies as to
whether high cost tube replacement will actually give a noticeable sound
quality improvement - Upscale Audio seems a good choice for obtaining
replacement tubes - the high cost of "Mullard" or other "quality NOS tubes
makes me cringe (don't make much money) but I'll save should these Mullard
type tubes be worth it with my setup - any suggestions/opinions/ would be
greatly appreciated before I purchase a backup set of tubes!!

Many thanks, Donn