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How to tell if tubes are matched?

I am esagerly awaiting my first tube amp (not counting my bass guitar preamp). UPS says it is somewhere between Redmond Washington and Massachusetts (?). It uses matched tubes, and I'm wondering if I get them all jumbled up in the excite3ment to listen, is there any way to figure out which tubes are matched? Since I've never heard it before, I won't know if the sound has gone haywire, or if it's sounding as intended. It uses 4 matched pairs, so trying all the combinations until I found the one that sounds best would certainly induce thoughts of going solid state. Do they usually mark them somehow? Will biasing be affected? Will there be an obvious flaw in the sound (i.e no sound)?
honest1

Showing 2 responses by gardengirl

gardengirl
16 posts
 
If your serious get a tube tester from Ebay. We matched gain on 12AX7's for our Jolida hybrid and found it to be WELL worth while. If you have 6L6's or KT88's in the final - you will find a good used tube checker a valuable tool. We matched tubes for our older Conrad Johnson PremierII - also could hear the difference.
gardengirl
16 posts
 
Well we have an old Heathkit that is capable of putting a load on the tubes and the manual will teach you how to grade tubes for transconductance in about a half hour - but then I suppose if I were doing it for a living I wouldn't want anyone to think it is too easy. As far as calibration, hmmmmm, well if two tubes have a reading within five per cent and have gain that is relatively high (after comparing perhaps 10 to 12 of their same kind AND THEN you listen to the ones you THINK are matched - you might just surprise yourself (and anyone else with ears ;-) After all the real test is how they sound or isn't that scientific enough, HA! Only thing this requires is a dozen valves and an old tube checker - anyone that describes it otherwise probably has some scientifically 'matched' tubes that they will sell you. I am still trying to figure out if the quality of the silk screening on the tube will improve the sound. I have seen some real beauties - good luck in any case. I have to get back to thinking about presence edge smear as it relates to original recording quality and what to make for dinner. I'm just a girl - what do I know ;-) ???
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