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Tube match problems

Hi Everybody

I’m new here and would like to ask for your help. 

I got VTL power amp with 6l6 tubes. They were perfectly match. Unfortunatelly when I was recently moving, took out tubes and forgot to mark tubes against sockets. Now I’ve connected back whole my set up, most luckily tubes in wrong sockets, it doesn’t play as it was. I don’t have tools to check bias and it really difficult to find any place dealing with tube amps in my city. Any ideas to solve this issue, which makes me crazy :(((
mn
oddiofyl's avatar
oddiofyl
3,484 posts
 
Best tool ever......

http://www.vhtamp.com/products/vht-accessories/tube-tester-2

Worth every penny.  You can plug a DVM in to verify the analog meters accuracy.   Analog meters can be calibrated, mine were dead on from the factory though.  You don't have to use test points or speaker terminals.  Makes it much safer to bias.  
oddiofyl's avatar
oddiofyl
3,484 posts
 
Use a non ferrous pot adjustment tool for an extra measure of safety
fisher_400
71 posts
 
You could measure the operating temperature of the tubes. Just install tubes with the closest temperatures in pairs. I know this sounds crazy, but I got matches that sounded better this way from a lot of 24 NOS tubes. Hand held thermometers with digital readout are inexpensive & read instantly.
mn OP
13 posts
 
Thanks again to all! 
Indeed very helpful comments!!!
mn OP
13 posts
 
Just another one - If I buy new, matched quad tubes, do I still need to match them with amp?
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