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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

Showing 7 responses by oddiofyl

oddiofyl's avatar
oddiofyl
4,119 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
4,119 posts
 
Use a non ferrous pot adjustment tool for an extra measure of safety
oddiofyl's avatar
oddiofyl
4,119 posts
 
You will still need to adjust bias.  What matched quad speaks to is that they are identical in current draw and emmision.  

If if you have individual bias potentiometers for  each tube it’s not necessary but I would still get matched tubes .  
oddiofyl's avatar
oddiofyl
4,119 posts
 
I had a VTL Stereo 50 and it has external bias points.  The voltmeter's positive probe goes in the test point and the negative probe goes in the negative speaker binding post of the channel you are biasing.

https://vtl.com/support/tube-biasing/
oddiofyl's avatar
oddiofyl
4,119 posts
 
Post a clear pic directly from above please
oddiofyl's avatar
oddiofyl
4,119 posts
 
The Stereo 50 I had sounded great,  VTL's response to second hand owners of their legacy products..... not so great.
oddiofyl's avatar
oddiofyl
4,119 posts
 
There should be holes, two for each tube.   One is and insulated test point.  If you look inside the other hole , you will see a potentiometer pot... i think it was blue with a white adj. slot.
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