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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
3,832 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 .  
mn OP
13 posts
 
Hmmm. Ok. 
I hoped I would be able to avoid bias matching. :)

problem is VTL yet didn’t respond me regarding bias parameters of the amp. 
mn OP
13 posts
 
http//www.audiocostruzioni.com/r_s/ampli/amplificatori/vtl-stereo-45/stereo%2045%20vtl%20222.jpg

my amp is similar to this one and I cannot see test points on it. Does it mean, I have to strip the amp?
oddiofyl's avatar
oddiofyl
3,832 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/
mn OP
13 posts
 
Thanks for reply, oddiofyl. 
I have already red this article in VTL’s site - good one. 

Could you check the link that I posted above, photo of the amp similar to mine and could you advise the test point. To be honestly, I’m struggling to recognize it. 
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