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Line Magnetic 845 Premium bias setting. Advice needed!

Hello everyone,

I recently got a used Line Magnetic 845 premium and I need some help with bias setting.

I am not entirely sure how to adjust the bias with the knobs in the front. 
I believe the correct bias setting is 70mA for the 845 tubes (V1-V2) and 45mA for the 300B tubes (V3-V4).

Here is a photo a small video to see how its setup at the moment:

https://app.photobucket.com/u/mpolyzos75/p/243cc263-f1e0-44b8-8191-30b26d923a30

https://app.photobucket.com/u/mpolyzos75/p/947469e5-f99d-445c-ab8c-d2a8d3aba496

Are the knobs set to the correct setting?

Any ideas are appreciated. 
Many thanks.
mika75
jjss49's avatar
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jjss49
6,612 posts
 
@mika75

wow line magnetic doesn’t supply a manual with proper instructions on how to set tube biasing?! that brand is supposed to be cream of the crop among chi-fi tube amps -- 👎

anyhow, glad you got it figured out...
mika75 OP
6 posts
 
I know,it's crazy!
But the sound the amplifier makes is so good, makes me forget these things
wrm57
1,064 posts
 
Glad to hear it, mika! Thanks for letting us know. There's a good chance I'll pick up one of these myself. What speakers will you be using?


facten
2,888 posts
 
@jjss49

" wow line magnetic doesn’t supply a manual with proper instructions on how to set tube biasing?! that brand is supposed to be cream of the crop "

I don’t know what the story is with the manual that came with the LM amp in question, but the manual that came with my LM 518IA  (845 tubes) was straightforward in words and pictures as to how to bias it.




facten
2,888 posts
 
@mika75
I found you the manual online for the 845 Premium; link is below. The bias instructions are on page 9 and are straightforward.

https://www.line-magnetic.eu/images/line-magnetic/pdf/Manual-LM-845PREMIUM-UK.pdf

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