Sansui AU-111G (2001) in UK

Yes its a mine field, at the end of the day as long as they are happy, thats what counts.
 
Hi Fever,
Yes I did all that in the tube forum, dcgillespie http://www.audiokarma.org/forums/showpost.php?p=7832413&postcount=19 made me realise the output concept being used makes the bias quite flexible on this design used on the AU-111. I carried out shed loads of tests with the scope operating the bias down to 15mA and upto 40mA. Could not spot anything on the scope at 15mA or and at 40mA.

Ended up setting it at 30-32mA. This is the start link of the topic. http://www.audiokarma.org/forums/showthread.php?t=593913

So in conclusion for 'me' the bias in Unity Coupled stage as used in AU-111, it can be set to as per Manufacturers spec 40mA at just over 75% of the tubes operating capacity to conform to the design.

I have set mine at 30mA @60% of its rating and have not seen on scope or heard a difference in the sonics.

There must be a optimum point, I could not find it.

What's more is by running it slightly less hot, I am prolonging the life of the rare RCA blackgate's I've installed.

I have also tried the same set of tests with the similar bias approach on a new set of JJ's and a set of Svetlana in the AU-111 with similar results.

Mano
 
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