Cary SLI-80 bias help


I purchased a used SLI-80 with upgraded Shuguang Treasure 6CA7 Z power tubes. I decided to check the bias, which Cary says should be 75-100 mA per Channel. Using my GDT-11 meter I put the dial on the A-- portion and selected 200m. When I get the reading it is saying 4.5, obviously far off from what Cary suggests. Am I doing this wrong or is it really that far off? I don't know what effect that would have, but the amp sounds OK as is. I'm worried about truly putting that number at 75-100 in fear my reading is not right. I used this same meter though (it's brand new) to bias my Jolida amp and it was fine. Is 4.5 really 45 in this case?
vortrex

Showing 3 responses by vortrex

It is warmed up plenty and I am using the 200m setting in the amperage as I mentioned. Any other ideas?
Ok, I put the stock KT-88 tubes in and checked the bias the same way, it is 75ma spot on. So, apparently the previous owner never used these Treasure tubes or never re-biased the unit for them. The question now is, should these Treasures get the same 75-100ma?