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Poll: What's your KT150 bias set to per tube (ma?)

To: Owners with purpose-built KT150 based tube amps and the ability to measure bias for each output tube.

What are you biasing your KT150s to in your amps (45ma, 50ma, 55ma, 60ma, or more) per tube ?

Background:
Today I discovered I had been conservatively running bias a bit too low for my mono tube amps. Was a little thin. Went up +10ma per tube and wow. Hit the tube magic window with increased lower midrange presence and overtones coming in nicely, smooth detail. No loss of soundstage. Still within manufacturer spec for my amps. While I realize it can be circuit dependent for different amp designs, just curious what others have found to be a sweet spot for your KT150s in your amps? Feel free to post the name/brand of your amp and the bias setting if you are able to share. Please disregard if your amps are auto-bias or LED bias only. Thanks in advance for your replies.
decooney

Showing 1 response by ptz

ptz
2 posts
 
I would be interested to know if the amp designer would bless the KT170 tube as the better tube overall for that model and what xxma would be appropriate for that tube.😬

Good to know 60ma is still well below for the KT150. At 50ma my sound tightens up, liquid, speed and power with remarkable naturalness and finesse in the recreation of tonal and harmonic information is the great strength of these mono amps. I have the Brimar CV4003 and Mullard 6201 in my amps. I’m sure my field coil drivers voltage settings play a big part of the sweet sounds too.
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