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New tubes...far more power??

I replaced my quad set of KT150's in my tube mono blocks a few days ago...replaced with a new set of KT150's that were quad balanced and now for some reason the power output is considerably more. So much so that i need to drop the volume control on my preamp by three notches! Plus, the sound quality is actually no better than before...and maybe even a little strident! Anyone have any idea as to why this would be? 
128x128daveyf
daveyf's avatar
daveyf OP
2,858 posts
 
This amp design doesn't allow for manual biasing. As I said before, I don't know of any auto basing designs that allow for manual biasing..do you??
roberjerman
4,319 posts
 
All tubes, both large and small, produce varying amounts of harmonic distortion: 2nd, 3rd, 4th, 5th ... And this is measurable. Your new set probably has a different harmonic distortion signature. Which you noticed and did not like! There is no "cure" for this! Just accept it - or buy a set from a different manufacturer. And hope that they will have more pleasing sound! 
roberjerman
4,319 posts
 
And if you think that your power tubes will sound better with use - forget it! Tubes, unlike say, wine and whiskey, do not improve with age!
grey9hound
1,112 posts
 
They do have a require a little break in time , just like anything else does.
Probably 50-100 hours
tooblue
1,922 posts
 
I am not aware of anyone manufacturing KT150 tubes other than Tung Sol. As far as tubes not inproving/settling in with some burn in, is not what my ears tell me. Just sayin.
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