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

All that blabbing and still didn't say..

BIAS differently makes a difference.. :-) Things are not set in stone from valve to valve either. Some brands of valves act different too..

Seems so. Just heard from my amp designer/builder. My KT150 amps sounded a little dry at 40ma per tube. 50ma showing real hope. Op manual shows 40-60 for my model. Asked if I could go up to 55 or 60ma. Designer shared "60ma is still well below the maximum rating of the KT150 tube". Still well within the safe zone it seems. An easy and fun experiment.

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.

OP what kind of amps are you running? It seems the new 150 are all the rage. The 120s not so much. 

 Am I really missing out on something special? What is the heat index? Is it through the roof.  Are the lower bias settings and big valves running cooler.. What's the deal.. What kind of Horsepower we talking about here? 

I was just tinkering with an old MC225. Talk about sound like a tube amp.. Holy cow.. It has been 5 year sense I fired it up.. It has a wonderful old fashion sound you just can't replace, BUT I don't always listen to Tennessee Ernie Ford or Earl Scruggs either..:-)

Regards

@oldhvymec,   "All the rage", hard to say.   Fit for purpose, yes, most definitely.   Took several steps to get to where I wanted it all to land. It took a lot to best my highly modified parallel strapped triode V12R amp, like yours. Part of this had to do with my speakers, and more options to run different speakers later on. Not sure I will, but knowing I can.

Now running slightly modified Quicksilver Mono 120 amps with KT150 output tubes for footprint consolidation and reduction of heat purposes. Tried KT120s in them too, nah. KT150s better all around in these amps. Capable up to 120wpc, yet I bet I rarely go over 2 watts max ever. I use these amps for mostly low volume listening on larger custom designed 2.5-way air motion (electrostatic) transformer speakers. Set in a fairly well ventilated 14’x19’ room. I don’t have to turn it up to hear everything now, it’s just "there". Much less transformer heat, less amp noise, tubes run cooler. Good power and dynamics resulted. Less complex point to point circuit and wiring too. Easier to upgrade or repair these down the road, all key factors for me. A reduction from 12 to 4 output tubes, yes! Another benefit. And, the 12Au7 and 12At7 small tubes are easy to find.

Goal was to run brand new mono amps with a larger / modern / robust output tubes and select dual triode input/driver tubes on the amp’s input stage, and feed it with a nice 6SN7 based tube preamplifier which I already owned and liked a lot. Wanted slightly smaller footprint Monos, vs. super large 87-100lb stereo amps, another +. Still heavy yet I can move them easier and they take up a little less rack space in open racks, more air.

This initial setup was followed by some more rolling of 6SN7 tubes in the preamp and the small signal tubes on the mono amps to gain back a more familiar tone, texture, and presentation. And, of course typical obsessive compulsive round(s) of interconnect swaps (all over again) finally settling back on all OCC continuous copper single-ended RCA interconnects. Final tune and cherry on the sundae was adding the familiar EVO Mundorf Silver-Gold caps same as I ran in my prior Cary amplifiers. At this point, closing in on the "the" sound I wanted showed a glimpse of hope, then a 200-300hr roller coaster ride with caps settling. After all of this, back to biasing output tubes again recently and, wallah!