Rolling KT150s in Primaluna hp integrated


I’m a mere five hours into these.  This is an alive and kicking tube.  It’s like it had a double espresso before the music starts.  I’m hearing big and strong delivery, but that’s so overwhelming that I cannot focus on midrange.  It’s clear I need some time with these. 
128x128jbhiller
1graber2

Same here.  I am planning to get a PL HP w/KT150 but my concern is the temperature.  Summer in Los Angeles can be as high as 107F.  Can you guys share your experience on how hot the amp gets with those tubes?  Many thanks!
Can you guys share your experience on how hot the amp gets with those tubes?  Many thanks!
From the EL34's 6amp to the KT150's 8amps there will be substantial heater temperature dissipation, if the heater voltage stays at 6.3v and doesn't sag under the extra load that the 150's will put on the filament supply.

Cheers George  
There is no issue with the load imposed by the 150s in this amp. The manufacturer endorses after it did significant testing before doing so.

The power transforners on this amp are massive. That’s why it weighs 60 plus lbs.

With respect to room heating, I live in Chicago so we see all sorts of temperatures from 10 below to 95 to 00 every year. Smaller EL 34 Tubes in their substitutes do not cause too much significant heating in the summer months. But it is definitely noticeable. I went the route of buying a class D amplifier last summer and moving the prima Luna to the basement.

Let me just say that after six months, I sold the class D amplifier and brought the prima Luna back up. I don’t know when I’m going to do this summer. The sound is to to die for so I’m just not sure. I might not care s out the heat. Or, I’ll buy a nice used integrated.

I didn’t have the opportunity to audition all different makes of class D amps. But the one that I did evaluate was not able to impress me long-term.


"The sound is to die for", different amp(s), same result, Jbhiller, I agree. The KT-150 tube is the difference. Temperature effect would depend on many factors, room size, amps, local, season, etc not withstanding George's technical considerations. 
 
In my case it very well may be that there was more miles on my original KT150s than I realized and that putting in fresh tubes made the difference and it had nothing to do with the cryogenic process.
The way to test this, is to send your healthy original used tubes away for cryo'ing (make make sure you get the same ones back by marking them). Then having a listen to them again.

Cheers George