Rolling KT150s in Primaluna hp integrated

I’m on day three of running these tubes constant.

The KT150’s power is unquestionably present. There’s more of everything while the speakers are controlled by the amplifier. Bass is more robust than any other power tube I’ve used. Highs soar. Midrange is big, BUT the midrange is not as thick and creamy as EL34s/7581s.

If someone were asking me what KT150s sound like in a Primaluna amp, I’d say that it’s definitely something worth and necessary to hear for yourself. The difference in sound (bass, highs, and control) with the KT150 is so stark it’s like listening to a different amplifier than I’m used to. There’s so much to like with this different setup.

I’m curious to see how these break in and how much I’ll miss that darker, syrupy midrange of the EL34 and variants--which I love and am very used to.

Had anyone who owns one of these bothered to check with the manufacture about heater current draw on the heater circuit of the amp?

As 4 x EL34's draw 6amps, but 4 x KT150's can draw 8amps, this is enough increase to cook and damage things over a period of time 6 to 12 months or so, or even shorter depending the headroom the heater circuit has. 

Cheers George   

Yes, georgehifi, Primaluna endorses the use of KT150s in this amp.  

Many folks run these in Primalunas without issue. 

Are you saying that you think it's a problem based on your personal review and expertise?  I'm having trouble understanding your point. 

jbhiller
  Are you saying that you think it's a problem based on your personal review and expertise? I'm having trouble understanding your point.

I've had tube amps come to me for repairs on the heater circuit too many times because customers have put in more powerful tubes and not bothered to see/check if the heater has the same current draw as the tube it was designed for. They think if the tube is interchangable it must be fine. 

And in this case the KT150 can have 30% more heater current draw over the EL34, on the rectifiers and heater winding of the transformer. This sometimes doesn't show up as a fault till it's been used/cooked for a while.
Tell tail signs are the power transformer is quite a bit hotter or you can smell something that wasn't there with the EL34's 

In case you did know the hottest running section of a tube power amp is the heater circuit & filaments

Cheers George        

Thanks George.  Primaluna endorses the use of KT150s.  With your background, you may be interested to see how they run their tubes and how sizable the power transformers are for the application.