The fire amp is not going to be biased high enough to run kt150's or even kt120's unless you have the model made for kt150.You could probably change some resistor values and bias the 150's with the proper voltage.
Being a member of a local audio club I have heard almost all of Dennis's amps and I liked the el84 version the best if you have the right speakers,the kt88 is good too.
Kenny.
Being a member of a local audio club I have heard almost all of Dennis's amps and I liked the el84 version the best if you have the right speakers,the kt88 is good too.
Kenny.

