KT150 to KT120..or KT120 to KT150

Wonder how many amps out there that are running KT150's were actually originally designed to run on KT88's, then modded to run KT120's and finally KT150's? 

Interestingly, my old ARC amp running GE 6550's was super sweet sounding, the NOS GE 6550's were a superb sounding tube; but these days, I believe the newer KT150's and 170's are more resolving and offer better power in the bottom end.

@daveyf, I had a Dennis Had Inspire KT150 Hot Rod amp for a year. Was nice, fairly resolving, yet I needed more than 10wpc for my larger 92.5 db amt/ribbon speakers.  And was sure the 150 tube could do more with more transformer and plate voltage behind it.  Sure enough, two years later ended up with the QS Mono 120 with KT150s. Wow, much fuller, bolder midrange, super transparent, hearing deep in to the sound stage, across the front.  Now he and crew are fascinated with KT170s. A good sign. Glad to see other new tubes coming out.  Would be nice to see WE do something less exotic and more mainstream.  Meanwhile I'm going backwards landing on a blend of old/new sound. Nice. 

My ARC VT100 MKiii  sound really good with 6550 compared ARC Ref 75SE KT150

VT100 MKiii more meat and more like the actual sound

REF 75se, more transparent sound and more like flying on the air ,it is beautiful, just different style

I personally prefer the sound of VT100 a little bit more.

I do not know if I install 6550 in Ref 75se,the sound could be better.

I am using the KT 120’s. I would like to try the KT150’s but I would need 12 of them and they are pricey. What if I don’t prefer them? Too bad there really is no way to just try them.

ozzy

The sound is definitely different with kt150 and 6550. Which one you prefer,I do not know. Each one has his personal preference.

I use two power amplifier exchangeable 2-3 days, and I feel good, and taste the difference.