[decooney]

At first, I was not so sure about KT150s in my Inspire or my current <other brand> mono amps. Got Top to bottom range, yes - for sure! Texture and smooth tone came later, patience paid off but almost gave up with some input tube changes in between. Much smoother now after some burn time in my current mono amps.

At 100hrs on KT150s I went back to a local dealer to compare where he had quite a bit more burn-in time on my same amps with KT150s. The difference at 20-40 hours vs 200-300hrs was unexpected. A nice surprise. Better than my former GLKT88s that I liked quite a bit with a bit more dynamics the former EL34 sound on my other amps. Sold the KT120s with no desire to go back to KT88s or EL34s. Really liking the KT150s now. I can bias my amps down to 40ma per tube vs. 50-60ma They take on a different presentation and deeper sound stage backing them down a tad. Turn them up to 50-55ma and presence comes more forward and expansive which is fun too when you are in the mood for that. Hard to describe, at 40ma bias in my amps its sort of like a smoother EL34 sound with fuller body and more dynamics I did not get with EL34s or KT88s in prior amps nor dryer sounding KT120s in my current mono amps. >>I've since learned throwing KT150s in an amp that's not designed to run them accordingly with higher plate voltage could be a waste of money too.<<. Talk with the amp designer before you spend up on KT150s fwiw.

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