@ortodox
I went from 87 db speakers to 94 db speakers. Much better sound at low volume and less power needed.
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I had a similar experience with going from 85 dB sensitivity (84-86 depending on whose numbers one is to believe) Ohm-Walsh 4 speakers to 92-94 dB Klipsch Heresy IV.
I WAS using an updated (by me) ADCOM GFA-545-II to drive the Ohms (GREAT for RAMMSTEIN!), got into a class AB 6CA7 tube amp - Willsenton R8, totally modified/updated by me - then got the Klipsch speakers and a Tektron TK2 2A3/50I-S amp running 300b tubes.
Just before selling the Ohms, I hooked them up to the class A Tektron and they BARELY sounded like anything but hollow, without presence, a very narrow soundstage, vague, muddy.
I connected the ADCOM amp for the buyer and he was sold on them within seconds of hearing “In Your Eyes.”
I’m using 2A3 tubes now and enjoying 50-60’s Jazz more than ever.
Sensitivity, power driving the right speakers, makes a YUGE difference.
addendum:
Funny, I can remember a conversation I had with the father of a girl I was dating back around 1974 who said “you only need about 2 watts to listen to music” when the stereo we were playing was something like 50 WPC and after 50 years, I’ve come full-circle to pretty much the same conclusion.
YMMV.