LS-50 Speakers (Passive)

I don't think the LS50s have changed.  KEF tries to save money like every other manufacturers: by achieving economies of scale.
What I believe is that the new Q150s are very close to the LS50s.  So the initial LS50 development investment will continue to pay off for years to come.
By the way, the LS 50s are outstanding in the midrange and up - outstanding soundstage and imaging - a great speaker, unique.
I have the ELAC UB5s now, replacing the LS50s.  The Elacs are somewhat a me too product, outstanding for the money, very close to the LS50s, but not as refined imho.  However, the bass (quality, evenness) on the ELAC is absolutely way better than on the LS50s...
So take your pick... a matter of taste.

db, you may be right, but with bass management as you say.  I personally like to let the main speakers play what it was designed to play.  In other words, I crossover to my sub naturally at the point where the mains can't no longer output, and keep the use of the sub to a minimum.

I have both the Elac UB5 and LS50s.  I also have a pair of Totem Hawk as reference.   In my room and with my modest marantz integrated, The UB5s are coming really close to the LS50s in terms of imaging/soundstage, clarity, details.  The LS50s develop more the midrange without being forward, while the UB5s are little less refined and more forward.
The UB5s bass -without the use of equalization or crossovers at mid-bass frequency- are more even and refined.
That's just my take on things!

Unfortunately, the quads have been on the market for 3 years now on no one cared for them in europe.

Just put away the Totems this morning in order to listen to the Elac ub5, and wow am I impressed. Bass output is top notch, imaging and soundstaging are setting a really HIGH bar, not that much less than the LS50s.
Some have mentioned that the LS50s do show what they really are capable of with top notch amplification - no doubt. But that should go for the UB5s as well. The UB5s are a 3-way speaker. For the money, I repeat, the UB5s kill the LS50s in the bass/mid-bass department... and the rest of the frequency range is not too far off.
Obviously, the finish and front baffle of the LS50s outclass the cheap ELAC. But on sonics alone, not really.
I am saving money for the Adante AS-61.  Can't wait.