LS50 Wireless fail, or is old gear that good?

It has nothing to do with old vs. new. You are comparing two completely different type speakers. The ML is a large ESL with a 8 inch woofer and the KEF is a tiny powered 2 way with a 5 inch woofer. Besides the speakers I don't think the amps in the KEF would come close to the Threshold!

You make a good point about the difference in speakers. I also tried a pair of Thiel 1.6's in place of the ML's with basically same result. I'm a source first guy, so figured the iPhone as a source for the old gear would level the playing field. And yes, the Threshold is a beast!

It's probably a new thread, but I wonder how the old ARC>Threshold>ML's would compare with similar modern counterparts. Surely the new stuff is better, but by how much?

Not much. Maybe none at all!

I’ve been doing a bunch of listening this past week to both passive and active LS50’s.

The passives need a bunch of power in my oppinion.  200 watts @ 8 ohms and 400 watts at 4 ohms starts to wake them up!  I have mine paired to a Rel T9i subwoofer, a little topping t60 amp, dragonfly red dac, tidal on pc  as the source.  The speakers are still new, maybe 15 hours of listening, but they sound really good.  Very transparent and detailed.  My listening room is 11x14x8 and is treated. The system sounds surprisingly good although it doesn’t play super loud and the Ls50’s don’t have a ton of bass with a little 50 watt amp, but the Rel makes up for that :)

Anyhow, the Passive Ls50’s sound great in my application and I’m loving them!

A friend of mine went with the Active Ls50’s and set up properly, they are amazing!  They (Active Ls50’s) don’t seem to care what signal you are feeding them; they always sound pretty dang good.  The imaging, timing and coherance are like nothing I’ve heard.  I can’t figure out why the Active Ls50’s have this magic to them; initially I thought it was the dac but maybe it has more to do with the dsp?

Regardless, the Active LS50’s fill his large space quite well.  I hooked up my Rel T9i to his Active Ls50’s and it was stupid good.

I would agree that the sounstage is more on the pin point side and not the enveloping side (although the Active LS50’s have incredibly holographic imaging). They don’t have the extension and air to them that some speakers have but for the money I paid, I’m pretty happy with the way they sound!

IMHO, I think it is the difference between the active vs passive LS50. I have the passives and the are fast, transparent and musical with good bass when properly placed and mounted on stands. Powered by SimAudio Moon i3.3 in my second system. The class “A” biasing doesn’t hurt either. Using Morrow Audio SP6 and MA4 cables. 

See if you can trade out of the actives. That is why I went with the passive LS50 Anniversary model. You get to pick the amplifier and cables to YOUR liking not someone else’s idea of what sounds proper in your room with your ears and your music!