IME, amp choice is as important for the KEF LS50s as it is for most speakers. I'm using a 175 watt into 8Ω Ayre VX-5 Twenty. I use two Velodyne HGS-10s low-passed at 100 Hz by a Beveridge RM-3. The sound with a good SACD played on my Ayre C-5xeMP is superb with great sound staging that can be deep and detailed if it's on the disc. I admit the Ayre stuff is pricy even used. I'm using a K-5xeMP preamp, but looking for a used KX-5 Twenty.
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