Has anyone upgraded from Merlin TSMs?

Merlin’s are still great speakers and still hard to beat for the price. I own the TSM Black Magic, the last version made before Bobby passed, and still use them at a beach house. In order to do better I went with QLN Prestige monitors for considerably more dollars. The Pulsars are a nice option too. But without upping the anti you probably would be chasing your tale.

As just mentioned, all tubes seem to work best with Merlin’s.  I haven’t heard the Billie but on paper appears to be something that could scale up with the Merlins.  Have you tried rolling the tubes?  Some nice NOS 12au7’s might make a BIG difference. For NOS  I’d look at some Mazda, RCA, Amperex or Mullard.  All will sound different but depending on what tubes you have now can make a big improvement. I’m breaking in some Psvane new release 12au7’s now in my pre and combined with a class D amp sound very, very nice as well, particularity for the $$$ invested.