Good move hanging on to those speakers. You’ll have to spend a lot more to do better. I had two pairs of TSM’s, sold one, and had to replace them with $7k monitors for a marked improvement. But still have my Black Magic version, so I’ve tried several different types of electronics. First, they sound best with tubes. Not sure what version you have but the recent versions will sound better than the older versions with Solid State. But again, best to stick with tubes. Depending on room size and how loud you listen, you can get by with 20-25 tube watts. I like them best with my Atma-Sphere S-30 OTL tube amp (30 watts) but the rooms I used them in were small to medium sized. Even in a larger room though 50-60 tube watts should be plenty of power. As already mentioned they sound very nice with EL34 tubes in triode. They did very nice with my Conrad Johnson mono blocks (60 watts of EL34 triode power) in a 16x24 room. Whatever electronics you decide on the Merlin’s will continue to scale up with better electronics. I also found that they sound best with Cardas or Audience cables and again, they will continue to scale up with good cables.