On a journey for the last couple of years

Knotscott to be honest no, what would I need to accomplish that? I can google :)

Jfrost thanks for making me laugh... I'm a Mac Fan too but the tariffs are a deterrent, unless of course they have been lifted, I will check into that  

I’m running stereo rythmik E15hp2 and they’ve never let me down. I demoed the rel s/510 before selecting the rythmiks. They are servo controlled and will do pretty much anything you ask them to do, including rearranging the pictures in your walls

Hello @peterrock , lots of good replies!  And certainly not everyone agrees.  But two REL Carbon Specials is a great way to go (I have them so +1 @wswright20 !)

But I think and have found better amps make speakers sound better in many ways even if they can’t make them go lower. And more power is always good...more ease and effortless flow of music...With all that pretty Moon equipment I would go for the best Moon amps you feel like buying.  You can’t go wrong there, and you already have the 740P which is begging to be mated with North series amps!  It will sound better now and be ready for new speakers in the future, should you so decide.  Hello to all others with great advice!

I also don't think its yr. monos but get some Michi M8 Monoblocks, Accuphase or Luxmans (and soooo many more)  if after adding another sub and room treatment(s) you need more.  FYI, REL has very good customer support.