Monoblocks to consider?

It could very well be your room and speaker placement thats sucking the dynamic life out of your Merlins.Its not the Berning amp.
Before you start selling and spending, start with differant speaker placement.

Sometimes patience and alittle work pays off large.

If that does not do it for you.

Tvads suggestion is agood one.

The subs today have come along, long way. Borrow one or two and see for your yourself.

Or take Rushtons advice regarding the Atma-Sphere monos.
They are everything he says they are.

The Atma-Spheres could very well be a better match for your Merlins. Try them out and see.

Good luck and good listening.

Hi Monty: My system is similar to yours. Joule LAP 150 MkII, AA Prima CDP, and Merlin VSM-MXe but I use a very old Muse subwoofer with it. My amps are Joule VZN-160 and I have been very happy with them for the last 8 years. They are probably the last item in my system I would switch out. Bobby himself uses the VZN-100 at the CES and has done so for a few years.

If you want a fantastic bottom end slam consider the Innersound mono amps,excellent amps with unlimited power.

I'd recommend adding another ZH270 then strapping the channels making them into monoblocks. The combo is killer, I did it with my old Soundlabs and it was the best amp combo I have heard to date. This might make more sense than switching to old school tube amp technology. The Atmasphere will run much hotter, have much less bass drive, are way more high maintenance and less efficient than (2) Berning ZH 270's. with channels strapped.

Chris,
You stated with respect to Atma-Sphere,
Atmasphere will run much hotter, have much less bass drive, are way more high maintenance.

I have been running 4 MA2-MK III's for almost 2 years now, and I have lost 3 power tubes during this time. This is the lowest tube loss I have ever had when running Audio Research, Air Tight, and Bat, and this is with 4 monoblocks or 80 power tubes in total. I have not heard the Berning, so I can not comment as to how its bass compares to Atma-Sphere's, but I have never heard better bass. I agree that Atma-spere's do produce heat, but my air condition easily keeps this in Check and does not appear to noticeably run more than it normally would when amps are not powered up. Sonically, I can not imagine amps sounding better, more accurate or musical.
Happy listening