What power amp or integrated amp are you using with your Harbeth speakers

@jjss49 I agree with you - except had I not brought in my large Earthquake 300 w/channel, 1.6V line in, 120 lbs tank of an amp into my office to do a A/B I would have been content with the Croft. Used my second Metrum Jade DAC as pre.  

It definitely brought the Harbeth to life - adding more dynamics to the music with a punch. All the Croft details were there but with more authority. Vocals were a lot more clear and pronounced. After comparing I thought the Croft vocals were a little recessed. Earthquake made the Harbeth sing without fatigue and sharpness.

Call it a curse - but the reason why my interest in the Aria. Now could be that it's not a big difference between the Aria and Croft - from what you wrote - but that's why I have experts like you who have the experience across different amps and speakers help. 

I'm driving my 40.2's and 30.1's with a combination of the Audio Research Ref 5se tube preamp and the Hegel H590 using the Schitt Yggdrasil R2R ladder DAC as the source.  The sound is sublime in all respects.  As it is when just using the dac, preamp and amp of the H590 integrated.  

But... this morning I was surprised to find that driving the Harbeths with the ARC 5se and my Class D Audio SDS 470C is nearly as good.  It provides 300 watts @ 8ohms and 600 watts @ 4 ohms - plenty of power to control the Harbeths...

A local friend has a Coda Class-A amp driving his Harbeth SHL5s and I was smitten every time I heard them. Enough so that I went a similar route: Harbeth C7ES-3 (better fit for my smaller room) powered with a Pass Labs XA30.5 Class-A amplifier. Sonic and musical bliss.

Driving my Super HL5+ with the SST Son of Ampzilla and use a tube preamp.

My current set-up is a Luxman AX590II, full class A with the 30.2's Sure, a little more power would be nice when I'm cranking the Stones at 100db, but I don't do that much and even then, it's an amazing combination. I had them with a McIntosh amp/preamp but that was not a good match. Mushy is the best I can describe it. So lots of power is not helpful unless it's really good power. Hope this real-world info helps.