SPEAKERS THAT SOUND ALIVE & DYNAMIC AT LOW LISTENING LEVELS

Your ML electrostats are one of the best options for low level listening. I have 2 suggestions for you:

1. Change amps to perhaps a tube amp or a first watt, an amp designed to sound good at less than one watt, which is where you are listening.

2. Get hearing aids that have a hifi music setting. costco sells the PHillips which are a good choice. the hifi music setting gets rid of any programming designed to help you undersand your spouses voice and simply flattens out the frequency spectrum. your current hearing is lacking in highs and probably some gaps in the mids which makes music sound lifeless. the hearing aids will put life back into the music. You’ll want to turn off the hifi music setting for other activities. for example, a restaurant sounds obnoxiously noisy.

Jerry

PS  Don't sell your Qutest right away.  It is a very good dac and you may find your upgrade isn't an upgrade.

I’d take a look at Volti speakers and maybe Audiokinesis.  Best of luck. 

I listen at 55db-60db every morning before someone else wakes. I don't know if it is the speaker or the amp which permits a decent sound at lower volumes, but I don't feel any aspect of the music is missing other than the volume, with either of my speakers- semi-horns and Magneplaner's- they both seem to have transparency and detail at both ends of the frequency spectrum, dynamics, soundstage, just less of it, and of course a less-level response taking into account the Fletcher-Munson curve. I can't compare what my Maggies or Hornings sound like at 55db to anything else though.

Your Martin Logan's don't work well at 55db?

Regarding planar magnetics and ribbon tweeters, physics would imply less massive drivers require less power to emit the same waves, or level of volume across the frequency range, even if they are low impedance. I don't know how else to word this; hopefully people can follow what I am implying: What properties of a speaker that enables it to sound better at lower volumes. I would think this is a different concept than speaker efficiency at "normal" volumes, and they are not positively correlated? Might be something @erik_squires may have experience with?

Have you heard Magnepan's? Maybe demo some LRS+?

Maggies have always paired well with Bryston's, and you already have the subs if you feel you need them. 

1. Change amps to perhaps a tube amp or a first watt, an amp designed to sound good at less than one watt, which is where you are listening.

I think that is excellent advice. Give that a shot first.

I don’t know your ML’s, but I can confirm my Yamamoto 45 sounds simply wonderful at 0.2 watts per channel on my Hornings. (I'm guessing; didn't measure the output)