Dynaudio or Ohm?

Most of the main issues have been covered here and I don't really know Dynaudio. So, forgive me if this is a bit redundant, but at least it's one more data point for you...

I use Ohm 100s and I'm pretty sure that the spatial presentation will be the make or break issue for most listeners. That's not possible to qualitatively recommend to anyone - you just gotta hear it for yourself and make a call.

The 100 is close to dead neutral IMO and has limited deep bass capability. Further, like a lot of modestly sensitive/efficient loudspeakers, dynamics can be understated at modest listening volumes. The net effect is a "polite" presentation at low SPL. I use a pair of subwoofers with my Ohms which seems to help address all of these issues. As a true full-range system (integrated and crossed in the digital domain via Audyssey), this is IMO a ridiculously good sounding system for the $.

BTW, I also own SF Cremonas, Verity Parsifal/Encores, and Merlin VSMs (as well as Maggie MMGs for use with the same subs as the Ohms). The Ohm/sub system is my loudspeaker of choice for 80% of my listening and 100% of my orchestral listening. FWIW.

Map,

I've used a half dozen different amps with the Ohms over the years, most of them tube designs. Over the last five or so years, I've used solid state amps pretty much exclusively. I still use tubes with the Merlin and sometimes with the Verity.

I use an RTA to measure on-axis FR in my listening room and the 100s get down pretty close to 40hz, (which is actually not at all bad - better than most folks think, I'd imagine) before dropping off quickly. (For context, the Verity P/O cannot get quite that deep, tho it feels more dynamic in the bass than the Ohm). It's quite likely that there's some destructive interference at work in the room, limiting the Ohms' output below 50hz. Obviously, the equalized subs can extend that (pretty much however deep I choose), but they also provide some welcome punch in the kick drum region (50hz). For orchestral music, the subs add weight when the recording provides it (not always).

In my room, depending on speaker position, the bass response also gets quite lumpy below 125ish hz. I can re-position the Ohms to smooth things nicely down to 75ish hz, but I lose some deep bass response. Hence, I use room correction software on my subs to fix that while extending the bottom end (vs stand-alone Ohms) by almost a full octave. This improves integration between the Ohms and the subs, as well as smoothing and extending bass response. The subs also relieve the Ohms of the heavy lifting down low, which seems to provide better dynamic performance when the SPLs are modest.

Like any speaker, the deep bass output from the Ohm 100 is going to be room dependent. In my set-up, the subs make a world of difference, but YMMV.