FR alone as a guide to whether a speaker is any good by no means tells the whole story. If the FR is bad it will not be a good speaker. However if the FR is good it does not mean it will be a good speaker.
The quality of the drivers matters. Tang Band drivers are close to junk category. Making a really good motor system is a complex task. Most fall well short of the mark. I select only the finest drivers. There is a lot that goes into these drivers that I have posted about often. Bass extension is not the whole story, though important. The bigger issue is linear power handling in the bass/tenor range above sub range. That is that crucial band where the vast majority of speakers fall way short of the mark. That is the major power band range, not the sub. There are actually few manufacturers who build drivers that can cut it in this range.
Dynaudio were founded on the premise of building drivers with superb motor systems. They do not disappoint.
The fact is that Ascend speakers are toys against a Dynaudio speaker.
As I keep repeating adding a sub to an anemic sounding speaker does not make for good sound or an adequate system. A speaker system must be highly listenable without the addition of a sub. Of all the speakers the sub IS THE MOST DISPENSABLE. Most of what is posted here about the need for subs is just arrant nonsense.
Lastly I have a bias to Dynaudios as the two manufacturers that voice speakers closest to mine are Dynaudio and Spendor. I highly recommend both.