I am a member of various forums for several of my interests. On one forum there is a bookshelf speaker in the Polk line that gets rave reviews, the LSiM703. The forum doesn't have much information on Ascend, though there are a number of comparisons between the 703s and speakers by B&W, Focal, Totem, Usher and other brands which I would consider more competitive with Ascend.
With that as a backdrop, I got my hands on a set of nearly new Polk 703's and decided to do an A/B shootout vs. my Sierra 2's.
I used 4 songs, picked from the group I auditioned my speakers with when I visited Dave and Dina, played through my Plinius 9100 integrated with no EQ and I level matched each song with an SPL meter. My room is a converted 3rd car garage (18 x 11 x 8) and is sometimes a recording studio, so is treated with broadband panels on the walls and bass traps in all 4 corners, as well as the front and rear walls. Both sets of speakers were placed without grills on my Ultimate Support stands, which are 8 feet from my primary listening position. In summary, the best environment I could come up with for a fair comparison.
Songs: Hotel California - Eagles (When Hell Freezes Over version) ; Freddie Freeloader - Miles Davis (remastered hi-def ALAC file) ; They Can't Take That Away From Me - Diana Krall (hi-def ALAC file) ; In The Air Tonight - Phil Collins (2015 remastered ALAC file).
I won't get into detail on each song, but took notes for each set of speakers, with emphasis on bass, treble and mid-range.
Overall, the Polks were boomy in the low end. Mids were neutral but a bit laid back. Treble was neutral and pretty decent, but nothing special. My overall impression would include the words "slow" and "muddy". By comparison, the S2s were solid and punchy in the low end, with the lower conga on the Eagles song coming through at almost subwoofer level in depth and clarity. The mids were neutral and right where they needed to be, in terms of forward / backward. The highs were stunning (as always). Hearing Miles' exhale during "Freddy" and the clear, breathy vocals from Diana Krall were things I had become used to, if not taken for granted. My overall impression includes the words "fast" and "articulate".
I've wanted to do this comparison for some time. The Sierras and Polks may be in the same price range, but nowhere near each other in terms of musicality. The Polks do better in a Home Theater setup, with the benefit of Audyssey to take care of a few sonic issues. Not better than the Sierras, but better than in my music test.
My Sierras are nearly two years old. I've loved them from day 1, and continue to enjoy them with no reservation. This test only served to reinforce what a fine speaker this is, even when compared to what some consider a very good speaker.
Sorry for the lengthy review, but just wanted to get this all down while fresh in my mind (and ears).