Best way to improve the audio of my Sony W7 TV - soundbase or sub woofer?

[nialli]

I'm interested in the Denon DHT-T100 favourably reviewed on AV Forums, which the reviewer seemed to really like. I've recently bought a new Sony TV (the Bravia KDL-42W705B) and, whilst delighted with the picture, am a little disappointed by the sound.
Based on the review I was ready to pick up the Denon, but I now see that Sony has released a wireless sub woofer (the SWF-BR100) for its 2014 TVs that may meet my needs.
But I can't find any reviews on this. Any idea whether I'd be better off with this sub or should I opt for the Denon still? I'm looking to enhance the TV audio, maybe with some music streaming (via my TiVo's Spotify app), rather than a full home cinema experience (which would not be neighbourly). I don't want it too heavy or boomy on the bass either, but would like more detail on the mids and clearer dialogue.
Any views?

 

[Joe Fernand]

Adding a Sub is not going to help with poor dialogue, midrange etc - it'll def add a bit more boom though

Joe

 

[Swindonman]

i'm pleasantly surprised with the sound quality (speech) with my Q70T that i've stopped using my Q accoustic M4 soundbar as to many problems adjusting the volume separately to TV volume.
Would a subwoofer help with overall performance.