Will I improve the qualitry of sound?

What do you feel your sound is lacking? Not enough bass, harshness, soundstage, not loud enough etc...
One thing to remember is the importance of your room and speaker placement. A $3000 system properly set up can sound as good if not better than a $15000 system which is not. Make sure your system sounds as good as possible in your room, then you'll have a better idea on what to improve upon. Swapping out gear will alter your sound but not necessarily for the better.

There are many great sites offering tons of imformation on placement and room correction, this site is not the one I was looking for but it will shed some light on the subject.

good luck!

http://www.gcaudio.com/resources/howtos/speakerplacement.html

when you mention your speakers (btw that's the only b&w i liked out of the whole line), i also figured that going from 70w to 130w won't make a desired upgrade. aim for 200w amps or add sub.

You can improve the quality of sound, if that's your goal, by going with a better amp with more power. Sure going from 70w/ch to 130 of basically the same sounding amp will make the speakers sound a bit better just by providing more headroom, but you will retain the sonic signature of your 1050 amp for better or worst.

So, my point is, if to improve the sound is your altimate goal, you may want to consider a better amp than 1050 and 1070 put together.
For some affordable amps, look into McCormack older DNA-0.5 Deluxe, DNA-1. Or if you want to spend more, check out Pass Labs, Audio Research, McIntosh, Levinson and the older Krell Class A amps, such as the 100w/ch KSA-100S would be nice.

You can sell your amp and the preamp you are driving it with and get a nice integrated(e.g Krell KAV-400xi). The amplification is very important. Do not neglect it, especially with the N805s. They may be small speakers, but they do like power. And there are plenty of options at all different price points. Best of luck!