Current setup:

Receiver: Denon AVR-4306
HDTV: Sony Bravia KDL-V40XBR1
STB DVR: SA 8300
DVD: JVC XV-S65

I have had the receiver two weeks. I did not yet invest in 5.1 or 7.1 speakers, but connected two pairs of stereo speakers that I have had for twenty years (but still sound fine) as follows:

Front Left and Right: Kef C Series C65
Surround Left and Right: Wharfdale Diamonds

I guess that makes it 4.0 or Quadriphonic !

Question is - will I notice a big difference if I upgrade to a real 5.1 or 7.1 system with subwoofer and center speaker. I was looking at Aperion 422/S8.

Most Cable TV appears not to use the surrounds even though the Denon display shows Dolby Digital.

Only movies appear to use the surrounds, and I would question what percent really use them to full effect.