I want to upgrade from Yamaha RX v592 to the 1070. My speakers are the M&K 750s with Surround-55 Tripole back speakers for a 5.1 system. I wasn’t planning on adding speakers for 7.1 sound. How does the 1070 sound in a good 5.1 system, or is it necessary to have a full 7.1 environment?

It is not at all necessary to have 7.1 - the 1070 will work just as well in a 5.1 system as a 7.1. In fact, many rooms are just not conducive to a 7.1 setup because the surround back channels can't be placed far enough from the main listening position.

I don't own a 1070, but I do power my M&K speakers with a 1050. The combination really rocks so you're in for a nice improvement over your Yamaha. As for a possible way to try out 7.1, you may want to look at this website:

www.mksoundstore.com

On it, M&K offers some nice speaker deals including selling a speaker called the "MP5". They're tiny little cubes that sell for $49 each. You could get two of those and see if they add anything to your set up.

I'll add to this as well. I am using M&Ks MPS-45T (in a Center/Left/Right channel set up) and a pair of CS-29s with my 1070 and I couldn't be happier.

I ended up replacing my Yamaha RX with the 1070. (Well, I took my B&W's off the Yahama, bought Atlantic 2200's, and made a new room upstairs around my 1070). The sound difference is really great. If you make the change you won't be disappointed.

By the way, I'm running the 1070 in 5.1 because I have wiring needs that require an electrician for now. The sound in 5.1 is inspiring enough that I'm not in a big hurry to get the 2 RBK's i want to use as rears. I'll do it, but I'm quite pleased as it is.

Since I bought a couple of better front speakes for two channel use I was able to move my front Mirage Omnisats into service to complete my 7.1 setup. I'm sure the placement is not ideal but I have a pretty typical rectangular room and it seems to provide a fuller sound for surround purposes.

The nice thing about the little Omnisats is that they are cheap (and very good) and can be easily mounted on the ceiling. They also are omni-directional and provide a great sensation of space or ambience. The first track of The Animatrix DVD is astonishing with a full 7.1 set up.

Having said all that you get 90% of the effect with 5.1 and I still prefer two channel listening for music (except for the odd SACD or DVD-A).

For the cost of two Omnisats ($58 each?!) and $20 for wire you might as well use those extra two channels since you paid for them!