Sony SS M-7 is a three-way speaker from their ES series. It has three drivers: 8", 4.5 " and 1", all made by Peerless.

The crossover has symmetrical 24 db/slope at 400 and 4000 hz. The cabinet
is heavily braced and is shaped like something between a pyramid and a
rectangular box. How about the sound?
The first thing I noticed was the bass was extremely potent, much deeper and
more powerful than a typical system with a 8" woofer. After I placed on a 13
inch stand and placed about 1 foot into the room, the sound became quite
smooth yet retained a very good vibrant quality. I liked very much the
neutral, even response with no detectable coloration. The high end is
extremely smooth and non-fatiguing. The neutrality of the speaker is due
in part the use of very inert cabinet and excellent engineering of the steep
sloped crossover, coupled with very good drivers(apparently Peerless CC-line
or the equivalent, with non-reflecting dust cover and copper shortening ring
in the magnetic circuit). This speaker can play loudly without distortion
yet also plays well with string quartet. I believe Sony has upgraded this
model into M-7c. Thus, you can probably get the orginal M 7 quite
cheaply from the many Sony outlet stores. Its little brother M3 is also
excellent. M3 is essentially a Sony version of the Wilson Watt and retains the
same even, neutral and non-irriating treble of M7. I believe Sterophile also
had some very positive comments about M9 as well as M7.

I was very impressed after listing to these speakers for several hours and ended up buying a pair for my home audio system. Buying these bad boys really enhanced my system especially for DVD movies with dolby digital sound tracks. These awesome speakers produce good highs for cristal clear dialogue,good mid range for music, and unbelievable lows for boooooms and explosions. These speakers are definitely worth listening to.

These Sony speakers are not bad. I recently bought a pair of them because I worked for Sony over the summer and could get good discount on any Sony product(paid $350 each for these). After almost 2 months, I am quite happy with them.
They have very nice imaging and clear, chrisp mids and highs, although the tweeters begin to sound a little "tinny" when played loud(I mean LOUD). I feel that they can use a little more bass, but that may be because I listen to a lot of rock and metal. Don't get me wrong, the bass it puts out is very tight and musical. What bothers me is that they seem to have a very sharp decrease in bass output once it reaches a certain frequency.(like it's putting out sound at 100Hz loud and clear and then suddenly there is nothing at 90Hz) These are not the actual numbers, just an example. I have no idea where the apparent cut-off of bass output actually is.

I am considering getting a sub to add some "thump". For any acoustic or classical music, though, these are excellent. Especially for the price I paid.
I would not consider getting these at the MSRP of $700, however. I listen to some NHT's and KEF's that can kick these Sonys' you-know-what for $700.

Bryon