Speakers and amplifiers are similar to a lamp circuit. As you add more speakers/lamps, they all play at the same level as if they were connected alone. You can add speakers/lamps up to the load limit of the circuit. For AMP, the load limit is one 4-Ohm, two 8-Ohm, or four 16-Ohm speakers per channel. Speaker #5 is the oddball. You could ignore it, connect it as left or right, or switch AMP to mono.

Thanks very much, Buzz.
 

What’s the correlation between the speaker’s “Max Power Output: 200W” and AMP’s spec “125W/Ch at 8 ohms”? I know that power output is a factor when matching amps and speakers, but, am not sure what to make of it in my scenario. Are these speakers when connected as 2 (or 3) per channel adequate for the Sonos Amp and vice versa - is the amp well suited to drive these speakers?

There is no widely agreed upon standard used to assign a power handling figure to a loudspeaker. In my opinion the marketing department has more influence on the number assigned than engineering. A 200W assignment must mean that this is a good sounding speaker, right?

As a general rule one can burn up any speaker using almost any amplifier if you approach the project properly. If you give me the job “damage this speaker”, I’ll pick an amplifier in the 50W range and give it an 80-100W job. The amplifier has low distortion at 50W, but in my my 80W job the amplifier output will be rich in high frequency distortion energy. Normal music has relatively little energy at these high frequencies and tweeters are not required or designed to operate at high power. My upset of the frequency balance will damage the tweeter. It seems counter intuitive, but a larger amplifier is recommended to users who are habitually damaging tweeters. If the higher power amplifier is then operating within its design limits, it will not be as likely to damage anything. If woofers are damaged, the amplifier is too big, the user needs to be re-educated, or the system redesigned to suit the application.

Actually, my absolute last choice of amplifier in my blow up the speaker project would be a SONOS AMP because it cannot be tricked into the high distortion mode that I’m using above. While I could still damage the speaker, I’d need to use tricks, not available to regular folk, and I will not publish here.

In general, 10W output results in satisfying “loud” in most residential rooms. Music is a series of peaks and this 10W average can be accompanied by a few 100W or more peaks. The ability to handle these peaks results in an “effortless” or “dynamic” feel to the system and relatively little stress to the speakers.

Bottom line: AMP will be fine for your project.

Thanks for the added detail, @buzz. Appreciate your help!