Hi. Whether that would be overkill or not is a matter of personal preference.  I don’t think that is excessive for that size of room.  But if you want more even sound you should group all four speakers rather than stereo pair them.

PS.  You might get One SLs for the extra two speakers as you might not want or need Alexa on all four devices.

When you’re lying on your sofa the only audio level changes will be in the music itself, so you shouldn’t need any additional speakers.

Going to four speakers will even out the sound levels. Experiment with mono mode as well as stereo pairs and how you locate the left and right speakers. Some folks like mono while other folks like one or the other of the stereo setups. It really comes down to your ears and the trying different locations can be a bit of fun.

At 25 Meters you might even consider adding a third set in the middle of the long wall.

Cool, I'll do it. I'm picking up a used Sonos One from a friend who doesn't really use it, so just need to get one more. 

I considered mono mode, but i listen to a lot of psychedelic music that pans sounds from left to right. I love that feeling of noise moving across the room. 

You might like the front R-L pairing and the rear Paring flipped to L-R.

You could also do that and add the third center pair in mono and see if you get the imaging you like.

In two different shops I have been told that I can only pair 4 sonos one together in mono. Where’s the truth now? I couldn’t find the answer anywhere.

Would I be able to add a sub to the same group of 4 sonos one?

Thanks guys in advance.

I’m not sure how to interpret that. Four Sonos speakers of the same type can be set up in three ways:

1. Four individual mono “rooms”.
2. One stereo pair “room” and two mono “rooms”
3. two stereo pairs, each in a “room”

Any and all of these can be grouped together to play the same thing, in sync.

Note that the term “room” in the Sonos world defines a zone, or set of speaker(s), and has nothing whatsoever to do with physical location. 

The Sonos SUB can be bonded with a single “room”. So it would play in sync with any of the three options above, as long as it was bonded to one of the rooms. 

Hi Bruce, Thank you for your reply!!!

Please forgive my english as not my first language.

I have a squared living room and need 1 speaker at each corner + 1 sub. 

From your message I understand that I can’t have 1 room with 4 sonos one and 1 sub. 

The reason why I am asking is because at high volumes 1 pair of sonos one playing music would make crackling sound with very low frequencies at high volume.

But if you add a sub it will play really good as you probably know.

Now if I create another room with just 2 sonos one and have it play music together with the room with 2 sonos one + sub I will still hear that crackling sound generated by the room without sub..

any suggestion guys? thanks..

Have you proven this crackling issue? While I’ve never reached anything near full volume on either my PLAY:1s or my Sonos Ones, I’ve absolutely never had an issue with crackling. If that’s a problem for you, I would contact Sonos Support directly to discuss it.

If I were you, I’d start with a stereo pair, and bond the SUB to that. Try it out, and then see if you feel the need for another pair.

If you listen to music at that high a volume, you may want to consider the PLAY:5 rather than the Sonos One, it’s a physically larger speaker that can move more air, due to simple physics. 

you are probably right, I should have considered PLAY:5 since the beginning.

as I have already two PLAY:1 + SUB in a room

can I add two more Sonos one and make one room (mono) with 2 PLAY:1 + 2One +SUB?

Thanks again

No, a “room” in Sonos’ software is a single speaker (mono), a pair of speakers (stereo) or a Home Theater room (3.0 up to 5.1), each can have a SUB bonded to it.

No matter what combination of four Sonos speakers you have, you can only have, at best, the three options I listed above. 

I will repeat, Sonos software’s definition of a “room” is a logical abstraction, and has absolutely nothing to do with physical placement. 

Dear Bruce, 

Thank you very much for your patience clarifying all the wrong informations I had been given at Sonos retailers. You just saved me a lot of money. Bless you!

Emilius,

Up to 32 units can be present in a SONOS system. This could be 32 “Rooms” or 16 “bonded” pairs (each pair is a “room”). SUB counts as a “unit”. A “room” that contains a pair and SUB counts as three “units”.

In your large area two or three pairs will provide more uniform coverage. The problem that you are having now is that near the speakers it will be too loud and probably not be loud enough at the far end of the room.

As has been suggested above, alternating L/R for the pairs is helpful in this case because you will always be between a L/R pair as you move around the room. Obviously, the sense of “left” and “right” will swap, depending where the listener is located, but this is better than being stuck between two left’s or two right’s.

and now the picture in my head is complete! what a good idea this forum is..

I’m a little confused by the “rooms” and “units.” So my room is a condo living area maybe 12 X 20. I have a Beam and two rear Sonos SLs on the back of the couch facing the TV. I have enjoyed them so much I’m thinking about getting one for front L and R. Good idea, bad idea or depends? I wouldn’t want to drop the additional $400 if it isn’t going to improve a pretty good sound experience now. Guess I’m looking for some sorta “wow” out of it. Don’t really want the sub-woofer action because I’m on the 2nd floor and don’t want the bass to be a problem for the neighbors. Have a 5.1 Yamaha system at home with the sub-woofer and can feel the bombs and explosions but not near neighbors.

We usually think of a room as a location in our house that has furniture, windows, and doors. In a SONOS system a “Room” is a collection of players that have been given a name. In your case the BEAM along with its ONE SL’s would be a “Room” on your controller. Perhaps you would name it “Great Room” (or whatever) and this combination counts as (3) towards the (32) limit. A stereo pair of players would also be a “Room” and would count as (2). I introduced the concept of “unit” to account for BOOST. Since BOOST is not a player it does not appear in the list of Rooms on a controller, but it does count towards the (32) limit.

No, you cannot incorporate any additional speakers across the front as part of a surround system; BEAM handles everything in the front. While I don’t recommend this, you could add another pair of speakers in the front, but they will be a separate “Room”, not part of the surround system. You could then Group this “Room” with the “Great Room”, but this additional “Room” will confuse the surround somewhat and you will need to tinker with Lip sync a bit to time align the new speakers with BEAM and this might not work as well as you like with respect to lip sync with the video picture.

SUB would be your best bet for some “wow”. You could reduce, not eliminate, bass transmission through the floor if you insert a pad under SUB.

I have a similar issue in a large (1,300 SF) workshop.  I setup 2 Ones in stereo and added a Sub, but at one end of the shop.  They sound great, but at the other end (around a 45 degree corner) of the shop, it sounds too distant.  Was planning to add another pair of Ones at this other end.  It sounds like to do this I would actually leave the current Room as is and create a new Room (Shop2) that I simply sync with Shop1 and probably invert the left/right relationship.  Is that the right way or can I add the 2 new Ones to the existing Room?

No, you can’t add more than the stereo pair to a single room. You’d want to set up that second ‘room’ and then group the two rooms together. 

Add a new one pair at the other end, and set it up to deliver good stereo sound at the other end, doing Trueplay for that pair with the existing pair silent. 

Then, whenever you need the sound to fill the entire space without being too loud at one end of it, group the two pairs via the app, setting the relative volume levels of each pair for best results. Once that is done, you can change overall levels up/down, with the relative differences in volumes still intact.