surround sound recommendation

I vote for the ARC ULTRA and SUB.

Hard to imagine any Sonos system ‘overpowering’ any room, unless you turned up the volume to 11, as it were. Given the TV’s width, I would concur with ​@buzz ‘s suggestion. If you can stretch to the Era 300s as surrounds, they might be slightly better, but I also love my Era 100s as surrounds. 

Thanks so much for the advice.

I have two SL 1s….. would they be comparable to the era 100 or no ?

I'd look at the Arc Ultra, Sub 4 and two Era-300s as the best setup. Only if you can't come anywhere close to properly position the 300s would I consider the 100s. I had to do that due to a horrid room layout but I sure miss how the 300s sounded even if they were in spots the spouse refused to consider.

I have a Pair of 300s and a Sub 4 in a 10x10 foot room with a flat 8 foot ceiling and they do not overpower anything, don't have to turn them up a lot normally but it is fun to do when I am left unsupervised. :-)

The Ones won't do Atmos so you'll miss out on some surround sound. As a stop-gap until something better can be had they will serve. I'd do that if the 300s are currently out of reach.

We have a Beam gen 1 in a room similar to yours and while it is adequate for talking heads TV it comes up short for movies and stereo separation is a bit below what we would like for music. If we had room we'd have replaced it with our old Arc but it just wouldn't  fit.

There is a One SL, there is no speaker called a ‘1’, unless you’re talking about the PLAY:1. Which had no SL versions, since it never had a microphone.

But yes, if you’re talking about a One SL, it was the speaker that the Era 100 was designed as a replacement for. I’d think you’d get fairly similar surround performance from it. In a blind test, I’m not sure I’d be able to hear a difference. 

And yes, I’m somewhat annoyed at the naming procedures that Sonos follows. I am not, by nature, normally pedantic, but their confusing naming process drives me crazy. And I completely understand those who confuse the names. But for clarity, and precise understanding….well, you know ;)

I'd agree with that for non-Atmos sources but for Atmos sources the 100 seems to provide more, call it width or presence, at the rear of the room. Likely using the dual Tweeters to spread the Atmos sound out a bit more than the Ones.

Sonos doesn't not do a good job of conveying that information on several of their web pages.

https://www.sonos.com/en-us/shop/era-100#tech-specs

Can I experience Dolby Atmos with Era 100?

As a standalone speaker, the acoustic architecture of Era 100 does not support playback of spatial audio content. For those who want to enjoy content in Dolby Atmos, we recommend Era 300. When paired with Arc or Beam (Gen 2) as rear surrounds, two Era 100 speakers will support playback of Dolby Atmos content.

Versus

https://support.sonos.com/en-us/article/listen-to-music-with-spatial-audio-on-sonos-speakers

Sonos speakers that support spatial audio

• Arc
• Arc SL
• Arc Ultra
• Beam (Gen 2)
• Era 300
• Sonos Ace