I went from the Beam to an Arc and I’d say the separation is a bit better, not a great deal better but some.
Overall (not looking at Atmos sources) I’d say I was satisfied with the swap and would do it again.
I think the Arc will be a good option for your larger apartment. The Arc is a much wider and larger soundbar than the Beam. It has 11 drivers (as opposed to the Beam’s five drivers), including two upward firing drivers for Dolby Atmos audio, which will result in a larger soundstage in both width and height.
The Arc supports higher resolution audio codecs like Dolby Digital Plus, Dolby TrueHD, Dolby Atmos, and multichannel PCM. The Beam (Gen 1) only supports up to Dolby Digital audio.
The new Beam (Gen 2) also supports the higher resolution audio codecs but still only has five drivers and lacks upward firing drivers.
NOTE: If you want to take full advantage of the Arc’s audio capabilities, you need a TV equipped with HDMI eARC or you need to get an HDFury Arcana eARC adapter.
I just upgraded Beam 5.1 to Arc 5.1 last week. Very similar situation to you, I sit around 10-12 ft from the TV.
I've had a very happy time with the Beam for a couple of years, and having now heard both soundbars in various configurations I can confirm the ARC is absolutely a better fit for a bigger space, or > 8-10 ft viewing distance, whereas the Beam delivers ample power inside the 6-8 ft range. The Beam still sounds great in 5.1 at a distance, but it clearly relies a lot on the additional speakers. This all seems to be in keeping with Sonos marketing.
The Arc is a material upgrade. While the audio signature is very Beam like, it is delivered with considerably more power, confidence and authority that you would definitely appreciate at the distance you sit. There is also a bit more control overall, and additional clarity, particularly in the high end, and it feels better balanced with the other speakers in the group, especially the sub.
If your TV supports eArc the additional codec supports are very useful. I can finally have my PS5 convert DTS disks to LCPM, and that is now the only time I ever have to change a setting in order to get the best available soundtrack on any of my sources. I like Dolby Atmos more than I expected. Not necessarily hearing helicopters in the ceiling or anything, but the positional audio is satisfying and engaging.
The Arc a big piece of kit - obviously it's a lot more conspicuous in a room than the Beam is. It's also rather expensive - I used an upgrade discount. If you have the budget and an eArc TV, and you're happy to stick with Sonos for home theater, I think the Arc would work for you - I'm really enjoying it myself. If you don't have an eArc TV, consider that you're not going to get all of the features the Arc offers until you change your TV or buy one of those eArc audio extractors.
Closing the loop on this, I’ve received my Sonos Arc and set it up. It’s definitely an upgrade from the Beam and I can confirm that it does a better job in the larger living room of my new apartment.
