@DuranDoranMartell Have you performed the system update in the Sonos app too?

The height audio level control is located under the Arc’s audio settings in the Sonos app:
https://support.sonos.com/s/article/5041?language=en_US

Thanks I found it! Amazing. 

For example - Dolby aAtmos movies from Netflix , into arc and my Sonos 2 app status  tv  (in black and white) movie watching “ Dolby Atmos “ sound . 

Most Dolby Atmos movies are not going to have a lot of height channel activity all of the time. You need to find an Atmos film or show that has a specific scene with clearly defined height channel activity to test out the height channel levels to be able to tell the difference. I recommend Roma on Netflix. It has a pretty active Atmos track and utilizes the height channels pretty well.

You could also download this Dolby Atmos 5.1.2 test tones video. Put it on a USB flash drive and play it through your TV by plugging it into the TV’s USB port.
https://www.reddit.com/r/sonos/comments/hc21uu/dolby_atmos_512_test_video_file_download_link/

Good point - will test it and revert back 

Remember that vertical sound is like the rear speakers on a surround array. Sound designers on films use these channels sparingly and subtly. They don't want it to be obvious or distracting. Atmos is too rare still and a sound designer would never put a key sound effect in a channel that few people would hear. Atmos effects are the gargoyles on the cathedral.

Triple-A video games might ultimately be a better showpeice for Atmos technology because designers can attach a sound effect to an object within the 3D environment and then link the audio to the object's position, relative to your avatar. Allowing for instance a screeching vulture to circle above you on an audio track and fly into the distance when you shoot at it.

In terms of getting the most out of your Sonos Arc- the effect is somewhat dependent on your room. 

One of the reasons I couldn't hear the Atmos effect very well is because I have a small living room in a multi-unit building and I have never been able to turn my Arc much above 20% volume. The up-firing speakers don't really come into their own until you get to 35-40%. In my space those soundwaves get overwhelmed by and lost within the other channels' soundwaves pinging around the room.

The new height volume control does seem to enhance the effect for me. Now I can keep my overall volume low whilst delivering more from the up-firing speakers so that they remain discreet sounds.

I also found that turning the loudness feature off improved the effect. The bass can drown out subtlety. (Noting that I also have a Sonos Sub- which again- is probably too much sound for my little urban flat).

Thanks for that advice and  you have pointed out the true and logical the working  factors of Dolby atoms. FYI - My room size is an average size dimensions (L4.5 x W3.5 X H 2.25) a dedicated TV room with a L shape cloth sofa + one side side manufactured wood shelf cabinet. No other clutters , So should enjoy all the should as transmitted. Sonos arc is on  true play ,  TV is a Dolby atoms vision and Dolby atoms sound TV, Sonos arc + 1x latest sub 3, 2x Sonos one rear speakers . 

FYI - when comparing with My neighbor with has a the same room and size TV room with similar furniture , however using a Nad T787 av system with 7 speakers , I.e 1x centre speaker, 1x sub , 2x front , 2x front dedicated  upward firing speakers placed on top of the 2 front speakers ( both these upward firing speakers are in the same angled as the Sonos upward speakers as on the arc . 2x rear speaks (not upward firing ) hence the system is the same format as my Sonos theatre set up , however the neighbors upward firing speakers the sound out of it is very evident all the time and it’s volume is change to min and max can be heard all the time even when we both compared playing the same Dolby atoms movies . So this is puzzling indicates the arc up-firing does not work to gives the same  technically .  ( I am comparing like to like technically) 

hope this will help the Sonos technical team to improve 

Regards 

I am not sure any soundbar will ever be quite as good as dedicated speakers from a high-end amplifier. Soundbars are designed for convenience.

The NAD T787 amplifier alone is 3-4 times  the price of the Sonos Arc (which is one of the most expense soundbars on the market).

The principle of what is suppose to do must be the same ( and Sonos kit  is not cheap , and by the tome you get the full kit as stated not fat off to the NAD + kit)

Sonos’s arc - (Theatre sound system set up). 

I am still in the processes in the investigation of the up-firing Heigh Volume adjustment concern as had stated and will revert back.

Sonos Arc theatre system is a great product. See some of my personal comments as below.

For: (These are My Personal View only with my experience in use)

. Sonos Arc with the theatre sound set up (Refer here as T- kit) is the best kit there is to date (2021), compared with many other top-end quality Dobly  Atmos soundbars products out there. (But however, they had all had the additional DTS/DTS-X features )

. Sono’s Arc produced best sound reproduction and best quality and voices sounded accurate and natural, every spoken word very legible-vocal/voice /speeches etc.. and with the extra offerings, functions to enhance the voice sound to a bonus if we needed.

. A piece of artwork i.e. beautifully designed with excellent materials and looks elastically good too which beautifully fits into any room very well and also enhance the esthetics of the room at the same time. 

. Best easy user experience friendly Sonos S2 App, offerings great functionality and features and enhanced functionalities on version updates. Excellent room sound correction functions, Seamless and user-friendly menus and functionalities. No other offers as much and more. Well done Sonos 

*Well done to Sonos so far, Competition is healthy however don't relax and let others overtake you. Keep it up*

With my experienced in hearing the Sonos Arc T-kit and another No.1 rated Dobly Atmos soundbar (my previous kit). The Sonos Arc theatre kit cost: £1856 GBP (Date 2021)(1xARC + 2 x Sonos one (GEN2) + 1 Sub (GEN3) comparing to the other cost £ 344 GBP more (Date 2021) and when comparing both in my same TV room, I found the latter to be Bulky (HxWxLxD) and the design and materials not esthetics pleasing and the voice sound clarity not as perfect or good as Sono’s arc. (however, it had all had DTS/DTS-X features)

Against (Need improvements) : (These are My Personal View only with my experience in use)

. No rear speaker sound or activity with non-Dolby, Non-HD contents, for the S2 App requires new functionality to allow virtual Pseudo sound. Hence unable to Play Mono good Movies titles and Movies in Stereo ( movies we had till the 80’ +) unable to play on the rear speaker and no function on the Sonos S2 app to allow this, is we like to see an extra button on the Sonos 2 App under the “Sound” heading under “Surround” heading another to see “ Pseudo Sound adjustment for the rear Sonos one speakers) and still able to control the SUB, Rear, ARC TV Volumes. Hope to see this in the near future on the Firmware update. Thanking you in advance Sonos Development Team. ( Notes these this feature are provided on the other renowned Dolby Atmos Soundbars manufacturers) 

.Need to match whether your TV and streaming box will support Atmos on Arc, i.e need eArc HDMI to receive full uncompressed Dolby Atmos sound, or HDMI ARC to allow Pass-through compressed Dobly Atomos/ HD signals, this technical reference info confirmed from the TV manufacturers and from Sonos Tech team. 

. Only one HDMI 

. No DTS?DTS-X support  (I hope to see this feature introduced with a firmware update soon)

. No Bluetooth (would have helped with the flexibility of use, but not a critical issue) 

Appreciate professional feedback and advice - Thank you. 

… 

Note: I still want to stay focused on the present Forum subject - regarding the up-firing Heigh Volume adjustment and will revert back and would appreciate professional advice on how and for it to works - Thank you.

…

End 

@bobmatt From Sonos:

“If the source you’re playing isn’t in 5.1 already, your Sonos home theater speakers will perform an audio up-mix of the stereo signal to create a simulated surround sound. This means you’ll still hear most audio out of the front channels, but the rear left and right speakers will play what we determine to be ambient audio. This is most obvious in action scenes and with movies that have intense soundtracks.”

You can also adjust the Surround Level higher in the Sonos app if you want the ambient audio from stereo sources to be played louder from your surround speakers.

Tried and test as mentioned, it's not there at all, the rear two surrounds are totally silent as mentioned 

What specific stereo source are you testing? What device are you watching it from? Are the surround speakers completely silent when watching any stereo source?

I have provided this info, answered all of the above Q’s, please read in my thread history on the same above  

I don’t see any specific titles, streaming apps, or specific devices mentioned in your posts.

As had stated in my post : 

once again here it is as a summery 

TV : LG Dolby Atmos Vision and Dolby Atoms sound 

Source : Netflix Dolby Atmos content movies 

To your Q - YES the surround speakers are completely silent when playing movies that are in stereo ( 80’s) movies and playing 60’s mono movies 

Hope this has answered your Q 
 

No, not really. What specific stereo and mono movies are you watching? And from what specific source? Netflix? DVD? Blu-ray? VHS? Laserdisc?

I wrote to in my last and many many time : source : movies from Netflix . 
 

From memory stereo from Netflix comes across pretty flat but I can't test it at the moment. Free to air TV stereo sources give me a much better upmix than Netflix I feel. 

Please give us a specific movie title from Netflix so we can test it ourselves to compare.

Faulty Tower, Black adder, vicar of Diby, etc… just to name a few 

None of those listed were recorded in Dolby Atmos, or frankly any 5.1 signal, just stereo, at best, and possibly mono. It’s possible that they’re sending that mono/stereo signal encoded in a Dolby Atmos signal, but you’d still be receiving stereo channels, and nothing at all would be in the height or surround speakers. 

None of these titles are available on Netflix for me to test.

Although I did test Monty Python’s Personal Best on Netflix which is in stereo, and I could hear the music in the introduction through my surround speakers. 

That’s precisely the point 

That is why a system the can make it sound like surround is called Virtual surround function by a device and by DTS/ DTS-X 

I know The senhiser atmos unit can do this and also by LG and Samsung’s Dolby Atmos Soundbar where it plays non 5.1 including Mono transmission into virtual surround by thier units . So please understand I not asking fir the impossible 

I cam see you have not taken the effort or to read and understand my thread history (on this post history here. Please take that effort and do some research too before answering 

Please kindly only reply if you have professional and technical understanding and answers to the solution or recommendation for Sonos team.

Thank you 

@bobmatt The Sonos Arc DOES produce a virtual surround effect with a stereo source. Like I mentioned earlier, I just tested Monty Python’s Personal Best on Netflix which is in stereo, and I could CLEARLY hear the music during the introduction through my surround speakers. I’m sure I could find multiple stereo sources on Netflix and experience the same result.

FYI… I watch YouTube videos in stereo all of the time. I always hear audio playing out of my surround speakers when watching YouTube videos.