How to Setup Your Room for Atmos and Immersive Audio

" I feel like money spent on this type of help (room treatments and acoustics) will be more valuable than any piece of gear you will ever buy"

Couldn't agree more. I've felt thought hat HT installers tend to want to create a dryer, less reverberant field than ideal for music, but the principles apply.

60/40 or 70/30 for absorbing/reflective surfaces as a rule of thumb. Good one. 

More reasons to do Atmos, it is mushrooming:

I’m a believer in the potential benefits of more channels for musical listening. I’ve listened to some Apple Music in 7.1 - no height channels. I thought it was interesting to hear older recordings re-mastered in multi-channel. Some of them worked really well, others seemed to gain little from it. As for two channel mixes in Atmos - some of them work better than others. I don’t hear it as a game changing improvement for 2 channel playback but the fact that the same multi-channel recording can gracefully scale back to 2 channel playback seems like a good thing. For now I’m listening to everything in 2 channel format, matrix up-mixed to 3 speaker playback and finding it to be overall preferable. What I’d like to experiment with is mixing the left, center, and right channels of an Atmos mix back down to 2 channel, and then I’d mix them back up to 3 channel using my own matrix. I want to do this because I don’t like how most Atmos recordings treat center imaged sounds. They play the left and right channels along with the center, or sometimes not the center at all. It’s just plain stereo with a phantom center image. I prefer a strong use of the center channel. From what I can tell it’s not easy to get access to the individual digital channel streams from an Atmos recording so that you can manipulate them to your liking.

Unlike stereo Atmos is mixed so it will translate on any platform. I like the remixes they have done in Atmos like the Beatles but the mixes that are new so the artist is able to translate their intentions in the Atmos palate continue to amaze. Check out some of the dedicated channels for Spatial audio in Apple Music, particularly new album drops:

“As a stereo mixer, what keeps me awake at night is how my mixes are going to translate on someone’s headphones, in a club, on the kitchen radio or on a very nice pair of Focal home hi-fi speakers. I have one mix that has to serve all platforms. Atmos for music is actually a dynamic format so when I create an Atmos mix, it will adapt to the device that it is playing on. Play it on your Sonos Soundbar which is 5.1.2, and it will optimise to play on that device. Play it on your Sennheiser 660 headphones and you’ll get the binaural mix and so on.”

@donavabdear

How is your studio setup going? Are you going to isolate it from the HT?

@kota1 I'm going to give up and hang my extra atoms speakers BL, BR, and the tops even though I know the sound is the boss in Atmos and the imaging works fine now but I know it's not just right. I'll have to add speaker cable and hang the top speakers. I really didn't want to make my room ugly for speakers that are only there for background work. 5.1 is really all people are asking for and if I get to excited about mixing for the rears and the tops my mix won't translate like it should back to 5.1 or stereo. My room has no parallel walls only the floor and ceiling. I love my speakers and the fact that they are so precise in the imaging department is still surprising even after months of listening.

@donavabdear

My room has no parallel walls only the floor and ceiling.

OK, do you have any room measurements yet? How will you apply room correction to your 5.1 setup?

The reason I posted those links above is the panels are portable. With the ASC or Auralex solutions you could have any "walls" (like the Attack Wall") you want.

You talked about acoustics, the reps of these companies help you setup as part of their service.

So, can you post some measurements?

@donavabdear 

if I get to excited about mixing for the rears and the tops my mix won't translate like it should back to 5.1 or stereo

I guess you know your client base and until someone asks for an Atmos mix no need to go there. Better to setup your 5.1 setup just right first.

And treatment for your HT need not be ugly. I went with Auralex because I love bamboo. All of those wooden diffusors you see in my pics are made from sustainable bamboo. It sounded better than fiberglass diffusors in my room. There are plenty of vendors to suit your taste, ASC stuff looks great and is very functional. If you get an Attack Wall the same company could treat both spaces:

here is the hot tip for the most advanced information on multi-channel speaker positioning from the world’s leader on this subject. when i was positioning my own 9.3.6 multichannel set-up, i choose the Trinnov approach instead of the Dolby Atmos approach for my ceiling after much research.

looks like the link to the pdf does not work properly. so google "Trinnov Multichannel playbook", scroll down to "Loudspeaker Position Guide -AVS Forum", then select to get the download of the PDF, then open the PDF.

http://file:///C:/Users/mplav/Downloads/Trinnov_Loudspeaker_Position_Guide_2020.pdf

Thanks @mikelavigne , I got it. I like this better than the guide Dolby puts out, more detailed. I was watching an interview of Peter Lyngdorf who felt the ideal number of speakers in a HT was less than 16, I think he felt the max he says you should do was around 12. I am very glad I saw that video because it saved me $$$ on upgrading to one of the 16 channel processors. The best resource I found for listening to MCH music was Tomlinson Holman’s research when he was working with Audyssey. They found that wide channels were more important than rear surrounds or height channels. (see page 23 in the Trinnov Guide linked below) I A/B with and without wide channels and find his research to be spot on. This link might work:

@donavabdear

This is one of the reasons I like Tom Holman’s work. BTW, if you haven’t checked out @mikelavigne virtual system yet I think you’ll find it a great (perfect?) example of room setup:

Tomlinson Holman research on wide’s states:

1) The front half of the room is more important than the back half!
What is perhaps the most repeated mantra I heard during my visit was how the decision to add 2 rear channels when 7 channel sound offered itself as an improvement over 5 channels is according to Audyssey, a serious error. IF these extra channels are available, they should be added to the front, NOT the rear. Why? Human hearing has far better spatial acuity in the front of us than we do behind us. According to Tom Holman, we can resolve auditory spatial information to about 1 degree in angle in front of us from right to left, (Horizontal plane) and about 3 degrees in height (Vertical plane). Both of these sensitivities are far greater than what we have for sounds coming from behind us. Hence Audyssey’s preference of multiple channels in front and sides, and one required for rear channel sound.

2) Width is more important than height!
Width is crucially important in placing instruments and recreating acoustical space. Concert halls with side walls perpendicular to the stage are considered by experts on the subject to be acoustically superior spaces to fan shaped halls. One of the reasons here is the importance of the early reflections from the right and left side walls perpendicular to the stage. In the "fan shaped" concert halls, the splayed side walls did not support the same kind of early reflections and are one of the main reasons these halls are not judged as good by the experts. To quote Mr Holman, "it is known in concert hall acoustics that the first side wall reflection is the single most important reflection direction, it sets the auditory source width... Channels constrained to plus/minus 30 degrees are too narrow for that". For this reason, the DSX standards (7.1, 9.1 and 10.2) support a left wide and right wide channel at plus/minus 60 degrees to reproduce the kind of side wall reflection you would hear if you were seated in a great concert hall."

@kota1

as far as number of speakers, past a certain number it’s more a room size and immersion by degrees issue. and then there is the reality that to get the best processor and the best feature set, that’s Trinnov, and their entry level is 16 channels (which can be expanded to 20 if need be).

i went from my Anthem AV60 with 7.1.4 to the Trinnov with 9.3.6 the quality difference of what i heard profound. same speakers, just a couple more of them. but night and day. the processor quality difference was game changing. and also the ability of the processor to ’re-map’ the locations of your speakers can make all the difference depending on your room challenges. i have a side window and side patio doors which effect where my 2 side speakers can be. no problem with the Trinnov, it will ’steer’ the perceived location with it’s set-up wizard.

pure magic.

so more speakers only help if the processor is up to the task of optimization.

and the Trinnov is really just a very large powerful computer, not any off the shelf chip set. and completely software based. so upgrades are downloaded and easy. little worry about the normal obsolescence as movie sound evolves.

@mikelavigne

That is very helpful, thank you. I have been in the Marantz ecosystem and felt that everything at the $3K to $7K price point was more of a lateral move regarding features than a step up in SQ, regardless of the brand. There was a night and day difference when I stepped up to the paid Audyssey license and a calibrated mic so the DSP is very important. @brianlucey is a mastering engineer who is mastering in Atmos and gave the Trinnov very high marks. He felt it was essential and to your point, it wasn’t about the channel count but their proprietary DSP. Thanks for the heads up. BTW, I had an issue with a picture window on my right wall. I didn’t want to block the light with a heavy acoustic or blackout curtain. I hung an acoustic lens 3D diffusor (auralex) that let’s the light pass through. It may not be very attractive but completely resolved the acoustic problem that was plaguing my MLP from the window without blocking it.

@donavabdear

You have the "magic" ingredient to knock your sox off immersive audio, POWER. Your Genelec speakers are already TRI-AMPED! Why not make THAT system the ONE and make your HT about your chill space?

With your background there isn’t any reason you couldn’t have a killer studio at home. You got the ears from your years in the studios, now get your home studio acoustically the way you want. You know some engineers actually prefer the ASC Attack Wall over a traditional space. You can set them up on a dime.
You got the speakers, you got the IP, now what about the space?

Measurements??

@kota1 The more I think about it and the more I play with my panning joysticks on my ProTools S4 control mixer I'm thinking symmetrical is not the proper layout for surround channels. In my Home Theater everything is symmetrical and fairly large, I set it up with and without the Lyngdorf Room Perfect DSP it doesn't really make a difference except it seems to turn up all my surround sound speakers. My professional system is not symmetrical other than the front L, C, R speakers and it images perfectly with or without the DSP. I think our brains are fooled by symmetrical surround sounds, symmetrical is not natural nothing really happens like that and our brains can't process rear surrounds coming from equal and opposite angles. Therefore I'm keeping everything a little off of symmetrical and leaning on the object orientation of the phantom channels. I've never heard of someone going about it this way before, the speakers are close to symmetric but not exactly and I'm not using any DSP at all so the imaging is only ½ the distance of the difference of the out of symmetry factor. I think that is the key to very nice ambiences and shockingly tight imaging in the surrounds. I'll let you know where this path takes me. I'l be working on it all night I think.

Also if you know of some good Atmos test downloads that would be helpful, Thanks.

Also I saw Shen Sun today at an amazing performing arts theater here in Boise the music was beautiful and the mics they used were cheap u57s mostly (very low end work hors mics) and the orchestra soundsd wonderful because the room was so good, moral of the story if you have a good room many sins are forgiven.

@mikelavigne 

That guide was good, using those tables I decided to move my top middle atmos speakers to top rear speakers so they can double as my surround heights for Auro-3D (aiming the angle at the MLP as suggested, not firing down at the floor) and I'll leave my rear heights only for Atmos. I was using rear heights for auro 3D, not ideal. Thanks!

@donavabdear

If you use Vudu you can search for atmos and they have the dolby test tracks loaded and you can play for free.

When can you post your measurements?? I don’t know protools so no help there. You will find out quickly if your mixes hold up when you test them in your car or someone elses space.

@kota1 Thanks, one cool thing is that I have 4x Dolby Atmos systems in my house I can play it on a few of those. And I have a 7.1 system in my car that is very good I think Mark Levenson makes it. 

I don't add any EQ to my speakers in the professional rig because I want to be like Al Schmitt and get it right without tweeks as he used to position microphones without EQ for the same reason. I know some of the guys who did "fix" many of Frank Sinatras songs especially the "Duets" album even after they were told to not touch a thing, it's to hard to not make it better when you know you can. 

Listening to Apple Spatial audio atmos mixes are like anything else, some good, some not so good. I like "We Take Requests" atmos mix by Oscar Peterson, all of the Beatle atmos mixes, and Kraftwerk in atmos is really good, play it loud and it just pressurizes the entire room.

@Kota1 Say you have a speaker at 135 degrees to your right behind you and say you have a signal from 225 degrees on your left behind you. You can’t perceive a phantom center channel between them but that is how Atmos works, Atmos creates phantom channels that are moveable. To me the only way to fix this is to not have the surround channels symmetric. A much clearer example is where you have Atmos speakers in the ceiling behind you at equal angles they nearly reach your ears at the same time not allowing your brain to position them well at all. Other than using a very dead room it doesn’t seem like there is an answer other than making the speakers non symmetrical, playback would still work because no two systems would be the same about of non symmetricalness, if that’s even a word. What do you think?

@kota1 So I discovered something that I thought I knew but didn't know for sure. In  acoustics and photography and many other arts there is something called the rule of thirds, well I panned (actually I entered the info) to have the front speakers ⅓ of the way back and ⅓ of the way in, when I did that it felt like I moved into the stage a bit. It was interesting that when these numbers were exact and my head was right in the sweet spot the effect was very strong. I'm not sure panning in the traditional sense would have achieved the same effect. The only other satisfying speaker position was full blown stereo 100% left and right which felt more natural.

It is an odd thing to set up music this way, I was a musician and a monitor mixer for bands when you are in the listening position and you are facing the band looking at speakers you are engulfed in it but facing the wrong way, even with side fills as a musician is used to it feels wrong.

@donavabdear 

To me the only way to fix this is to not have the surround channels symmetric.

My room treatments are not symmetric, worked fantastic for me. See "Anthony Grimmani's acoustic recipe.

say you have a signal from 225 degrees on your left behind you. You can’t perceive a phantom center channel between them but that is how Atmos works

My room has a setup less than ideal for back surround speakers so I chose a specific speaker that uses a Harman proprietary technology (HST) to deal with it. It makes it seem like the entire back wall is a speaker in my room:

What do you think?

I can't say what will work for you. What worked for me was following the Dolby specs for speaker setup, measuring, treating my room, using a calibrated mic and upgraded audyssey for DSP, measuring, tweaking and listening, until it met or exceeded what I wanted (both objectively and subjectively). Now I just got that tip about top middle speaker placement from the Trinnov guide so I will tweak. 

@donavabdear 

In  acoustics and photography and many other arts there is something called the rule of thirds, 

I prefer Fibonacci ratios

 I was a musician and a monitor mixer for bands

Talk about a sweet spot. Some of my favorite tracks are sound board mixes from concerts you can get at nugs.net and wolfgangs.com

So I just spen 2 hours redoing my “room perfect” DSP. I played Elton John’s “Sorry seems to be…” it sounded awful in Atmos and much bigger wider deeper in stereo. Is it possible my room sounds better without DSP I don’t even know if I can turn it off or maybe not movies sound great, why did the same song have such a poor showing in Atmos.

Hemispherical speaker are a great idea just like PZM microphones they don’t “see” the plain they are mounted to, makes a lot of sense.

The curve seems ok in real life speakers and microphones sound bad next to a big reflection is simply because of phasing, midrange (1K) usually gets the most noticeable damage this happens if a singer is standing to close to a music stand in the studio it makes a big difference when you lower or remove the stand, if that fails you put a fuzzy blanket over it. That curve is only a single frequency sine wave, music doesn’t look like that, in fact the curves we see on ARK and DSPs like that are just a representation of an averaging algorithm, sound doesn’t look like that only tones do, sound looks like pressure waves. I tried to use a chemical to show sound once, I was working to much, I should pursue it again now, I think I will.

@kota1 i forgot to mention fib. Numbers are cool, I’m curious how you can set them up without something like Protools, do you have something that lets you pan the signal between the speakers? How do you use the fib numbers?

@donavabdear

Is it possible my room sounds better without DSP

DSP is limited in what it can do. If you post your measurements there will be a before and after graph and we can discuss.

I use fib ratios for placing seats, placing panels, not really for equipment.

The HST speakers place the woofer on the back, about 2 inches from the wall, facing it. Two tweeters angled out at left and right directions. It worked better for my room than traditional on walls.

@donavabdear 

Does this give you any ideas for your home atmos studio:

Studio D – Dolby Atmos, Post-production & Mastering

Studio D is a our new mixing, mastering, and music production studio featuring an Avid S6 48-channel digital mixing console with Dolby Atmos 7.4.1 surround sound designed by world-reknowned studio designer John Storyk. 

@donavabdear

You were thinking about dropping six figures on some speakers or getting some new gear. The answer you are looking for is in the post above. How many clients would you get if you took that budget and invested it to have a guy with a rep like Storyk design your home studio?

"The sound guy from Titanic will mix your content in immersive audio in his studio designed by World Renowned Studio Designer_______________ (Storyk, etc)."

That would immediately give you creds in BOTH communities, pro and audiophile. Case closed.

Here is something on fib ratios:

@mikelavigne

So I took the idea from the Trinnov guide you posted to move my top middle surround atmos speaker from above the MLP (where they doubled as VOG for auro 3d) to top rear (right above the surround speakers so they now double as auro 3D surround height channels). Since I moved the speakers I took the opportunity to get new speaker wire (audioquest G-2 in bulk for the long run) and change the amp ( from a parasound Z amp to a Carver AV505), I also installed a new single VOG channel above the MLP. Now my center height, VOG, and top rear speakers are all being driven by the same Carver 5 channel amp. So I fired it up after redoing my calibration and everything sounds smoother. Before I could slightly localize the top middle speakers and now in the new location they blend much better forming that nice immersive bubble. It was a bit of a pain running the speaker wires but it actually looks better to. I’ll need to rewire the new VOG channel next week, I ran out of cable. Well worth the effort and thanks for posting that guide 👍

Before I could slightly localize the top middle speakers and now in the new location they blend much better forming that nice immersive bubble. It was a bit of a pain running the speaker wires but it actually looks better to. I’ll need to rewire the new VOG channel next week, I ran out of cable. Well worth the effort and thanks for posting that guide 👍

@kota1 

you are welcome. great to read that the guide helped. 

helped me too. 

i had been all ready to use the Dolby Atmos ceiling pattern then Trinnov convinced me to switch and i'm very happy too.