or 'I Upgraded My Home Theater System, But I Can't Hear the Benefits. Why?'

originally published Aug 25, 2004 by Ray Adkins

A beginners speaker placement guide for a 2 channel system to a 7.2.4 Dolby Atmos system and everything in between.MOVIE OF THE WEEK:Joker 4K: https://www.am. The configurations noted in this speaker setup guide are illustrative. 5.1 Home Theater Speaker Placement. 5.1.2 Dolby Atmos Enabled Speaker Placement. Optimize your sound system that includes Dolby Atmos technology with this step-by-step guide to the best speaker setup. ## 5.1.2 Atmos Home Theater Overhead Speaker Placement. Side view of a 5.1. The LG SJ9 is a 5.1.2 channel soundbar that is compatible with Dolby Atmos. Instead of being confined to a certain number of channels, Dolby Atmos creates an atmosphere of sound that blankets you for a more realistic and immersive experience. The video shows 5.1.2 Dolby Atmos speaker placement for perfect home-theatre setup and includes 5.1.2 surround sound test audio for easy setup of 6+2 channel. Q Per Dolby, using two height speakers in a 5.1.2 configuration is good enough to get Atmos (see this earlier Ask S&V exchange on the subject). However, an installation using dual height speakers is considered bare bones—Dolby recommends using four height speakers to get a more enveloping, realistic experience.

We received numerous emails from fellow Audioholics who recently upgraded their home theater systems to find that the sonic improvements were less than expected. This is a topic that comes up more often than you think when the Home Theater enthusiast upgrades his or her equipment. There are a few factors you need to consider to solve this issue. First you may need to get used to the new receiver sounding different. If it's been a while since you've upgraded, you'll find that most current A/V receivers come with some sort of auto-calibration software. Systems like Audyssey MultEQ, Yamaha's YPAO, and Pioneer's MCACC will apply filters to your speakers in order to counteract the negative effects of the room (resonances, peaks, dips, etc.). Newer receivers will also support the latest codecs, i.e. Dolby TrueHD, DTS-HD, and possibly even cutting edge formats like Dolby Atmos and Auro-3D. These discrete surround formats are light years ahead of the old Prologic and even lossy Dolby Digital codecs of yesteryear.

To get the most out of your system, you should first define how many speakers you're able to place into your living room from a budgetary and aesthetic standpoint. Please watch our Youtube video where we discuss this topic in greater detail before proceeding to read the rest of this article.

How Many Speakers Do You Need for a Great Home Surround Experience?

To break it down, since Dolby Digital and DTS hit the home theater market back in the 1990's, 5.1 has been the standard surround sound layout. We consider this the minimum needed to achieve an excellent surround experience. Even with the advent of newer 3D sound formats such as Dolby Atmos, the base 5.1 channels continue to receive the lion's share of the content. To put it simply: we don't recommend skimping on the quality of these channels in the name of quantity.

The standard 5.1 layout diagram.

Best 5.1.2 Atmos Speaker Placement

So what about Atmos? At the moment, the most commonly supported setups are 5.1.2, 5.1.4, 7.1.2, and 7.1.4. These add two or four overhead speakers (or Atmos Elevation speakers) to the standard 5.1 and 7.1 layouts. If you're doing a new theater build, we would definitely recommend at least pre-wiring for a quartet of in-ceiling speakers. To learn more about Atmos (including placement diagrams), see our Dolby Atmos For Home Theater Explained article. For now, we'll focus on getting basic 5.1 right.

Here is a list of items you will need to do help you properly set up and calibrate your home theater system:

• 1 25ft tape measure
• 1 pair of rubber pie shaped door stops (Home Depot)
• 1 package small square rubber stick-on feet (Home Depot)

Step 1: Center Speaker Positioning

First stick two rubber feet on the bottom front of your center speaker. Then place the pie shaped doorstops under the back of the center so the back is angled down toward the listening position. Next, place the laser pointer on the top of the center speaker pointed at the listening position. Then aim and adjust the beam of the laser pointer so it is just above the ear level at the listening position. Adjust the rubber door stops until the correct height is obtained. This effectively aims the tweeter at the listening position between your ears.

Step 2: Main Speakers Positioning

Position your front main speakers at least a foot off each back and side wall and you are close to the 'Golden Triangle Rule' ( Example: speakers 8ft apart from listening position and 8 ft back). Make sure that the speakers are the same distance off the back wall with the tape measure, then place the laser pointer on the inside panel of the speaker enclosure at the height of the tweeter.

With the laser pointer beam active, rotate the speaker inward until the laser pointer beam is about 6' away (outside) from the center of your listening position. This will effectively toe in the speaker to a close position according to the dispersion patterns of your speakers. If your speakers have an unusually wide dispersion pattern, you may wish to experiment with the degree of toe in for optimal performance.

For installs where there are multiple seats, we recommend an 80% triangle rule (IE. speaker distance is 80% of distance to seated area). So if your seated area is 10ft away, the front speakers should be 8ft apart. Less toe-in would be required, thus allowing for broader dispersion while also taking advantage of sidewall early reflections which are beneficial to the listening experience.

Step 3: Surround Sound Speakers Positioning

Bipolar/Dipole speakers which are typically utilized for surrounds usually perform best when placed on the side walls directly beside or slightly behind the seated listening position and at approximately 18-28' above the seated ear level position. This ensures a relatively diffuse sound field and makes localizing the surround speakers much more difficult.

Quadpolar surrounds, similar to Bipoles, usually perform best when placed on sidewalls, but closer to the backwalls, for rear wall reflection of the side mounted tweeter. Their height should be about 4-6 feet above the seated position, but greater than 1 foot away from the ceiling to not obscure the top mounted woofer.

Direct Radiating surrounds usually perform best when placed behind and slightly higher than the listening position, spread apart the same distance as the mains and slightly toed in.

Step 4: Subwoofer Positioning

Subwoofer placement is adequately covered in our article: Crawling for Bass.

Step 5: Speaker Configuration Set-Up In The A/V Receiver

As mentioned above, most modern A/V receivers will feature some sort of auto-calibration system. These will automatically determine speaker distance relative to the main listening position, level match your speakers and subwoofer, and set appropriate crossovers. The systems will also ensure there aren't any issues with electrical and acoustic phase. We recommend double-checking these settings, as we've found crossover settings in particular to be problematic. To start, we suggest setting all speakers to small, with an 80Hz crossover to the subwoofer. For a more in-depth look at bass management, we recommend: Bass Management Basics: Settings Made Simple. You can double check speaker distances with a tape measure, but note if the subwoofer distance reported is higher than expected, this may be due to DSP processing within the sub's amplifier which may delay the signal slightly.

Last but not least, it's time to double-check that the speakers are properly level matched. For this, place your SPL Meter at the listening position at ear level with the Mic end pointed toward the ceiling. Select 'C' weighting, response slow then, turn the dB dial to 70. Activate the internal pink noise generator of your Receiver and select manual test tone. Now adjust each speaker to +75 dB reference. When you are adjusting the surrounds make sure your body is not in a direct path of the speaker and make sure the house is quiet. When doing the calibration, only the test tone should be heard (A/C, ceiling fans, ect. should be turned off).

Step 6: Enjoy!

Put in a good flick with lots of hard simultaneous pans and dialog, and plenty of dynamic swings. 'Contact' Lift off chapter or 'The Phantom Menace' Pod race, or 'U571' Depth Charges, work well. IF YOU DON'T SAY WOW AFTER THE VIEWING, START OVER!

Both DTS:X and Dolby Atmos are relatively new audio formats that utilize objects instead of classical channel layouts. The metadata for the objects and their position in three dimensional space tag along either DTS HD/MA or Dolby TrueHD/Dolby Digital Plus. An Atmos or DTS:X processor then uses this metadata to position the sound across the available channels. The idea behind this is that regardless of the theater or home theaters setup the processor can accurately present the location of a sound regardless of both the number of channels and the configuration of those channels. In theory it shouldn’t matter if you are using 5.1.2, 5.1.4, 7.1.4 or 24.1.10, you should get the same relative imaging across the sound field. In the cinema, Atmos offers support for up to 64 individual channels, and up to 34 in a home theater. My guess is the majority of HT enthusiasts will be pushing both budget and space constraints with a 7.1 channel or 9.1 channel system, let alone a 34 channel system, but, it’s always nice to have the option (assuming AVRs and processors support that many channels). DTS:X supports a maximum of 30.2 channels in the cinema, and 11.2 in the home.

One of the things that’s supposed to set DTS:X apart from Atmos is their claim that it can support any channel layout. In theory, you should be set up your system however you want (within the limits of your AVR’s configurations) and it should work regardless, Unlike Atmos’ prescribed layouts. One benefit of this is that it should be compatible with the Auro 3D 10.1 layout, which Atmos is not. Atmos does not support the Voice of God channel (a single overhead speaker) nor does it support Side Heights or Front Top Center. DTS:X should be able to. Dolby doesn’t come right out and say their system supports many different speaker layouts, but it clearly does, considering it can be scaled from 8 channels to 34 in the home. In addition to height/overhead channels, front wides, rear wides, rear centers, and everything in between is supported outside of placing height channels above the surrounds. Atmos requires height channels, while DTS:X does not. This is good, considering not everybody has the ability or desire to add overhead speakers (and dolby enabled speakers really suck in my experience), and object based audio definitely sounds much more precise than a simple 7.1 mix utilizing panning/phase manipulation.

The biggest question I have is does it actually work the way DTS:X claims, and how does the ability to scale to different layouts compare between Atmos and DTS:X? That’s what I set out to discover. Currently I have an Onkyo TX NR-656. It’s a 7.2 receiver with both DTS:X decoding and Atmos decoding capabilities. Obviously, it only allows me to use one pair of height speakers, either Top Front, Top Middle, Top Rear, Rear Height, and Top Height. Dolby recommends using Top Middle speakers for a 5.1.2 config, and that’s what I had originally set my system up with, similar to this:

Before we delve into whether or not DTS:X really works with any layout, let’s look at what DTS:X classical layouts look like.

DTS has no recommendations on how to configure your system on their site for DTS:X, obviously, if it’s supposed to be compatible with any layout, you shouldn’t need to follow any prescribed setup. But what about the studios who mix in DTS:X? What setup are they using? I managed to find a few pictures of a studio setup here.

Looks to me like classic 11.1 with 7 bed channels and 4 height (not top) channels.

How will this translate to my 5.1.2 setup with a single pair of Top Middle speakers? To find out, I first used the DTS:X Object Emulator. It’s basically a floating ball that moves around different channel layouts, the sound follows the ball. You can see a preview of it here (in stereo obviously). The demo file can be downloaded from The Digital Theater.

The first thing I noticed, DTS:X does a really good job of making 5.1 sound more like 7.1, Atmos does this too. In Dolby Atmos’ guidelines for home theater, 5.1.x setups specify that the surrounds are placed at 110 degrees vs 90 degrees, and directly at ear level. Originally it was recommended that the surrounds be placed about 2 feet above ear level for traditional 5.1 and 7.1, however, now that overhead speakers have been added, this is no longer necessary and actually detrimental to getting good separation between overhead sounds and floor sounds. With traditional 5.1, a 7.1 track is downmixed to 5.1 by simply folding the rear channels into the surrounds, In DTS:X and in Atmos, things passing through the rear channels are phantomed between the surrounds and the appropriate phase delay is added, so it does sound like it’s coming from behind, similar to how a phantom center channel appears in classic stereo. Off to a good start, we’re getting rear channel/surround channel seperation with two surrounds.

What about overhead sounds though? How does that translate to my Top Middle Atmos configuration? As you can see from the Object Emulator Demo, there is no Top Middle speakers, only Rear Height, and Front Height.

Right off the bat I’m assuming that the DTS:X software is going to create a Phantom image for the front and rear heights by mixing it between the fronts/surrounds and top middle speakers. Turns out that wasn’t the case. As the ball passes by the front and rear heights, the top middle speakers remain silent, and the sound is mixed exclusively in the front and surround bed channels. The only time I hear anything coming from overhead is when the ball is directly in the middle above. Not good. Quite a bit of height information is lost this way. What if a helicopter in a movie is approaching from the front or rear? Unless it passes overhead, you’re not going to hear it from the heights at all. With Atmos, I’ve not had any trouble like this. All height information is mixed into the top middle speakers and then phantomed between those and either the front or surrounds, the way that it should be.

This got me thinking, perhaps DTS:X simply doesn’t jive well with a top middle configuration. To see if this was the case, I simply changed my configuration via the setup menu in my receiver to front height and repeated the demo. I immediately noticed a whole lot more sound coming from the height speakers, not just when it passed through the front heights, but also the rear heights. As the ball approached the rear heights, the sound was mixed between the rear speakers and heights, with the heights changing phase as the ball approached the rear. The same thing happened when I reconfigured the heights to rear heights. What about top front and top rear? Same thing, it works.

I set the config back to top middle and decided to try a movie mixed in DTS:X. For this, I picked The Girl on the Train. I watched the entire movie with the top middle configuration, and not once did I ever hear anything come from the height speakers. Changing them to front or rear heights again, solved this problem, with plenty of height information coming from the top.

From this, we can conclude that DTS:X certainly doesn’t just work with all configurations. Perhaps with a greater number of speakers, a top middle pair would work well as an addon, but only with front and rear heights as well. In all configurations, I have yet to see top middle speakers in any studio configuration for DTS:X, and it’s obvious DTS had height speakers, rather than top speakers, in mind when designing the format. This is certainly something to keep in mind when setting up a 5.1.2 system.

It worth noting that Atmos seems to work well no matter what setup I choose, Top front/middle/rear, or Front height/rear. Sounds come from the appropriate location. With this in mind, I would suggest designing an Atmos/DTS:X system that includes only a single pair of height speakers with either Top fronts, or Front heights for maximum compatibility.

Dolby 5.1.2 Speaker Placement

Aside from the top middle problem, there is no discernable difference between the way the two work when it comes to panning sounds across a 3D sound stage.

Dolby Atmos 5.1 2 Height Speaker Placement

In part II, we will look at the differences and compare between the two Upmixing modes, Dolby Surround and DTS: Neural X.