Dolby Atmos setups are popular among audiophiles and cinema lovers alike. In addition to accommodating up to 128 tracks for theater-quality replication, the Atmos format has become increasingly common at home.
After they were introduced in 2012, Atmos technologies quickly fulfilled roles in a range of audio products and media formats, such as Blu-ray.
Understanding Surround Sound
Surround sound creates the auditory illusion that the listener is there in the midst of the action. By using multiple speakers and channels, or audio signal paths, surround sound can make music clearer or ensure that movie sound effects actually fit what’s happening onscreen.
Surround sound systems are generally classified by the number of speaker-channel pairs they include.
More often than not, this is written as a group of numbers separated by periods. The different numbers represent the number of speakers in each channel. Channels are usually written in a standard order with full-range speakers before bass subwoofers.
The Ins and Outs of Dolby Atmos
The Dolby Atmos specification often includes a third number. With a Fluance Dolby Atmos setup, this signifies the total number of ceiling mounted speakers in the system.
What makes a Dolby Atmos home cinema system different from other hardware? These devices include custom processors that can replicate standard 5.1 or 7.1 surround sound, but they’re also endowed with extra mixing capacity. The vertical audio channel created by the ceiling mounted speakers is ideal for replicating sounds above and below the listener instead of just panning them from left to right.
From Classic Surround Sound to Dolby Atmos
It’s fairly easy to choose a Dolby Atmos speaker setup. Simply add the number of ceiling mounted speakers being installed to the old surround sound standard. For instance, adding two new ceiling mounted speakers to a 7.1 surround sound system creates a 7.1.2 Atmos system.
Atmos standards provide for dozens of overhead speakers although most homeowners just use the recommended four. Why does the number and placement of speakers matter? Dolby’s surround sound is designed to compensate for spacing and speaker locations:
It attempts to reproduce sounds as if they were real objects with physical positions. For this to work, the system needs to know the precise number of speakers being used.
Getting Started With a Dolby Atmos Setup
Instead of using completely isolated channels, Atmos actively mixes sounds to produce the best possible output. It can even adapt to a given speaker arrangement on the fly to create fuller audio.
Atmos supports way more features than most traditional surround sound setups do. Nonetheless, Dolby decided to make it easy to integrate the technology with legacy hardware. As such, Atmos stereos function equally well with specialty Atmos-enabled speakers and their conventional counterparts.
Common Dolby Atmos Setups
According to Dolby, the majority of A/V receivers that work with Atmos have a channel called “HEIGHT” or something similar. This is what the overhead speakers connect to, so homeowners should ensure that the receiver being used has the appropriate number of channels.
If there’s no HEIGHT channel, in some cases, A/V receivers can be configured to use specific channels for vertically panned sounds, so homeowners can consult the device instructions to configure the settings properly.
As with any surround sound system, a Dolby Atmos setup should be built around the viewer or listener’s ideal location. For instance, those who plan on building entertainment dens often install their full-range speakers on shelves or stands so they’re at head height when people sit on the couch.
Users can choose an appropriate height, or listener level, at their discretion. All speakers at this level, however, should be at the exact same height. In most standard Dolby Atmos setups, listener level is set at 3.9 feet, or 1.2 meters.
For some users, space constraints prevent the rear and front speakers from being placed at the same height. While Dolby Atmos can function properly with elevated rear speakers, they can’t be more than 1.25 times higher than the front ones. For best results, the speakers should all be the same distance from the listener.
Dolby Configurations Explained
A 5.1.2 system uses two ceiling mounted speakers in addition to a normal 5.1 setup.
A 5.1.4 system uses four ceiling mounted speakers in addition to a normal 5.1 setup.
A 7.1.2 system uses two ceiling mounted speakers in addition to a normal 7.1 setup.
A 7.1.4 system uses four ceiling mounted speakers in addition to a normal 7.1 setup.
A 9.1.2 system uses two ceiling mounted speakers, or two Dolby Atmos enabled speakers in addition to a normal 9.1 setup.
Diagrams of all the supported Dolby Atmos configurations using 7.1 through 11.1 channels. Images sourced from Dolby.
Overhead Fluance Speakers and Dolby Atmos Audio
Atmos audio streams work better with matched speakers. In most cases, users pick overhead speakers with sound reproduction profiles that match their listener-level units, but there are also other factors to consider.
Speakers emit sound in cones called dispersion patterns. The volume is usually concentrated in the center of the cone, so the same song may sound louder to a user standing right in front of the speaker than it does to another user standing off to the side. Different speakers have unique dispersion patterns; those used for Dolby Atmos HEIGHT channels should ideally have wider cones. This makes up for the fact that most home theaters don’t have as many overhead channels as cinemas do, and it also helps smooth out the sound.
When placing overhead speakers, those with dispersion cones of 45 degrees or wider can generally be pointed straight downward. With speakers that produce sound in a more limited pattern, however, it may be necessary to point the units at the listener. Finally, overhead speakers should be at least two times higher than listener level, but they can hang below the ceiling if necessary.
Building a Dolby Atmos setup?
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