The last few months have seen some exciting developments in the field of surround sound audio. A new surround-sound format has emerged which is object-based rather than channel-based, and it can support up to 34 speakers.
What exactly does that mean? Where traditional surround-sound formats are heard on speaker channels, this new format is based on audio objects and their specific sounds that are heard around the room, creating an immersive experience. Immersive object-based audio is a development that has home technology professionals very excited. It offers opportunities for upgrades and is being hailed as the greatest advancement since Dolby Digital.
All of this may seem rather intimidating to residential integrators, especially if they don’t currently offer any audio services; as other home technology professionals “geek out” over the specs, you may feel it’s over your head. It may be time to up your audio game.
Audio is very complex, at the least. If you would like a history lesson or some great breakdowns of how sounds works, we recommend you purchase the book, Fundamentals of Residential Electronics or visit cedia.net/training and check out the Audio for Technicians course.
If you are new to audio, then knowing the types of speakers is a good place to start. There are a variety of manufacturers and types of speakers and you should be able to distinguish them before trying to install them in a client’s home.
In-wall/in-ceiling speakers, or “architectural speakers” often are used in distributed audio, or in theater situations where there is a desire to make the speakers inconspicuous. This type of speaker is designed to be installed flush with the wall or ceiling surface and can sound very good. Tilt-able transducers are preferred because they allow the sound to be aimed, putting the listener on-axis with the speaker.
Most manufacturers that produce architectural-style speakers also offer back-boxes that can be used with their in-wall or in-ceiling speakers. Benefits include increased speaker performance, added protection of speaker, reduced chance for speaker rattles and vibrations, reduced transmission of sound to adjoining spaces and increased fire safety.
Home Theater Speaker Types
Regardless of the type speakers used in a home theater, they ideally should be from the same manufacturer and should be the same model class so they will sound basically the same and have the same tonal quality. Some speakers are designed to play a specific role in a home theater system. It is often not practical to have all full-range speakers identical, so special speakers are offered to be used for the center channel and surround/rear channels.
Center channel speakers are designed to have a similar tonality to other speakers in the system, but often are configured horizontally, making them ideal for placement directly above or below the display.
Surround speakers often just monopole two ways, but sometimes more specialized designs are chosen for a more enveloping surround experience. They are usually in-wall or on-wall types with transducers aimed in different directions. If these transducers are wired out of phase, the design is known as di-polar; if in phase, bi-polar. Some are switchable.
Subwoofers can be utilized as an enhancement to a two-channel system or even a distributed audio zone. But the most widespread use is in home theater and media rooms, where the deep bass plays such a vital role in the experience.
Subwoofer types include free-standing self-powered speakers, and in-wall designs that require the amplifier to be housed with the rest of the equipment. Self-powered subs require a coaxial feed for analog audio, and an outlet for AV power. Passive subs such as in-walls are fed with speaker cable from the remote amplifier.
If you are interested in learning about audio including speaker placement, distributed audio and more, the Fundamentals of Residential Electronics book offered by CEDIA covers these topics and many others. Visit cedia.net/train.