Skip Navigation

Multi-room Music & Video Glossary

The Crutchfield writing team is a group of full-time, in-house copywriters who share a passion for consumer electronics. In addition to creating the articles and videos you find in the Research area of the Crutchfield website, these hard-working and talented people write the informational copy for the products on our website and in the Crutchfield catalog. Our writers constantly research the latest products, technologies, and industry trends, so that we can bring you the most helpful information possible.

More from Crutchfield Writing Team

Click on a letter below to jump to that section of the glossary.



A device that boosts an audio or video signal. The amplifier in a receiver, for example, boosts the incoming audio signal, so that it's powerful enough to move the drivers in your speakers and create sound. Some amplifiers also boost video signals, such as component video or HDMI, allowing them to travel over longer runs of cable without degradation.

Short for "application." You may recognize this term due to the popularity of Apple®'s App Store for the iPhone® and iPod® touch. You'll also see this term used to describe the small applications found on many Internet-ready TVs and other devices. Although the concept is similar, you can't purchase Apple apps for Internet-ready devices from other manufacturers, and you may not be able to expect the same functionality from the same app across different brands. Also see widget.

A feature found in some in-wall volume controls. If you enable auto-muting, it prevents music from automatically playing through connected speakers when you first turn on your system; instead, you have to manually activate the volume control. This feature is popular with outdoor speaker installations, for example, since you'll never accidentally surprise your friends or neighbors with unexpected sound when you fire up your system, regardless of what the volume level was when you turned it off.

back to top


A balun gets its name by converting signals between balanced and unbalanced lines. Balanced cables like CAT-5 can carry signals over much larger distances than unbalanced lines like audio/video cables, because of their superior noise rejection. In a multi-room music or video system, a balun may be used to send audio and/or video signals to another room. You need two baluns — one on either end of the line — to convert the A/V signals from unbalanced A/V connections, to balanced CAT-5 connections, and back again.

back to top


Network cables designed for high-speed, high-integrity data transmission. A lot of people are familiar with CAT-5 cables, since they're used in home and office Ethernet computer networks. These cables can also be used to carry music, video, and control signals in some multi-room systems. You may also see CAT-5e and CAT-6 cables, two more recent versions of CAT-5 that are backwards-compatible with devices designed to work with CAT-5.

CL2 and CL3
Certifications for in-wall speaker wire, indicating that the wire has passed safety tests conducted by the Underwriters Laboratory (UL) and is approved for in-wall and in-ceiling runs. The UL looks at heat generated from current flowing through wire, how quickly the cable will catch and spread fire when exposed to flame, and the wire's susceptibility to damage from external stresses. It's important to use wire labeled CL2 or CL3 for any in-wall speaker wire installation; also, be sure to check your local building and fire code and buy wire accordingly.

See player.

See player.

back to top


DLNA, short for Digital Living Network Alliance, is a collaboration among more than 200 companies, including Sony, Panasonic, Samsung, Microsoft, Cisco, Denon and Yamaha. Their goal is to create products that connect to each other across your home network, regardless of manufacturer, so you can easily enjoy your digital and online content in any room.

While all DLNA-compliant devices are essentially guaranteed to work together, they may not be able to share all types of media. For example, a DLNA-certified TV may be able to display digital photos from a DLNA-certified media server, but not videos.

back to top


A common standard for connecting computers and other devices in a network. Wired Ethernet networks often use CAT-5 cable, while wireless Ethernet networks use Wi-Fi®, a wireless communications standard.

back to top


back to top


back to top


back to top


Impedance magnification
A feature found in some in-wall volume controls. Impedance magnification (IM) allows you to safely connect multiple pairs of speakers to your receiver or amplifier, so long as every connected pair of speakers has a properly set IM volume control. Increasing the impedance of the connected speakers makes them more resistant to the flow of current, which prevents them from damaging your amplifier by drawing too much power.

Components labeled "Internet-ready," like some TVs, Blu-ray players, and home theater systems, can connect to your home network to access limited online content. All Internet-ready components have an Ethernet port for making a wired connection, and some can also connect wirelessly via built-in Wi-Fi® capability or an optional USB adapter. For example, a growing number of Internet-ready TVs let you play movies from services like Netflix®, BlockBuster™, or Amazon Video On Demand™.

Keep in mind that you won't be able to browse the Internet the way you do on your computer — you'll only be able to access specific sites and information based on the widgets that are included with your TV. Different manufacturers provide access to different Internet sites and services, and sometimes these capabilities can be enhanced by firmware updates that the manufacturer provides. Besides movie services, common examples include weather, news, social media updates, and sports scores.

IR flasher
Infrared light-emitting devices that work as part of an IR (infrared) repeater system, which can extend your remote control capability from one room to multiple rooms in your home. IR flashers pass commands from IR sensors to audio/video components. An IR flasher looks like a regular cable with two distinctly different ends. One end plugs into an IR hub. The other end is the IR emitter; it sits in front of a component's IR sensor, which is located on the front-panel.

IR hub
The brain of an IR repeater system, which can extend your remote control capability from one room to multiple rooms in your home. An IR hub routes incoming signals from IR sensors to IR flashers, which in turn pass them on to your A/V gear.

IR repeater system
A system that allows you to send IR (infrared) control signals to your A/V gear from a remote room. It typically consists of IR sensors, IR flashers, and IR hub. See our article on Remote Control Setups for Multi-room Systems for more information.

IR sensor
A sensor that picks up infrared (IR) signals emitted by a remote control. TVs, DVD players, cable boxes and most other audio/video components include an IR sensor on the front allowing you to deliver commands remotely, such as "volume down" or "channel up." Stand-alone IR sensors, along with other devices in an IR repeater system, can also be used to control audio/video gear from a remote room in a multi-room system. Some in-wall volume controls also include built-in IR sensors to use as part of a remote control extender system.

back to top


back to top


back to top


Line-level inputs and outputs
See preamp inputs and outputs.

back to top


A term used to describe a system that delivers audio, and possibly video, to multiple rooms or areas in a home.

A term used to describe a system that allows users to choose from multiple A/V sources, such as a DVD player and FM tuner.

A term used to describe a system that allows users to enjoy different A/V sources in different rooms or areas around their house at the same time. For example, the master bedroom and master bath might be one zone, while the kitchen and breakfast nook are another.

back to top


back to top


back to top


Preamp inputs and outputs
RCA-style jacks that deliver an unamplified stereo audio signal. These outputs are often used to pass stereo audio to an amplifier or receiver in a second room.

A term sometimes used in multi-room music and video systems to describe the device on the receiving end of the signal. The player is typically responsible for accepting the incoming signal and routing its next destination — like a TV screen or a pair of in-ceiling speakers. Players also typically offer some form of control over your remote system, such as source selection and volume adjustment. A player may also be referred to as a "client," "controller," or "streamer," and can be designed for in-wall installation or for placement on a table or shelf.

back to top


back to top


An audio component that combines a preamplifier, amplifier, and an AM/FM tuner in a single chassis. Home theater receivers feature five or more channels of amplification, and many include preamp and/or speaker level outputs for a multi-room system. A stereo receiver offers two channels of amplification, and is sometimes used in conjunction with speaker selectors and in-wall volume controls in a multi-room system. See our article on Powering Your Multi-room System for more information.

Remote control extender system
A system that allows you to control the A/V gear in a multi-room system from remote rooms. Options include RF (radio frequency) remote controls, and wireless and wired IR repeater systems. See our article on Remote Control Setups for Multi-room Systems for more information.

Whether wired or wireless, routers serve as the Internet access point for all your connected devices. Lots of today's home A/V and portable gear can connect to your home network, including some multi-room music and video components.

back to top


A device that allows you to select one or more connected components, sometimes also called a "switcher" or "distribution amplifier." Speaker selectors may be part of a multi-room music system. They allow you to activate all of the connected speakers, or just one or two pairs, whatever you like. See Powering Your Multi-room System for more info. Most audio/video source distribution amplifiers allow you to connect between two and four A/V components, and send a signal from one of them to your system. Some can send A/V signals to two TVs and/or sound systems at once, which can be a great feature for multi-room A/V systems.

In a multi-room music or video system, a server is a device that stores audio and video content on its hard drive, then "serves" up requested content to clients around your home. For some people, a family computer that stores lots of digital music might be a server. Others prefer to use a dedicated server for distributing music and video, and save their regular computer for web surfing and other everyday tasks.

Speaker level
Speaker connections that deliver an amplified stereo audio signal. These outputs are often used to pass stereo audio to a pair of speakers in a second room. Unlike preamp connections, you won't need to use an additional amplifier.

The act of sending media from one device (the player or client) to another (the server) over a wired or wireless network, depending on the capabilities of the devices involved. The faster and stronger the network connection, the more reliable the streaming process will be.

See selector.

back to top


back to top


See CL2 and CL3.

back to top


back to top


Internet-ready components often offer widgets or "apps," which are symbols or pictures that stand for applications giving you access to a limited range of online content. Common widgets include ones for streaming movies from online providers like Netflix®; checking news, weather, and sports; and connecting to popular social networking sites like Facebook® and Flickr®.

Keep in mind that you may not have full access to these services as you would from your computer. For example, an Internet-ready TV may have a widget for Facebook with their iconic logo, which allows you to view status updates and friend's profiles from the comfort of your sofa. You may not, however, be able to update your status (depending on the manufacturer) or make tweaky changes to your privacy settings using your TV's Facebook widget.

A wired multi-room system must be connected with cables, often installed inside walls and ceilings for a clean, professional look. Wired systems can use a variety of cables, such as speaker wire, audio/video interconnects, and CAT-5. The wiring you need will depend on the requirements of a specific system. Wired systems are often popular choices for homes that are still under construction or extensive renovation, since installing new in-wall wiring can be difficult after the sheetrock and installation are up.

A wireless multi-room system can send audio and video around your home without wired connections. Some systems use Wi-Fi®, a common wireless standard, while others create their own proprietary wireless network. Wireless systems are often popular choices for homes that have already been finished, since installing new in-wall wiring can be difficult after the sheetrock is up.

You'll see this used as a catch-all term to describe multi-room, multi-source, and multi-zone systems. Common types of systems that fall under this umbrella include multi-room/multi-source and multi-room/multi-zone. Multi-room/multi-source systems let you choose from more than one A/V source and play it in more than one room at the same time. A multi-room/multi-zone system lets you choose from more than one A/V source, play it in more than one room, and play different sources in different rooms at the same time.

back to top


back to top


back to top


back to top

Ask an expert advisor

No pressure, no commission — just lots of good advice from our highly trained staff.