| A | B |
|---|
| 2.1 | Speaker setup consisting of two stereo speakers combined with a subwoofer. |
| 5.1 | Four satellite speakers plus a center speaker and a subwoofer. |
| AC’97 | Sound card standard for lower-end audio devices; created when most folks listened to stereo sound at best. |
| amplitude | Loudness of a sound card. |
| autosensing | Better quality sound cards use autosensing to detect a device plugged into a port and to adapt the features of that port. |
| A/V sync | Process of synchronizing audio and video. |
| bit depth | Number of colors a video card is capable of producing. Common bit depths are q6-bit and 32-bit, representing 65,536 colors and 16.7 million colors, respectively. |
| CD quality | CD-quality audio has a sample rate of 44.4 KHz and a bit rate of 128 bits. |
| codec | Software that compresses or decompresses media streams. |
| container file | File containing two or more separate, compressed tracks, typically an audio and a moving picture track. Also known as a wrapper. |
| decibels | Unit of measurement typically associated with sound. The higher the number of decibels, the louder the sound. |
| Digital Theatre Systems (DTS) | Technology for sound reductions and channeling methods, similar to Dolby Digital. |
| DirectSound3D (DS3D) | Introduced with DirectX 3.0, DS3D is a command set used to create positional audio, or sounds that appear to come from in front, in back, or to the side of a user. |
| DirectX | Set of APIs enabling programs to control multimedia, such as sound, video, and graphics. Used in Windows Vista to draw the Aero desktop. |
| Dolby Digital | Technology for sound reductions and channeling methods used for digital audio. |
| environmental audio extensions (EAX) | 3-D sound technology developed by Creative Labs but now supported by most sound cards. |
| FM synthesis | Producing sound by electronic emulation of various instruments to more-or-less produce music and other sound effects. |
| frequency | Measure of a sound’s tone, either high or low |
| Intel High Definition Audio (HDA) | Intel-Designed standard to support features such as true surround sound with many discrete speakers. |
| monaural | Describes recording tracks form one source (microphone) as opposed to stereo, which uses two sources. |
| MP3 | Short for MPEG, Layer 3. MP3 is a type of compression used specifically for turning high-quality digital audio files into much smaller, yet similar sounding, files. |
| musical instrument digital interface (MIDI) | Interface between a computer and a device for simulating musical instruments. Rather than sending large sound samples, a computer can simply send “instructions” to the instrument describing pitch, tone, and a duration of a sound. MIDI files are therefore very efficient. Because a MIDI file is made up of a set of instructions rather than a copy of the sound, modifying each component of the file is easy. Additionally, it is possible to program many channels, or “voices” of music to be played simultaneously, creating symphonic sound. |
| polyphony | Number of instruments a sound card can play at once |
| positional audio | Range of commands for a sound card to place a sound anywhere in 3-D space. |
| pulse code modulation (PCM) | Sound format developed in the 1960s to carry telephone calls over the first digital lines |
| sampling | Capturing sound waves in electronic format |
| satellites | Two or more standard stereo speakers to be combined with a subwoofer for a speaker system. |
| signal-to-noise ratio | Measure that describes the relative quality of an input port. |
| Sony/Philips digital interface (S/PDIF) | Digital audio connector found on many sound cards. Users can connect their computers directly to a 5.1 speaker system or receiver. S/PDIF comes in both a coaxial and an optical version. |
| stereo | Describes recording tracks from two sources (microphones) as opposed to monaural, which uses one source. |
| streaming media | Broadcast of data that is played on your computer and immediately discarded. |
| subwoofer | Powerful speaker capable of producing extremely low-frequency sounds. |
| timbre | Qualities that differentiate the same note played on different instruments. |
| TV tuner | Typically an add-on device that allows users to watch television on a computer. |
| video capture | Computer jargon for the recording of video information, such as TV shows or movies. |
| wave table synthesis | Technique that supplanted FM synthesis, wherein recordings of actual instruments or other sounds are embedded in the sound card as WAV files. When a particular not from a particular instrument or voice is requested, the sound processor grabs the appropriate prerecorded WAV file from its memory and adjusts it to match the specific sound and timing requested. |
| wrapper | Another word for container file |
