A representation of how alternating current varies over time. The simplest and most familiar waveform is the sine wave, but any electrical signal of any complexity will also have a waveform.

The distance that a wave propagated in space or along a wire travels while going through a single cycle (360°). At room temperature one wavelength at 100Hz is around 11 feet, while at 10kHz the distance is reduced to about 1.3 inches. An important detail that needs to be understood in the design of acoustic spaces.

A means by which the laboratory measurements of the performance of a piece of audio equipment are modified to better take into account human aural perception. This generally delivers slightly better specifications. For example, "a-weighting" is a curve that is applied to the measurement of sound pressure levels that compensate for the way the human ear perceives loudness.

A single element antenna that can be directly attached to a wireless transmitter or receiver. The short flexible antennas found on handheld two-way radios and cell phones are examples of this type of antennas.

A sound that contains every frequency within the range of human hearing in equal amounts.

Jitter is the deviation of some aspect of the pulses in a digital signal. In audio applications, Analog to Digital converters are one of the most critical components that are susceptible to jitter. Using an internal or external clock, an A/D converter "slices" an incoming audio signal into a number of pulses that digitally conforms to the original source.

In digital audio, the term is used to define the number of bits a digital device uses to process audio. While sampling frequency determines the outer frequency limits that a piece of hardware is capable of processing, bit depth refers to the dynamic range that can be captured during recording.

Yamaha's answer to Roland's GS system. Both systems are attempts to enhance the General MIDI protocol, providing additional banks of patches and further editing functionality.

XY stereo set-up is a coincidence stereo technique using two cardioid microphones in the same point and angled at 90° to produce a stereo image. Theoretically, the two microphone capsules need to be at exactly the same point in space to avoid any phase problems due to the distance between the capsules.

A type of directive antenna that provides moderate to high gain over a relatively limited frequency range. Commonly used in communications when the operating frequency is above 10MHz. This type of antenna is popular among Amateur Radio and Citizens Band radio operators.