Reference

Car Audio Glossary

Plain-language definitions for terms used by the calculators and six installation guides.

Clipping
Waveform distortion that occurs when a device is asked to produce more output voltage than its power supply or signal path can provide cleanly.
Crossover
A filter that limits the frequency range sent to a driver. A high-pass filter blocks frequencies below its setting; a low-pass filter blocks frequencies above it.
DVC
Dual voice coil: one loudspeaker motor with two separate voice coils. The coils must be wired so the amplifier sees a supported final load.
Gain
An amplifier input-sensitivity control used to match the source signal voltage to the amplifier. It is not a power or volume control.
Impedance
Frequency-dependent opposition to AC current, measured in ohms. A speaker's nominal impedance is a category, not a constant resistance at every frequency.
Net enclosure volume
Usable internal air space after subtracting driver, port, bracing, and hardware displacement.
OFC
Oxygen-free copper. In car-audio wiring it identifies copper conductor rather than copper-clad aluminum; actual strand area and cable construction still matter.
RMS power
A continuous power rating under stated test conditions. Compare ratings only when impedance, voltage, distortion, and test method are compatible.
SVC
Single voice coil: a loudspeaker with one voice coil and one pair of terminals.
Thiele/Small parameters
A set of measured electromechanical driver parameters used to model low-frequency behavior and enclosure alignment.
Voltage drop
The difference in voltage between two points while current is flowing. Measuring drop under load reveals resistance that a continuity beep can miss.
Xmax
A manufacturer's specified linear-excursion value. Definitions and measurement methods can differ, so compare only like specifications.