IASCA - International Auto Sound Challenge Association
ICE - Refer to In Car Entertainment
iDEN - Refer to Integrated Digital Enhanced Network
Ignition #1 - Refers to a source of power in the vehicle (controlled by a positive switching, non MUX ignition switch) that has +12VDC on it when the ignition keys is in the RUN position and START positions, but has no power in the ACC position.
Ignition #2 - Refers to a source of power in the vehicle (controlled by a positive switching, non MUX ignition switch) that has +12VDC on it when the ignition is in the RUN position, but has no power in the ACC or START positions.
Ignition #2 is not to be confused with electrical function of the ignition switch with terminology many remote starter instructions use to describe their second, sometimes third primary ignition switch connections. In most cases, from a remote starter standpoint - the Ignition #2 and ACC wiring form the vehicle both get connected to the remote starter’s “Accessory” outputs because they don’t need to sty powered while the vehicle starts (whereas Ignition #1 circuits do) and that’s often the only differentiation the remote starter makes with the way its output wiring is labeled.
Ignition Interlock - A device designed to prevent the vehicle’s ignition circuit from operating typically by separating one or more starter wires. This device is installed to prevent drinking and driving. The hand held part of the device will have a breathalyzer attached in order to test the alcohol level of the driver before the vehicle is allowed to start and run. Laws and regulations of ignition interlock systems may very state to state due to the laws surrounding them.
Ignition Kill - A device designed to prevent the vehicle’s ignition circuit from operating. An ignition kill device can work by either interrupting one or both of the primary wires leading to the ignition coil or by shorting out (grounding) the ignition coil’s positive primary wire. Also called “Ignition Disable”.
IM - Refer to Intermodulation
Image Rejection - The rejection of the same signals that can be received at two or more points on the dial of a tuner by a single radio station (ghost, images) . Image Rejection is expressed in decibels, the higher the number the better.
Imaging - The width and definition of a sound stage. Instruments should appear to be coming from their correct positions, relative to the recording.
IMD - Refer to Intermodulation Distortion
Impact Sensor - A sensor designated to detect various degrees of impact or vibration applied to the vehicle and then produce an output to trigger a security system.
Impedance (Z) - In audio this is a measurement of the resistance to the audio current by the voice coil of the speaker. Also refer to Nominal Impedance. When it comes to the electrical side, impedance is the dynamic resistive opposition offered by a device or circuit to the flow of alternating current (AC).
In-Car Entertainment (ICE) - Also called In-vehicle infotainment (IVI), is a collection of hardware and software in automobiles that provides audio or video entertainment. In car entertainment originated with car audio systems that consisted of radios and cassette or CD players, now includes automotive navigation systems, video players, USB and Bluetooth connectivity, Carputers, in-car internet, and WiFi. Once controlled by simple dashboards knobs and dials, ICE systems can include steering wheel audio controls and handsfree voice control.
Inductive Coupling - Radiated noise that is transmitted through a magnetic field to surrounding lines.
Inductance (L) - The property of an electric conductor or circuit that causes an electromotive force to be generated by a change in the current flowing or any other nearby conductors by mutual inductance. These effects are derived from two fundamental observations of physics: a steady current creates a steady magnetic field described by Oersted’s law, and a time-varying magnetic field induces an electromotive force (EMF) in nearby conductors, which is described by Faraday’s law of induction. According to Lenz’s law, a changing electric current through a circuit that contains inductance induces a proportional voltage, which opposes the change in current (self-inductance). The varying field in this circuit may also induce an EMF in neighboring circuits (mutual inductance).
Inductor - Also referred to as a Choke or Coil, this is an electrical component in which impedance increases as the frequency of the AC increases; also known as “coils” that are used in passive crossovers. Inductors are rated in Henries.
Infinite Impulse Response Filter (IIR) - Also referred to as IIR Filter, is a digital filter employing a single stage, through which the signal is passed repeatedly to achieve the desired processing effect. Offers simplicity of design and lower cost than the FIR type.
Infinite Baffle - A loudspeaker baffle of (theoretically) infinite space that has no openings for the passage of sound from the front to the back of the speaker.
Infrared Sensor - A type of spatial sensor that uses infrared energy to detect an object (a hand, arm, or body) entering a protected area. Also refer to Spatial Sensors.
Infrasonic - Refers to sounds or signals whose frequencies are below the normal human hearing range, generally considered to be 20 Hertz.
Input - In audio this is the high-level (speaker) or line level (RCA) signal connections that run into one component from another system component. In security this is any wire on a security system or remote starter designed to accept a signal from some outside source such as the vehicle’s wiring. Door trigger, hood trigger, trunk trigger, foot brake trigger and sensor trigger wires are all inputs.
Input Sensitivity Control - Adjusts the amount of input signal being fed to the amplifier stage to reduce distortion. Also referred to as “Gain.”
Instant Trigger - The term used to describe any trigger input on a security system that is designated to cause the system to respond instantly when triggered.
Insulation - A material that electrically isolates a conductor or thermally isolates an object from its surroundings.
Integrated Digital Enhanced Network (iDEN) - A specialized mobile technology that combines two-way radio, telephone, text messaging and data transmission into one digital network. Introduced by Motorola and used by AirTel Montana, Nextel Communications, Nextel Partners, and Southern LINC Wireless, among others.
Integrity - The expected durability or sturdiness of an installed component or connection.
Intermodulation (IM) - In audio also referred to as Intermodulation Distortion or IMD, is the amplitude modulation of signals containing two or more different frequencies, caused by nonlinearities in a system. Also refer to Intermodulation Distorotion.
Intermodulation Distortion (IMD) - Also referred to as IM Distortion, Intermodulation or IM, is the amplitude modulation of signals containing two or more different frequencies, caused by nonlinearities in a system. The intermodulation between each frequency component will form additional signals at frequencies that are not just at harmonic frequencies (integer multiples) of either, like harmonic distortion, but also at the sum and difference frequencies of the original frequencies and at multiple of those sum and difference frequencies.
In-vehicle infotainment (IVI) - Also referred to as In-Car Entertainment (ICE), is a collection of hardware and software in automobiles that provides audio or video entertainment.
Inventory Turns/Turnover - The number of times inventory is replenished within a particular time, calculated by dividing the cost of goods sold by the average inventory for the period.
Isobaric - Having constant or equal pressure. In audio this is the name of a subwoofer enclosure alignment, also referred to as a “Push-Pull” enclosure. The isobaric configuration was first introduced by Harry F. Olson in the 50’s, and refers to systems in which two or more identical woofers (bass drivers) operate simultaneously with a common body of enclosed air adjoining one side of each diaphragm. In practical applications, they are most often used to improve low-end frequency response without increasing cabinet size, though at the expanse of cost and weight.
Isobarik Enclosure - enclosure where one woofer is buried in the enclosure and a second is mounted up against the first and wired in reverse polarity (there are other variations for Isobarik designs), but this one works best. This allows the effective Vas of both drivers working in this push-pull configuration to be half that of a single identical driver mounted normally. Very small enclosures may be constructed as a result, with increased power handling. Less efficient than other designs, but the push pull configuration greatly reduces second order harmonic distortion. The name Isobarik comes from a term that means "constant pressure". See push-pull.
ISO-DIN Mounting - Refers to a mounting system in which the headunit is mounted behind the dash panel with side brackets, employing factory installed trim panels.