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1. IHF-Institute of High Fidelity - the premier institution for high fidelity whose standards have come to be universally recognized in application to the operation and design of sound re-enforcement and reproduction equipment.
Submitted on Monday, July 10, 2006 1:45:22 PM

2. Imaging
Listening term. A good stereo system can provide a stereo image that has width, depth and height. The best imaging systems will define a nearly holographic re-creation of the original sound
Submitted on Friday, January 13, 2006 1:45:22 PM

3. Imaging:
Imaging describes the extent to which an audio system reproduces the directional cues that enable the listener to locate the instruments and vocalists as they were positioned during recording and mixing (See also Soundstage below). Good imaging creates a listening experience that seems natural and lifelike. Since directional cues in sound come mainly in the higher frequencies, the key to attaining the best possible imaging is to have equal and unobstructed path lengths between the tweeters and the listener's ears. That's one of the reasons why matched component speakers, with their versatile tweeter placement, sound as good as they do.
Submitted on Friday, August 11, 2006 1:45:22 PM

4. Imaging
is a description of the illusion of being able to locate certain sounds as "coming from" certain places. If you have a system with good imaging, the sound should seem to come from different distinct instruments and voices, not from speakers. A singer would generally be in front of you (center stage), and the band would be arranged around them. See also "staging."
Submitted on Wednesday, November 08, 2006 1:45:22 PM

5. Imaging-When two or more channels are reproduced in such a manner that our brains are tricked into hearing something that does not really exist. A phantom center is created when identical mono information is reproduced in two identical loudspeakers with a listener seated in between and in front of the two speakers. (e.g., Until Ronnie installed his speakers in pods on the floor, his system didn't image at all.)
Submitted on Thursday, June 29, 2006 1:45:22 PM

6. Imaging
Definition:When two or more channels are reproduced in such a manner that our brains are tricked into hearing something that does not really exist. A phantom center is created when identical mono information is reproduced in two identical loudspeakers with a listener seated in between and in front of the two speakers. (e.g., Until Ronnie installed his speakers in pods on the floor, his system didn't image at all.)
Submitted on Wednesday, October 19, 2005 1:45:22 PM

7. Impedance
Definition:The totality measured in Ohms of all electrical opposition to current flow
Submitted on Friday, July 07, 2006 1:45:22 PM

8. Impedance-Resistance to the flow of alternating current. (e.g., The resistance of a speaker's voice coil may be measured at 3.1 ohms, but the impedance of that speaker may be 10 ohms at 50 Hz.)
Submitted on Friday, August 12, 2005 1:45:22 PM

9. Impedance-Impedance is a measure of electrical resistance specified in ohms. Speakers are commonly listed as 4 or 8 ohms but speakers are reactive devices and a nominal 8 ohm speaker might measure from below 4 ohms to 60 or more ohms over its frequency range. This varying impedance curve is different for each speaker model and makes it impossible to design a really effective "generic" speaker level high-pass filter. Active devices like amplifiers typically have an input impedance between about 10,000-100,000 ohms and the impedance is the same regardless of frequency.
Submitted on Monday, May 23, 2005 1:45:22 PM

10. Impedance:
Resistance to the flow of alternating current. (e.g., The resistance of a speaker's voice coil may be measured at 3.1 ohms, but the impedance of that speaker may be 10 ohms at 50 Hz.)
Submitted on Tuesday, July 26, 2005 1:45:22 PM

11. Inductance (L)-The capability of a coil to store energy in a magnetic field surrounding it. It produces an impedance to an ac current. Inductors are commonly used in audio as low pass crossovers.
Submitted on Friday, February 23, 2007 1:45:22 PM

12. Inductive Coupling:
Radiated noise that is transmitted through a magnetic field to surrounding lines. This frequently occurs in long runs owire where power and signal cables are in too close proximity. This is a frequent source of noise and interference.
Submitted on Sunday, May 21, 2006 1:45:22 PM

13. Inductor:A transformer, or an electrical component in which impedance increases as the frequency of the AC decreases. Also known as coils. In audio, these are used in passive crossovers. Inductors are rated in Henrys.
Submitted on Thursday, January 11, 2007 1:45:22 PM

14. Inductor-Usually a coil of wire that may or may not be placed in a magnetic field. It stores energy in the magnetic field and can be used to alter AC signals. (e.g., We used an inductor as a woofer coil.)
Submitted on Sunday, May 01, 2005 1:45:22 PM

15. Inductor:-Usually a coil of wire that may or may not be placed in a magnetic field. It stores energy in the magnetic field and can be used to alter AC signals. (e.g., We used an inductor as a woofer coil.)
Submitted on Friday, January 14, 2005 1:45:22 PM

16. Infinite Baffle:
An infinite baffle speaker design is defined as an enclosure that contains a greater volume of air than the Vas requirement of the driver. An infinite baffle system can easily be applied to an automobile. This is accomplished by mounting the speakers on a board and using the trunk of the vehicle as the other walls of the enclosure. It is important that the enclosure be tightly sealed such that no air moves from the front to the back of the cone. Look for speakers where the Qts is greater than .6, and a Vas figure lower than the volume available, when selecting a woofer for an infinite baffle system.
Submitted on Tuesday, February 22, 2005 1:45:22 PM

17. Infinite Baffle:A baffle that completely isolates the back wave of a driver from the front without a standard enclosure.
Submitted on Monday, December 05, 2005 1:45:22 PM

18. Infrasonic
Definition:Waves or vibrations with frequencies below that of audible sound (20 Hz.).
Submitted on Saturday, February 05, 2005 1:45:22 PM

19. Infrasonic (Subsonic) Filter-A filter designed to remove extremely low frequency (25Hz or lower) noise from the audio signal. Useful for Ported box designs.
Submitted on Friday, September 02, 2005 1:45:22 PM

20. Input Overload Distortion
Distortion caused by too great an input signal being sent to an amplifier or preamplifier. It is not affected by volume control settings and often occurs when mics are positioned too close to the sound source. This distortion may be controllable through the use of an attenuator or pad.
Submitted on Thursday, December 01, 2005 1:45:22 PM

21. Input Sensitivity-is the SPL (sound pressure level) a speaker will produce given one watt of power as measured from one meter away given a typical input frequency (usually 1kHz unless otherwise noted on the speaker). Typical sensitivities for car audio speakers are around 90dB/Wm. Some subwoofers and piezo horns claim over 100dB/Wm. However, some manufacturers do not use true 1W tests, especially on low impedance subwoofers. Rather, they use a constant voltage test which produces more impressive sensitivity ratings.
Submitted on Friday, July 22, 2005 1:45:22 PM

22. Input Voltage:
The power voltage provided to an amplifier. While most cars can be expect to reliably produce 12 volts, amplifiers are sometimes measured at higher voltages; up to 15 volts. In this way, higher power can be developed, albeit at the expense of longevity. It is a practice that allows higher power figures to be claimed.
Submitted on Thursday, November 11, 2004 1:45:22 PM

23. Insertion Loss
Definition:The loss of voltage (or power), as measured in dB, resulting from placing a resistor (or some other power absorbing network or component) between a voltage or power source (amp) and its load impedance (speaker.) It is the ratio of the voltage (or power) absorbed in the load without the resistor (or network) to that when the network is inserted. For example, if the voltage across a load is 2 volts without a network and 1 volt with the network, then the insertion loss is stated as 6 dB.
Submitted on Saturday, July 30, 2005 1:45:22 PM

24. Insulation or insulator
A non-conductive protective covering for electrically active parts and wire that prevents short circuits and other unwanted interference.
Submitted on Saturday, September 09, 2006 1:45:22 PM

25. Interconnects
Cables that are used to connect components at a low signal level. Examples include CD player to receiver, pre-amplifier to amplifier, etc. Most interconnects use a shielded construction to prevent interference. Most audio interconnects use RCA connections although balanced interconnects use XLR connections.
Submitted on Monday, March 12, 2007 1:45:22 PM

26. Interface-A device or protocol which facilitates the linking of any two devices or systems; or when used as a verb ('to interface'), the process of linking.
Submitted on Wednesday, May 16, 2007 1:45:22 PM

27. Intermodulation Distortion-A species of Distortion that results when one set of frequencies is superimposed on, or is modified by, another to produce a third frequency not present in the original signal. Quantifies the distortion products of nonlinearities in the unit under test that causes complex waves to produce beat frequencies, i.e., sum and difference products not harmonically related to the fundamentals.
Submitted on Saturday, March 18, 2006 1:45:22 PM

28. Inverse Square Law:
In mathematics, the law that states that in the absence of reflective surfaces, sound pressure (or light) falls off at a rate inverse to the square of the distance from its source. In other words, every time the distance from the sound source is doubled, the sound pressure level is reduced by a factor of 4, or 12 dB.
Submitted on Monday, June 13, 2005 1:45:22 PM

29. Isobarik:Sometimes spelled Isobaric, this is an enclosure design in which two or more Drivers are coupled together by a sealed air mass to operate as a single driver. With proper sealing and design, very impressive results can be obtained from an unusually small box. A popular version of this simply consists of two woofers placed over each other in a 'clamshell' design. The downside consists of the fact that it does require at least twice the amplifier power as would be needed for a conventional speaker, in order to be operated successfully.
Submitted on Friday, February 03, 2006 1:45:22 PM

30. Isobarik Enclosure
A trade name for a compound enclosure.
Submitted on Monday, February 19, 2007 1:45:22 PM

31. ISO-DIN Mounting:-Refers to a receiver mounting system in which the headunit is mounted behind the dash panel with side brackets, employing factory installed trim panels.1
Submitted on Saturday, November 04, 2006 1:45:22 PM

32. Isolation:
A term that describes the impedance between the power supply and the signal path of component. It is an indication of power supply noise immunity. (e.g., I know that my equalizer has poor isolation because I never experienced any alternator whine until I installed my EQ.)
Submitted on Wednesday, March 22, 2006 1:45:22 PM

33. Isolation:A term that describes the impedance between the power supply and the signal path of component. It is an indication of power supply noise immunity. (e.g., I know that my equalizer has poor isolation because I never experienced any alternator whine until I installed my EQ.)
Submitted on Tuesday, December 28, 2004 1:45:22 PM

34. Isolation
Definition:Electrical or acoustical separation to prevent the spread of noise and the effect on the signal of unwanted elements produced by internal or external devices.
Submitted on Sunday, November 26, 2006 1:45:22 PM

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