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1. Haas effect
If sounds arrive from several sources, the ears and brain will identify only the nearest. In other words, if our ears receive similar sounds coming from various sources, the brain will latch onto the sound that arrives first. If the time difference is up to 50 milliseconds, the early arrival sound can dominate the later arrival sound, even if the later arrival is as much as 10 dB louder. The discovery of this effect is attributed to Halmut Haas in 1949.
Submitted on Thursday, January 10, 2008 8:46:26 PM

2. Haas Effect
Definition:Also known as precedence effect, describes the human psychoacoustic phenomena of correctly identifying the direction of a sound source heard in both ears but arriving at different times. Due to the head's geometry (two ears spaced apart, sometimes separated by a barrier) the direct sound from any source first enters the ear closest to the source, then the ear farthest away. The Haas Effect describes how humans localize a sound source based upon the first arriving sound, if the subsequent arrivals are between 25-35 milliseconds. If the later arrivals are longer than this, then two distinct sounds are heard. The Haas Effect applies even when the second arrival is louder than the first (even by levels as great as 10 dB.)
Submitted on Monday, December 07, 2009 8:46:26 PM

3. Hard Dome (Tweeter):A characteristic of some Dome tweeters in which the dome is made of some light, hard metal such as neodymium, titanium, or some of the more rigid plastic compounds. The differences in reproduction between hard and soft dome tweeters, are distinctive, but very subtle. Pay close attention to how these sound before purchase.
Submitted on Monday, July 05, 2010 8:46:26 PM

4. Harmonic Distortion:-A type of Distortion in which resonance or sympathetic ringing vibrations are added to the original sound to produce second and third harmonics of a fundamental tone in a way that was not present in the original signal. Choosing good Drivers and a well-made enclosure design is essential in overcoming this tendency in speakers.
Submitted on Sunday, January 06, 2008 8:46:26 PM

5. Harmonics
Also called overtones, these are vibrations at frequencies that are multiples of the fundamental. Harmonics extend without limit beyond the audible range. They are characterized as even-order and odd-order harmonics. A second-order harmonic is two times the frequency of the fundamental; a third order is three times the fundamental; a fourth order is four times the fundamental; and so forth. Each even-order harmonic
Submitted on Sunday, May 23, 2010 8:46:26 PM

6. Harness:
The universal name for a bundle or loom of wires that compose the wiring for a system.
Submitted on Sunday, September 13, 2009 8:46:26 PM

7. Hatchback (box or enclosure):-An enclosure of such size and shape as to enable its efficient use in hatchback-style vehicles. Normally, these enclosures are somewhat deeper than standard angled enclosures and have either handles on the end panels or no handles at all.
Submitted on Monday, May 31, 2010 8:46:26 PM

8. HDCD:High-Definition Compact Disc. A proprietary system by Pacific Microsonics that requires special encoding during the recording process. Some observers report HDCD discs as having better sound. To gain the benefits requires having special HDCD in your CD player.
Submitted on Monday, July 06, 2009 8:46:26 PM

9. Head Amplifier:An active device designed to increase the signal level at the output of the deck. (e.g., We used a head amp to raise the 2.0-volt signal level of my deck up to 6 volts.)
Submitted on Thursday, April 16, 2009 8:46:26 PM

10. Head Amplifier-An active device designed to increase the signal level at the output of the deck. (e.g., We used a head amp to raise the 2.0-volt signal level of my deck up to 6 volts.)
Submitted on Friday, June 19, 2009 8:46:26 PM

11. Head Unit
The in dash control center of a car audio system, usually consisting of an internal low powered amp, AM/FM receiver, and either a tape or CD player (or both).
Submitted on Tuesday, April 22, 2008 8:46:26 PM

12. Headroom:A term related to the dynamic range of amplifiers, used to express in dB, the level between the typical operating level and the maximum output level (onset of clipping). For example, a nominal +5 dBu system that clips at +25 dBu has 20 dB of headroom. Because the term depicts a pure ratio, there are no units or reference-level associated with headroom, only relative "dB." Therefore headroom expressed in dB accurately refers to both voltage and power. Which means the example above has both 20 dB of voltage headroom, and 20 dB of power headroom.
Submitted on Thursday, April 15, 2010 8:46:26 PM

13. Headroom
Definition:The ability of an amp to go beyond its rated power for short durations in order to reproduce musical peaks without distortion. This capability is often dependent on the power supply used in the design.
Submitted on Monday, March 10, 2008 8:46:26 PM

14. Hearing Sensitivity
The human ear is less sensitive at low frequencies than in the midrange. Turn your volume knob down and notice how the bass seems to"disappear". To hear low bass requires an adequate SPL level. To hear 25Hz requires a much higher SPL level than to hear 250Hz. In the REAL world, low frequency sounds are reproduced by large objects; bass drums, string bass, concert grand pianos, etc. Listen to the exhaust rumble of a 454 cubic inch V8 engine vs. the whine of the little four banger. The growl of a lion vs. the meow of your favorite kitty. As frequency decreases we perceive more by feel than actual hearing and we lose our ability to hear exact pitch.
Submitted on Thursday, March 26, 2009 8:46:26 PM

15. Heat Dissipation:
The function of transfering heat away from a component into the air to prevent damage to the output section of an amplifier or the voice coil of a speaker.
Submitted on Tuesday, December 09, 2008 8:46:26 PM

16. Heat Sink-Parts of an amplifier, typically heavy metal "fins," and a section of the frame of the speaker used to conduct and radiate heat away from the ponit of electrical consumption, or motor assembly.
Submitted on Friday, January 16, 2009 8:46:26 PM

17. Hertz
The measurement of frequency. One hertz is equal to one cycle per second, or the complete cycle of an alternating (AC) waveform. Higher frequencies are measured in kilohertz, (thousands of cycles per second) Megahertz, (millions of cycles per second), etc.
Submitted on Thursday, October 29, 2009 8:46:26 PM

18. Hertz (Hz):
A unit of measurement denoting frequency, originally measured as Cycles Per Second, (CPS)
Submitted on Tuesday, December 30, 2008 8:46:26 PM

19. High Fidelity:A method of sound reproduction that emphasizes the highest possible adherence to the exact character of the original sound. This is a principal that must be paramount in every stage of the recording, transportation, and re-creation of the signal to be fully operational. It is usually the listener's equipment wherein this objective is most seriously compromised.
Submitted on Tuesday, July 28, 2009 8:46:26 PM

20. High Level Input:-An audio input configured to accept speaker level signals.
Submitted on Sunday, October 25, 2009 8:46:26 PM

21. High pass
A filter that permits the highs to go through, but attenuates the lows. (e.g., We used a high pass filter on my factory 4-inch dash speakers so that they wouldn't burn up when the bass hits hard.)
Submitted on Monday, June 15, 2009 8:46:26 PM

22. High pass-A filter that permits the highs to go through, but attenuates the lows. (e.g., We used a high pass filter on my factory 4-inch dash speakers so that they wouldn't burn up when the bass hits hard.)
Submitted on Monday, October 06, 2008 8:46:26 PM

23. High Pass Filter:
An electronic filter of a type commonly incorporated in Crossover circuits that permits the passage of high frequencies while suppressing lower ones. The place in the frequency spectrum where this occurs is called the crossover point and is different for each set of Drivers being considered. The most basic form of such filter is a non-polarized capacitor. Typical values for such a unit would be in the range of 1 to 100 microfarads.
Submitted on Tuesday, June 23, 2009 8:46:26 PM

24. High Power Output
Definition:Speaker level outputs driven by an amplifier, typically at least 15 watts RMS per channel.
Submitted on Tuesday, August 03, 2010 8:46:26 PM

25. High Voltage Switching Power Supply
Definition:An amplifier's internal power supply that converts the vehicle's 12 volts to higher voltage for improved dynamic range and higher amp output power.
Submitted on Friday, May 09, 2008 8:46:26 PM

26. High-Pass Filter
A circuit that allows high frequencies to pass but rolls off the low frequencies. When adding a subwoofer it is often desirable to roll-off the low frequencies to the main amplifiers and speakers. This will allow the main speakers to play louder with less distortion. High-pass filters used at speaker level are usually not very effective unless properly designed for a specific main speaker (see impedance below).
Submitted on Saturday, July 12, 2008 8:46:26 PM

27. Hiss
Audio noise that sounds like air escaping from a tire.
Submitted on Tuesday, February 09, 2010 8:46:26 PM

28. Home Theater:An audio system designed to reproduce the theater sound experience while viewing film at home. Minimally consisting of a Dolby Pro Logic® surround sound receiver, left and right front speakers, a center channel speaker, and two surround speakers. These plus optional subwoofer(s), surround speaker(s), and digital formats such as Dolby Digital® can enhance the viewing experience by drastically improving the sound quality of movie soundtracks.
Submitted on Thursday, May 07, 2009 8:46:26 PM

29. Horn
Definition:A type of speaker system now principally used for high-frequency reproduction, but which is capable of full range sound in its largest format. As with those huge alpine horns, even the smallest transducer or diaphragm can produce the lowest sound if the horn is long enough and large enough at its business end. (see Compression Driver above)
Submitted on Tuesday, December 29, 2009 8:46:26 PM

30. Horn
Definition:A speaker design scheme in which the cross-sectional area is constantly increasing from input to output. (e.g., A compression driver usually uses a horn on its output.)
Submitted on Thursday, April 17, 2008 8:46:26 PM

31. Horn:
A speaker design scheme in which the cross-sectional area is constantly increasing from input to output. (e.g., A compression driver usually uses a horn on its output.)
Submitted on Wednesday, January 02, 2008 8:46:26 PM

32. Horn Tweeter-A driver consisting of a relatively small emitter surmounted by a curvilinear or exponential horn. This is an effective system for radiating high frequencies in a variety of situations. The size and shape of the horn will usually dictate the pattern and use of the driver. Long horns with narrow apertures, tend to have the narrowest radiation pattern, and are very useful in large listening rooms, especially where highly directional effects, such as surround sound requires, are mandatory. Shallower versions have more general applications, especially in car stereo applications where a wider field of coverage is desired, along with a robust driver that can withstand severe environments. In such situations, a Piezo driven emitter (driver) is highly desirable for its ability to handle high-energy inputs on a variable basis. Horns can be driven by a number of different driver types
Submitted on Saturday, February 13, 2010 8:46:26 PM

33. Hum
Audio electronic noise that has a steady low frequency pitch.
Submitted on Friday, November 21, 2008 8:46:26 PM

34. Hum components:
The residual artifact harmonics of the AC power supply. In the U.S. the use a 60-Hz system, places the most annoying 2nd and 3rd harmonics at 120 Hz and 180 Hz. For Europe, and other parts of the world using 50-Hz mains, these components fall at 100 Hz and 150Hz. To some extent, this is present with nearly all non automotive sound systems and is generally accounted as noise.
Submitted on Wednesday, January 23, 2008 8:46:26 PM

35. Hyperbaric Resonator Impulse
Definition:An audible event characterized by a sudden and often unexpected pressure wave emanating from a vent port with a driver whose energetic and propulsive energy transitions, are generated by a process involving the chemical modification of legumes. This phenomenon frequently produces olfactory irritation in associated groups in consequence. This event is also know as a Farsical Audio Report Transient.
Submitted on Wednesday, August 25, 2010 8:46:26 PM

36. Hypercardioid-A narrower heart-shaped pick-up pattern than that of cardioid microphones.
Submitted on Monday, November 17, 2008 8:46:26 PM

37. Hz (short for Hertz):-The term that stands for events or cycles per second. 1 kHz=1000 Hz, 1 MHz=1,000,000 Hz, 1 GHz=1,000,000,000 Hz. (e.g., A frequency of 50 Hz means that something is repeating 50 times per second.)
Submitted on Tuesday, July 13, 2010 8:46:26 PM

38. Hz (short for Hertz):The term that stands for events or cycles per second. 1 kHz=1000 Hz, 1 MHz=1,000,000 Hz, 1 GHz=1,000,000,000 Hz. (e.g., A frequency of 50 Hz means that something is repeating 50 times per second.)
Submitted on Monday, July 26, 2010 8:46:26 PM

39. Hz is for hertz-a measure of frequency. One hertz is equal to "one cycle" per second. A cycle of sound is the duration between similar portions of a sound wave (between two peaks, for instance). Frequency can describe both electrical circuits and sound waves, and sometimes both. For example, if an electrical signal in a speaker circuit is going through one thousand cycles per second (1000Hz, or 1kHz), the speaker will resonate at 1kHz, producing a 1kHz sound wave. Got all that?
Submitted on Wednesday, July 16, 2008 8:46:26 PM

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