P

1. Pad
Definition:An electrical circuit used to attenuate or reduce the amplitude of an audio signal by a fixed amount, e.g a -15dB pad reduces the signal by a fixed 15 decibels.
Submitted on Saturday, August 09, 2008 8:50:59 PM

2. Pan Pot:-Short for panoramic potentiometer, this is a knob controlling a voltage divider that can send a signal to a combination of two busses, such as left and right. Always found on mixing consoles to set up (pan) a signal within the stereo field, it is also called a 'balance' control on domestic stereo amplifiers.
Submitted on Wednesday, July 07, 2010 8:50:59 PM

3. Parallel
A circuit topology that connects multiple circuits to the same connectors. (e.g., We connected four 8 ohm woofers in parallel so that we could really load down our amplifier.)
Submitted on Wednesday, May 07, 2008 8:50:59 PM

4. Parallel:
A circuit topology that connects multiple circuits to the same connectors. (e.g., We connected four 8 ohm woofers in parallel so that we could really load down our amplifier.)
Submitted on Tuesday, August 05, 2008 8:50:59 PM

5. Parallel Wiring
Definition:A circuit in which two or more devices are connected to the same source of voltage, sharing a common positive and negative point, so that each device receives the full applied voltage.
Submitted on Tuesday, March 25, 2008 8:50:59 PM

6. Parametric-A type of equalizer that permits the center frequency, the filter shape, and the amplitude of each band to be varied. (e.g., You should save up for a good parametric equalizer so that you can dump your old 5 band graphic EQ.)
Submitted on Tuesday, April 13, 2010 8:50:59 PM

7. Parametric-A type of equalizer that permits the center frequency, the filter shape, and the amplitude of each band to be varied. (e.g., You should save up for a good parametric equalizer so that you can dump your old 5 band graphic EQ.)
Submitted on Wednesday, April 02, 2008 8:50:59 PM

8. Parametric Equalizer
Definition:A multi-band equalizer enabeling control of at least three essential "parameters" of the internal bandpass filter sections. These parameters being
Submitted on Wednesday, February 03, 2010 8:50:59 PM

9. Passive
Definition:The type of circuitry that does not

require external power, but rather uses only basic circuit elements such as capacitors, inductors, and resistors. (e.g., We used two capacitors and one inductor to make a 6 dB/octave passive crossover for our midrange speakers.)
Submitted on Saturday, November 14, 2009 8:50:59 PM

10. Passive:The type of circuitry that does not

require external power, but rather uses only basic circuit elements such as capacitors, inductors, and resistors. (e.g., We used two capacitors and one inductor to make a 6 dB/octave passive crossover for our midrange speakers.)
Submitted on Sunday, January 17, 2010 8:50:59 PM

11. Passive Component:In a crossover system, a non-powered component used to separate an audio signal into a specified frequency band before it goes to a particular amplifier or driver. A passive device usually incurs some loss (expressed in decibels) to a system. Typical such components include capacitors, coils, and resistors.
Submitted on Wednesday, July 07, 2010 8:50:59 PM

12. Passive Crossover-Uses inductors (coils) and capacitors to direct proper frequencies to appropriate drivers. These crossover systems can be simple (First Order = 1 component @ -6 dB/octave slope) to complex (Fourth Order = 4 components @ -24 dB/octave slope).
Submitted on Friday, October 02, 2009 8:50:59 PM

13. Passive Radiator:Sometimes known as a "drone cone," these passive devices respond to internal pressure within the speaker and react to it to produce reinforcing emissions to extend the output of the lower frequencies below the resonance point of the active woofer. They may look like Drivers but they lack an active motor assembly.
Submitted on Tuesday, May 25, 2010 8:50:59 PM

14. Passive Radiator:A device that looks just like an ordinary driver, except it has no magnet or voice coil. A passive radiator is usually a highly compliant device, with a similar cone material and surround found on regular active drivers. The radiator must usually be at least as large (or larger) than the driver it is aligned with. The passive radiator is tuned to Fb and used in place of a port.
Submitted on Friday, September 12, 2008 8:50:59 PM

15. PCM:-Pulse Code Modulation. A means of digital encoding.
Submitted on Wednesday, May 28, 2008 8:50:59 PM

16. Pe:
Driver's rated RMS power handling capability.
Submitted on Saturday, July 05, 2008 8:50:59 PM

17. Peak:The maximum amplitude of a voltage or current.
Submitted on Saturday, April 18, 2009 8:50:59 PM

18. Peak Power Handling (MAX):-Peak power handling refers to the amount of power a speaker is estimated to handle during a brief high-intensity musical burst. Since this can vary with both frequency and amplitude, it is a much less accurate way to judge speaker durability and performance than RMS (see RMS).
Submitted on Wednesday, June 18, 2008 8:50:59 PM

19. Peak power rating-Another meaningless specification unless references are given..
Submitted on Wednesday, January 14, 2009 8:50:59 PM

20. Peak-to-Peak power rating
Definition:See above.
Submitted on Monday, April 13, 2009 8:50:59 PM

21. Period:The amount of time required to complete a full single cycle of a sound wave.
Submitted on Tuesday, December 02, 2008 8:50:59 PM

22. Permalloy Tape Head:
A cassette tape head constructed of permalloy, an alloy made primarily of nickel and iron, used for its superior high wear resistance and permeability, offering superior frequency response at a low cost.
Submitted on Tuesday, March 25, 2008 8:50:59 PM

23. Phase
Definition:The relative timing of a sound wave that is measured in degrees from 0 to 360.
Submitted on Wednesday, December 10, 2008 8:50:59 PM

24. Phase
The time relationship between two AC (alternating current) signals. (e.g., In an AC circuit the current and voltage may experience a phase shift.)
Submitted on Thursday, January 21, 2010 8:50:59 PM

25. Phase
The time relationship between two AC (alternating current) signals. (e.g., In an AC circuit the current and voltage may experience a phase shift.)
Submitted on Saturday, July 24, 2010 8:50:59 PM

26. Phase Cancellation:Audio signals are complex phenomena expressed mathematically as phasors, or vectors. When two signals have the same exact time relationship to each other, they are said to be "in-phase;" if they do not, they are said to be "out-of-phase." If the energy of two out-of-phase signals are combined, they will, in fact, subtract from one another. This is called phase cancellation. Another type of phase cancellation can be seen when water waves interact. One wave's energy becomes stronger when two waves collide in-phase (summing) and becomes weaker when they collide out-of-phase. Air (barometric) fronts act in the same way.
Submitted on Sunday, December 30, 2007 8:50:59 PM

27. Phase Coherence:The relationship and timing of sounds that come from different drivers (subs, mids, tweets) mounted in different locations.
Submitted on Wednesday, July 29, 2009 8:50:59 PM

28. Phase Delay-A phase-shifted sine wave appears displaced in time from the input waveform. This displacement is called phase delay.
Submitted on Friday, October 24, 2008 8:50:59 PM

29. Phase Distortion
A type of audible distortion caused by time delay between various parts of the signal.
Submitted on Wednesday, June 17, 2009 8:50:59 PM

30. Phase Linear
Any audio system which accurately preserves phase relationships between frequencies, i.e., that exhibits pure delay.
Submitted on Saturday, July 03, 2010 8:50:59 PM

31. Phase Shift:-The fraction of a complete cycle elapsed as measured from a specified reference point and expressed as an angle. 2. Out of phase in an un-synchronized or un-correlated way.
Submitted on Thursday, March 18, 2010 8:50:59 PM

32. Phon:
A unit of apparent loudness, equal in quantum to the intensity in decibels of a 1,000 Hz tone estimated to be as loud as the sound being measured.
Submitted on Sunday, August 02, 2009 8:50:59 PM

33. Piezo (Tweeter):A tweeter whose motor is simply a crystal of Piezo material through which the signal current flows. The crystal lattice responds to this by bending in proportion to the Amplitude and frequency of the incoming signal. Because it is a high impedance device, it does not need a Crossover in line with the source. Piezo tweeters are very efficient Drivers and are relatively inexpensive. They come in a large variety of designs and radiators.
Submitted on Saturday, May 10, 2008 8:50:59 PM

34. Piezoelectric Driver:-This is among the most robust and least expensive alternative drivers for the high frequency reproduction. The material used in the Piezoelectric Driver is a piezoelectric polymer first developed in the early 1960's. This piezoelectric polymer is a plastic-like material that, unlike a crystal, can be made into thin sheets and fashioned into a great variety of shapes. Its transient and high frequency response is very good because the moving mass is negligible. The driver operates by bending the lattices in the crystalline structure of the piezoelectric polymer film. The Piezoelectric Driver is inappropriate for low frequency applications, as it is incapable of large air displacements. This high frequency transducer is very uniform in response from approximately 2 kHz to 20 kHz. It typically is used in many car stereo enclosures and other compact space environments.
Submitted on Thursday, April 08, 2010 8:50:59 PM

35. Pink Noise
Pink noise is a random noise source characterized by a flat amplitude response per octave band of frequency, i.e., it has equal energy, or constant power, per octave. Pink noise is created by passing white noise through a filter having a 3 dB/octave roll-off rate. Due to this roll-off, pink noise sounds less bright and richer in low frequencies than white noise. Since pink noise has the same energy in each 1/3-octave band, it is the preferred sound source for many acoustical measurements in respect to the critical band concept of human hearing. The name comes from the filtering of white noise. White noise is analogous to white light in that it contains all audible frequencies distributed uniformly throughout the spectrum. Passing white light through a prism (a form of filter) breaks it down into a range of colors. Examination shows that red light is characterized by the longer wavelengths of light, i.e., light in the lower frequency region. Similarly, pink noise has higher energy in the low frequencies, hence the term, pink.
Submitted on Thursday, February 11, 2010 8:50:59 PM

36. Pitch:-The subjective sensation produced by various frequencies. The higher the frequency, the higher the perceived pitch; however, frequency is not linearly related to pitch. See also 'Concert Pitch'.
Submitted on Tuesday, May 06, 2008 8:50:59 PM

37. Planar Source
Most electrostatics and magnetic planars have a large surface area. Think of a wide board dropped flat onto the water surface. The sound can be extremely coherent, but the listening window is effectively limited to being directly on-axis of both the left and right planar speaker.
Submitted on Wednesday, December 30, 2009 8:50:59 PM

38. Point-Source:
Most multi-unit loudspeakers try to approximate a point-source. Think of a pebble dropped into the water and the expanding wave pattern away from impact. Obviously it is difficult to integrate multiple point-sources into a truly coherent expanding wave. The best designs do quite well with careful driver engineering and crossover development.
Submitted on Tuesday, January 12, 2010 8:50:59 PM

39. Polar response:
A plot of the Amplitude measurement of a speaker's output at a given frequency relative to an off-axis angle. In other words, the difference that exists between how a speaker sounds when being heard directly in front, compared to how it sounds while standing off to one side. (See Dispersion)
Submitted on Thursday, January 03, 2008 8:50:59 PM

40. Polarity
The direction or polarization of a signal entering or leaving a component. For instance, if a positive signal is applied to the input of a device, and that device emits a positive signal, then it is said to be a non-inverting device. Polarity merely describes a direction and should not be confused with phase. (e.g., It is important to maintain similar polarity throughout an entire speaker system so that all the speakers will be working together.)
Submitted on Thursday, February 12, 2009 8:50:59 PM

41. Polarity
A speaker, for example, has a positive and a negative input terminal. Connecting a battery directly to the speaker will result in the diaphragm moving outward. If you reverse the battery leads, the diaphragm will move inward. Caution
Submitted on Sunday, August 16, 2009 8:50:59 PM

42. Polarity:The direction or polarization of a signal entering or leaving a component. For instance, if a positive signal is applied to the input of a device, and that device emits a positive signal, then it is said to be a non-inverting device. Polarity merely describes a direction and should not be confused with phase. (e.g., It is important to maintain similar polarity throughout an entire speaker system so that all the speakers will be working together.)
Submitted on Monday, October 19, 2009 8:50:59 PM

43. Pole Piece:The ends or "Poles" of a magnet from which the magnetic lines of force, measured in Gauss, are at the greatest strength. In a typical speaker, this will be at the gap within which the voice coil is located. (see Bumped & Vented)
Submitted on Thursday, August 21, 2008 8:50:59 PM

44. Polycarbonate
A polymer based plastic material offering superior resistance against resonance.
Submitted on Saturday, August 14, 2010 8:50:59 PM

45. Polypropylene
Definition:A plastic based material used primarily for speaker cones due to its rigidity, damping and resistance against harsh environmental conditions.
Submitted on Thursday, July 10, 2008 8:50:59 PM

46. Port
An opening, usually a tube, in an enclosure, through which sound is permitted to pass.
Submitted on Saturday, July 25, 2009 8:50:59 PM

47. Port Diameter:-The measurement across the port opening. Measured as internal diameter (not outer diameter .
Submitted on Thursday, April 09, 2009 8:50:59 PM

48. Port Length:
The measurement of the length of the port tube.
Submitted on Monday, August 25, 2008 8:50:59 PM

49. Ported
Definition:A type of bass reflex enclosure design that utilizes a hole, or port, to improve the low-frequency response. (e.g., In most cases a ported enclosure will thump harder than a sealed box, but not over as wide a range of frequencies.)
Submitted on Sunday, February 28, 2010 8:50:59 PM

50. Ported:-A type of bass reflex enclosure design that utilizes a hole, or port, to improve the low-frequency response. (e.g., In most cases a ported enclosure will thump harder than a sealed box, but not over as wide a range of frequencies.)
Submitted on Friday, May 01, 2009 8:50:59 PM

51. Ported (enclosure)
Any enclosure design with ports. In such designs the internal pressure wave is processed to be used either solely, or in conjunction with the woofer front wave in order to produce sound. A port can be a simple opening, a tube or a Passive Radiator.
Submitted on Friday, March 06, 2009 8:50:59 PM

52. Ported Enclosure:
A type of speaker enclosure that uses a duct or port to improve efficiency at low frequencies.
Submitted on Wednesday, February 24, 2010 8:50:59 PM

53. Potentiometer
Definition:A three-terminal variable resistor. Two terminals connect to the ends of a flat resistor, while the third terminal is attached to a moveable contact that interfaces with the resistive element. The moveable terminal, or slider, is capable of being positioned from one end of the element to the other. There are many physical types, with the rotary design being the most common, followed by linear slider used in graphic equalizers, for example. Often used as voltage dividers in electronic circuits, the input voltage is applied to the top of the resistive element, while the other end is tied to ground or a common reference and the output is taken from the slider. When the slider is positioned to the top extreme, the output equals the input less of course, the effect of the resistor, moving it to the bottom extreme gives an output of zero volts; and every possible level between is available as the slider is moved from one end to the other. The most commonly encountered application of this arrangement to control the volume of an audio device. In this way the electrical potential is varied, hence, a potentionmeter. The rate at which the voltage changes as the slider is moved is controlled by the taper of the pot. The taper defines the amount of resistive change as a function of travel. Several popular examples are listed below
Submitted on Thursday, January 22, 2009 8:50:59 PM

54. Power-a. The product of applied voltage (potential difference) and current in a direct-current circuit (or the voltage squared divided by the resistance, or the current squared times the resistance). b. The product of the effective values of the voltage and current with the cosine of the phase angle (between current and voltage) in an alternating-current circuit. c.Power The amount of energy (in joules) that a device delivers or consumes divided by the time (in seconds) that the device is operating. See
Submitted on Wednesday, February 04, 2009 8:50:59 PM

55. Power (P):
The time rate of doing work or the rate at which energy is used. One equation for Power
Submitted on Friday, October 23, 2009 8:50:59 PM

56. Power amplifier-The final stage of amplification. (e.g., You must use a power amplifier to drive your speakers.)
Submitted on Friday, November 28, 2008 8:50:59 PM

57. Power amplifier:
The final stage of amplification. (e.g., You must use a power amplifier to drive your speakers.)
Submitted on Sunday, May 31, 2009 8:50:59 PM

58. Power factor
Definition:The ratio of the total power in watts (resistive load) to the total apparent power in voltamperes (VA) (reactive load). The difference between watts and VA is due to reactive load impedance. Apparent power equals watts only for a purely resistive load (i.e., zero degrees phase shift between the applied voltage and the resultant current). Power factor is best thought of intuitively as the multiplier (ranging between 0 and 1) that you must use to obtain the real power from the apparent power. For example if the rms voltage and current of a circuit is measured and multiplied together, the apparent power is obtained, but this value must be multiplied by the power factor to obtain the real power. If the load is purely resistive then the phase difference between the voltage and current will be zero and the power factor will be one, and the apparent power will equal the true power -- but only for a resistive load. For a reactive load (any load with inductive and/or capacitive reactance, i.e., any real world load) there will be a phase difference between the voltage and the current due to the phase delay introduced by the reactive elements. Simply put, since the maximum voltage and current do not occur at the same instant of time the amount of power developed is less than the measured rms voltage and current multiplied together.
Submitted on Tuesday, August 04, 2009 8:50:59 PM

59. Power Handling (continuous or RMS):-A rating of a Driver's ability in optimum conditions to handle a specified amount of audio power (electrical current power) on a constant basis, without damage. This is generally considered to be a conservative and reliable figure to use in judging what types of amplifier power will be most successful with a particular speaker design.
Submitted on Friday, June 06, 2008 8:50:59 PM

60. Pre-Amp
Definition:A circuit unit which takes a small signal and amplifies it sufficiently to be fed into the power amplifier for further amplification. A pre-amp includes all of the controls for regulating tone, volume, and channel balance.2
Submitted on Sunday, May 30, 2010 8:50:59 PM

61. Preamp Output:
Typically found on headunits, a preamp output provides low level, high quality audio signal for use with external amplifiers.
Submitted on Thursday, April 24, 2008 8:50:59 PM

62. Preamplifier-The first stage of amplification in which the amplitude of a very low-level audio signal is increased. (e.g., Most car audio decks have four separate preamplifier outputs that correspond to the Front Left, Front Right, Rear Left, and Rear Right channel outputs.)
Submitted on Sunday, May 10, 2009 8:50:59 PM

63. Preamplifier
The first stage of amplification in which the amplitude of a very low-level audio signal is increased. (e.g., Most car audio decks have four separate preamplifier outputs that correspond to the Front Left, Front Right, Rear Left, and Rear Right channel outputs.)
Submitted on Friday, January 23, 2009 8:50:59 PM

64. Pre-amplifier
Definition:Or Pre-amp is a device that takes a source signal, such as from a turntable, tape-deck or CD player, and passes this signal on to a power-amplifier(s). The pre-amp may have a number of controls such as source selector switches, balance, volume and possibly tone-controls.
Submitted on Tuesday, June 10, 2008 8:50:59 PM

65. Precedence Effect:
Also known as the Haas effect, this phenomenon identifies the tendency for the ear to attribute all perceived sound to the nearest emitter, even if a more distant speaker is actually louder. Thus, drums that yield 90 percent or more of their energy in the non-directional lower frequencies are perceived as located in the space created by the tiny amount of higher frequency overtones. It is also for this reason that sounds from the rear speakers of a surround system are delayed by 10 to 30 milliseconds, so that they can be experienced as coming from the rear direction.
Submitted on Monday, December 14, 2009 8:50:59 PM

66. Preset:A collection of system settings stored in a memory that is virtually instantly recallable, typically at the touch of a button.
Submitted on Saturday, February 14, 2009 8:50:59 PM

67. Program Bank:
A Custom File feature that allows the user to flag the tracks on a disc, indicating whether they should be played or skipped.
Submitted on Friday, December 19, 2008 8:50:59 PM

68. Program Play-A Custom File feature that allows the user to define a sequence of 12 tracks, in a specific order, for customized playback. Up to two banks of 12 track sequences can be recalled, for up to 24 tracks total.
Submitted on Thursday, December 10, 2009 8:50:59 PM

69. Proximity Effect-An increase in the bass response of some microphones as the distance between the mike and its sound source is decreased.
Submitted on Friday, November 07, 2008 8:50:59 PM

70. Psychoacoustics
Definition:The scientific study of the relationship between human hearing and its stimulus; in other words, how we hear.
Submitted on Thursday, February 28, 2008 8:50:59 PM

71. Punch:Like "hitting hard," a subjective colloquial term that describes the snap or deep impact of the low end response of an audio system
Submitted on Saturday, August 08, 2009 8:50:59 PM

72. Push-pull:-Most common type of amplification that amplifies the negative and positive sides of the waveform separately. Allows for much higher power output than single-ended.
Submitted on Friday, February 26, 2010 8:50:59 PM

73. Push-Pull Configuration:-One driver is mounted normally, the second is mounted so that it faces into the enclosure, both sharing the same internal volume and wired out of phase with one another. Although electrically out of phase with one another, the drivers are acoustically in phase since they move in the same direction. This alignment theoretically reduces second order harmonic distortion.
Submitted on Monday, December 07, 2009 8:50:59 PM

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