A-B
Test
A test
of some aspect of performance between two components. For example, a test of ambient
noise between two different amplifiers can be compared. For the test to be scientifically
valid, the input levels should be matched.
ABX Comparator
A device
that randomly selects between two components for subjective testing. The listener
doesn't know which device
is being listened to. A high consistency of responses is regarded as significant.
AC
Acronym for Alternating Current. An electrical current that reverses direction,
alternating between positive and negative at a constant frequency- in the US,
60 hertz or cycles per second. The rate of change is measured in cycles per second,
or hertz (hz). The majority of consumer electronics products --although they plug
into the wall and receive alternating current--operate in a direct current environment,
necessitating the inclusion of a transformer power supply to perform AC to DC
conversion.
AC-3
Acronym for Audio Codec-3. "Perceptual Coding"
data reduction system developed by Dolby Laboratories to deliver 6 discrete audio
channels ( Left, Center, Right, Left Surround, Right Surround, and Low Frequency
Effects) in a theater environment. See, Dolby Digital Surround Sound.
Active
Crossover
An electronic circuit that divides a line level audio signal
into two or more frequency bandwidths and routes each to their appropriate amplifier.
Active or Powered Subwoofer
A subwoofer system that includes a built
in amplifier(s)
A-D Convertor
Electronic circuit that converts
an analog audio signal which varies in amplitude, into a digital signal, read
as a numeric code created by series of pulses.
AM
Acronym for
Amplitude Modulation, a process that modifys the amplitude of a carrier wave in
accordance with variations to the input voltage of the signal. This form of transmission
is used in radio broadcast bands between 530 and 1750 kilohertz. Because it is
subject to noise, interference, and restricted frequency response, it is not considered
a high fidelity medium.
Ambience
The acoustic characteristics of
a space with regard to reverberation or sound reflection. A room with a lot of
reverb is said to be "live"; one without much reverb is "dead."
.
Amplitude
Measurement of the strength of a signal. Usually measured
in volts or decibels.
Analog
A signal that varies in amplitude,
and is not characterized by discrete pulses (digital). A representation of original
wavwefroms. It is a form of transmission, that in audio, represents in electrical
terms, an acoustical waveform.
Audible Spectrum
It is generally
accepted that humans on average can hear audio frequencies varying from 20hz to
20,000hz. As we age the sensitivity to higher frequencies in the scale of our
audible range progressively declines after about age 18. Attendance at rock concerts
and other high decibel environments will acclerate the process.
Audiophile
A
person who enjoys reading obscure information like this.
Attenuation
A process that reduces the amplitude or gain of an input signal.
Baffle
Sometimes used to describe a speaker cabinet, a baffle increases low frequency
response of a speaker by providing an acoustical seal to prevent air being pushed
out by the front of the speaker from interacting with air of similar amplitude
and frequency, but 180 degreees out of phase behind the speaker. This prevents
cancellation.
Band Pass Filter
A circuit that permits a limited
range (or band) of frequencies to pass through unattenuated
Bandwidth
The gradient, or difference between the highest and lowest frequencies being transmitted.
A higher bandwidth permits more information to be included, or transmitted in
the signal. See, "Full bandwidth"below.
Basket
The frame
or metal portion of a speaker driver that supports the magnet and cone suspension
system.
Bass Reflex
A speaker system that utilizes a port in its
enclosure and regulates the emmision of rear pressure so as to support rather
than conflict, with the front wave. This enhances low frequency response.
Bi-amplify
The use of multiple amplifiers, feeding different parts
of a speaker system, as in separately amplified woofers, and midrange/tweeters.
Could be built into the speaker design or accomplished with the use of external
amplifiers and electronic crossovers.
Bias
A high frequency signal
used with tape media to elevate its frequency response by energizing the magnetic
media..
A term applied to the electrical, mechanical or magnetic force or
voltage applied to a device to establish the reference for nominal operation.
Binary Code
Information that is presented as a numeric bitstream
of ones and zero's. The language of digital media.
Bipolar
A speaker
that radiates signals from the front and the back of the enclosure. Both signals
are in phase to each other. Bi-polar speaker designs are sometimes utilized to
create a diffuse rear channel in a Pro-Logic surround environment.
Bridging
The process of combining two channels of a stereo amplifier to create a more powerful
mono amplifier. This process involves changes in the electrical circuitry that
divide a single input into positive and negative sections and amplifies each separately.
It then recombiners them at the terminus of the process. This modification is
unique to each amplifier, and should not be attempted without the manufacturer's
instructions. Often used in car stereo applications. The output will often be
at high impedance only. An option found less frequently in pro and consumer applications.
Bright
Listening term. Usually refers to overly intense high frequency
energy
Center Channel Speaker
The key component in a Pro-Logic or Dolby Digital Surround audio system. Key to
reproducing dialogue, the output of a center channel speaker can constitute more
than 60% of what is heard in a home theater system.
Clipping
The
chopping off of the peaks of analogue waveforms (plateau-ing, if you will) that
occurs when a signal has more amplitude than a process can pass on. The amplifier
then cuts off the tops and bottoms of the waveforms, producing in effect alternating
DC instead of AC. Excess clipping can easily damage speaker drivers in an audio
system.
Coaxial
Phrase utilized to designate a speaker or speaker
enclosure that features two drivers aligned along the same axis.
A phrase
use to describe an speaker system that by its design, construction elements, or
component selection expands the balance of musical tones. Also refers to cables
where a signal carrier is protected by an outer ground.
Coherence
Listening term. Refers to how well integrated the phase and crossover response
of the system is realized.
Coloration
Listening
term. A visual analog. A "colored" sound characteristic adds something
not in the original sound. The coloration may or may not be euphonically pleasant,
but it is not as accurate as the original signal.
Compression Loaded
A cabinet enclosure that incorporates two woofers acting in tandem or mounted
facing each other, facing away from each other, or even facing behind another.
Cone
A
transducer (speaker) design that efficiently communicates radiated sound to a
listening area. Sound is more restricted in coverage as frequency rises, so use
in woofers and midranges is preferred.
Crossover
An electronic
(and sometimes passive) circuit that divides frequencies and routes them to their
appropriate amplifiers (electronic crossover ) or speakers (passive crossover)
Crosstalk
Undesirable leakage signal from one channel to another usually
resulting in interference, or noise in the signal.
DAC
Acronym for digital to analog convertor. Converts binary pulse information into
audible analog signals that vary in amplitude. Commonly used in many kinds of
digital media - CD's DVD's, digital satellite and cable transmissions.
Damping
The physical process of controlling resonance; or how well an amplifier controls
speaker cone resonance after a signal is reproduced. Speakers may be electronically
or physically dampened. Works by applying a countervailing signal to prevent the
cone from moving after a hgh level signal is applied.
db - Decibel
Acronym for decibel, a logarithmic measure of sound. For every 3 decibels of audio
gain, (the average sound differential a human can perceive) the wattage of an
amplifier is doubled. An increase of 10 db is perceived as being twice as loud.
DC
Direct Current: An electrical current that flows in one direction.
Dipolar
A speaker that radiates signals from the front and
the back. Both signals are out of phase to the other. A Di-polar design is often
utilized to enhance dispersion and create additional ambients in the signal.
Dolby Digital Surround Sound
Selected as the main audio system for
DVD and Advanced Television, Dolby Digital Surround Sound is a data reduction
process utilizing "perceptual coding" to compress up to 6 discrete streams
of audio information into a data rate of 384 kilobits per second in the Theater
environment or 448 kilobits per second in consumer applications (DVD/ATV). Perceptual
Coding operates on the premise of reducing redundant data during the encoding
process, masking noise and eliminating non-perceptual elements of the audio signal
entirely.
Dolby Digital Surround is characterized by 5 full frequency (20
to 20khz) discrete channels ((Left, Center, Right, Left Surround, Right Surround))
of information. A discrete center channel localizes all dialogue entirely in this
speaker with no bleed over in Left, Right or Surround channels. The discrete nature
of all 5 channels allows audio images to be panned across the front, across the
back, along each side, diagonally and full circle. Further, because the center
channel is full range, music and sound effects may be panned across the front
soundstage without frequency deviation as the image passes from Left to Center
and Right.
An additional low bandwidth channel of information in the datastream
(the .1 in the 5.1) is dedicated entirely by the Foley artists to reproducing
Low Frequency Effects (20 to 120hz) which add a greater dynamic to the audio experience.
Dolby Pro-Logic Surround Sound
Four channel surround sound process
(Left/Center/Right and Surround). These four images are mixed into the Left Total
and Right Total signals during encoding, permitting ProLogic signals to be embedded
in, and ultimately read from a standard Left and Right channel stereo soundtrack.
This process of encoding four channels into two carriers, ( Left and Right ) and
retrieving them as 4 channels on the decode side is referred to as 4-2-4. The
defining element of ProLogic is that it utilizes active decoders to localize dominant
audio tracks (to position them correctly within the 360 degree sound stage in
accordance to their proper established amplitudes) through the use of a high separation
decoder processing. Frequency response of the rear channels is limited to 100hz
to 7,000hz to eliminate crosstalk and sibilance errors between the center channel
and rear surround. Low frequency non-directional signals (20-120) are generally
routed to a subwoofer for reproduction.
Rather than measure absolute gain
values to determine soundtrack dominance, Dolby Pro-Logic detects the differences
in levels between signals to establish location and direction of dominant signals.
The advantage of ProLogic is that it continuously monitors the signal to identify
dominant as well as ambient components of the soundtrack. Enhancement and localization
of dominant signals therefore is in proportion to their gain over embedded ambient
tones. In some instance, enhancement will be large and powerful, more often, it
is continuous and subtle.
Dome Tweeter or midrange
A driver that
has a dome shaped radiator. This is very effective with higher frequencies, in
dispersing sound over a wide area, and is very popular. Domes can be of soft or
hard materials to produce slightly different characteristics Other alternatives
are cone and ribbon drivers.
Driver
A synonym for a transducer such
as a woofer, midrange, tweeter, etc.
DSP
Acronym for Digital Signal
Processing. Manipulation of an electronic signal using reverberation or delay
lines and equalization to replicate ambient acoustics of a variety of audio environments.
(Theater, Stadium, Night Club, etc.)
DTS
Positioned as a competitor
to Dolby Digital, DTS audio is delivered in a theatrical environment as 5.1 channel
Compact Disc that is synchronized to the film. In the home environment, DTS utilizes
a compression scheme that insignificantly more bit hungry than its Dolby AC-3
counterpart. (1.2 megabits per second versus 448kbs for Dolby Digital) Proponents
of DTS claim that the higher bit rate provides a smoother, sonically balanced
audio performance. Like AC-3, DTS requires a dedicated processor to decode the
compressed datastrea
Dynamic Headroom
The ability of an audio
device to respond to musical peaks. For example, an amplifier may only be capable
of a sustained 100 watts, but may be able to achieve peaks of 200 watts for the
fraction of a second required for an intense, quick sound. In this example the
dynamic headroom would equal 3 db.
Dynamic Range
A measure in decibels
(db) of the bandwidth, or difference between the loudest and the quietest passages
in music. A wide dynamic range is preferable, as it more closely approximates
the original production.
Efficiency
A measure expressed in relative dB (decibels) of a speakers total output power
contrasted against its input power in RMS watts. Comparative measurements are
taken using 1 kilohertz, at one watt RMS, from 1 meter.
Enclosure
A speaker cabinet or box designed to create a proper resonance cavity to compliment
the charateristics of a woofer.
Equalization
A process that selectively
adjusts the gain of frequencies in the audio signal. An equalizer is often utilized
to compensate for deficiencies in room acoustics or the lack of speaker efficiencies.
Electrostatic Speaker: A speaker that radiates sound from a large
diaphragm that is suspended between high-voltage grids.
Euphonic
Pleasing. As a descriptive audio term, usually refers to a coloration or inaccuracy
that non-the-less may be sonically pleasing.
Extension
How extended
a range of frequencies the device can reproduce accurately. Bass extension refers
to how low a frequency tone will the system reproduce, high-frequency extension
refers to how high in frequency will the system play.
Fletcher-Munson
curve
Our sensitivity to sound depends on its frequency and volume. Human
ears are most sensitive to sounds in the midrange at around 1000 Hz. At lower
volume levels, humans are less sensitive to sounds outside the midrange; bass
and treble sounds produced with the same intensity, are perceived to be at lower
listening levels.
FM
Acronym for Frequency Modulation, the shorter
range transmission system (88 megahertz to 108 megahertz) utilized for audio and
video. Less susceptible to interference than A.M.
Foley Artist
Virtually all audio effects in a movie are created on a special soundstage (referred
to as a Foley Stage), and not during actual filming of the scene. Punches landing,
footsteps, bones breaking, car crashes, gunshots....all of these sounds are created
in studio by a Foley artist utilizing a variety of sometimes unorthodox tools.
The sound that you hear in a movie of bones breaking may actually be a crisp stalk
of celery being snapped. The dinosaurs grunts in Jurassic Park are actually a
mixture of the sounds of a variety of animals.
Frequency
A measurement
of the number of oscillations of an electromagnetic wave, expressed in cycles
per second, or hertz (hz) A 60 cycle frequency signal is characterized by a wave
that oscillates 60 times per second.
Frequency Response
Expressed
in hertz (hz) this is the measurement of the specific frequency bandwidth that
a transducer is capable of recreating. Frequency response often includes a measure
of db performance, ( plus or minus 3db) an indicator of how evenly, or flat the
audible range is reproduced. the default average for humans is 20 to 20,000 hz.
Full Bandwidth:
Bandwidth is the range of electronic signal frequencies
a particular component can reproduce. For audio components like receivers, "full
bandwidth" is generally considered to be the entire frequency range of human
hearing: 20 to 20,000 hertz.
Gain
A measure of signal amplification (loudness) that is expressed in decibels (db).
Harmonic
A sound wave
that is a multiple of the original frequency. ie: a 4khz signal is the first harmonic
of a 2khz frequency.
Heat Sink
A device for dissipating heat from
a transistor or amplifier
Headroom
The output level that allows
peaks in the signal to exceeds an amplifier's continuous operating rating momentarily
without overloading or distorting.
Hearing Sensitivity
The human
ear is less sensitive at low frequencies than in the midrange. Reducing volume
will cause the listener to 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
Hertz (hz)
A measurement standard that
is equal to the one cycle per second. One hertz is one cycle per second. 120 hertz
is 120 cycles per second.
High Pass Filter
A circuit that allows
only signals with frequencies above a predetermined level to pass through it.
Imaging
The extent to
which speakers can accurately locate, or place instruments or vocals to, in effect
create a soundfield in the room that is identical to the original recording.
Impedance.
Expressed in ohms, impedance represents the resistance to
the flow of current in the signal. Impedance includes resistance from any source,
including electrical capacitance and inductance and mechanical factors. Low impedance
is desirable for signal interfaces as it is more efficient and results in a more
accurate, noise free image.
In-Phase
Two or more signals that
have the same waveform and identical amplitude in synchronization.
Integrated
A/V Receiver
An audio component that combines pre-amplifier elements (multiple
inputs, built in tuners, equalization, source switching) and amplifiers in a single
unit.
Line Level
Any
signal at .5 to 8 volts AC from an input device that requires amplification before
it is sent to a speaker. Such signals are commonly exchanged among many types
of audio interfaces.
Linearity
A measure of the flatness of frequency
response of a signal, as an indicator of the accuracy of the signal being reproduced.
Low Frequency Effects Channel
The .1 of a Dolby Digital 5.1 channel
system. This is a stream of audio information that is limited in its frequency
response (20-120hz) and is dedicated solely for the reproduction of low frequency
special effects in the film.
Low Frequency Effects Woofer
The Low
Frequency woofer in a Dolby Digital Surround system is designed specifically to
reproduce 1 octave (20-120hz) bandwidth signals. Adds dramatic impact to car crashes,
gun shots, explosions etc.
Low Frequency Extension
Manufacturers,
writers and salespeople toss around all kinds of numbers and terminology that
can be very confusing and misleading. "This $300 shoebox sized sub is flat
to 20Hz" . Right, in your dreams . . . How is that cheap, tiny box and driver
going to reproduce a 56 foot wavelength with enough power to be heard? It will
not to it . Good bass reproduction requires moving a lot of air and playback at
realistic volumes. Remember the rule of needing to move four times the air to
go down one octave. Example: You have a pair of good quality tower speakers with
10" woofers that produce good bass down to around 40Hz. The salesman is telling
you that his little subwoofer with a single 10" woofer will extend your system
down to 20Hz. If you've been paying attention, you know that his woofer will have
to move eight times as much air as each of your 10" woofers, not likely.
Adding that subwoofer to your system mightgive you more apparent bass energy,
and in fact may help a little with movie special effects, but it is unlikely to
extend bass response significantly
Low Pass Filter
A circuit that
allows only signals with frequencies below a predetermined level to pass through
it.
Magnetic
Shielding:
Any
speaker within two feet of a TV screen should include magnetic shielding to prevent
color interference.
Matrixed
A process by which multiple signals are added,
or encoded into the Left or Right signals through a process of adding or subtracting
channel signals. This is the process that converts 4 channel Dolby Surround (Left,
Center, Right and Surround) signals into 2 channels (Left, Right) of information.
Modulation
The process of re-formatting audio or video signals
onto and into information carrying (generally FM frequency for video and home
theater audio products) signals. This is the method by which audio and video is
transmitted and/or recorded.
Muting
To greatly decrease the volume
level. Many receivers and pre-amplifiers have a muting control which allows the
volume level to be cut way down without changing the master volume control. Great
for when the phone rings.
Ohm
The unit of measurement for impedance, or resistance to the flow of electrical
current.
Out Of-Phase
Two or more signals that have the same waveform
and share opposing amplitude values at the same time. Like waves crashing on to
the shore meeting waves proceeding from the shore, out of phase signals that share
the same temporal identity can cancel each other out.
Passive
Radiator
A transducer (speaker) in a cabinet that relies on pressure generated
within the cabinet to reproduce low frequency signals. When done well, it reinforces
the bass wave. A speaker that is not connected to an amplifier, but accompanies
another in the cabinet that is connected to an amplifier.
Passive Subwoofer
A subwoofer that does not incorporate a built in amplifier, and therefore requires
external amplification.
PCM
Pulse Code Modulation. A means of
digital encoding
Perceptual Coding
The basis for Dolby Digital
data reduction, the fundamental concept behind Perceptual audio coding is to emphasize
sounds that we do hear in a signal and to strip away sounds that we do not hear,
and by doing so, take advantage of a limited amount of spectrum (384 kilobits
per second in a theater and 448 kilobits per second in DVD) to deliver multi-channel
audio information in a digital environment. Perceptual Coding employs a Data reduction
scheme that makes use of auditory masking and distribution of bits along narrow
frequency bands to match the requirements of reproducing the frequency range and
dynamic range of the coded audio . Channels that have higher frequency content
are allocated more bits in this codec; simultaneously this process allows higher
gain sounds that occur in one channel to provide for the masking of noise in another
channel.
Planar
A flat panel speaker.
Polypropylene
A synthetic material utilized in speaker cones. Characterized by light weight,
low resistance and minimum resonance, Polypropylene speakers offer the enhanced
elasticity necessary to reproduce fast transient signals.
Port
An opening in the speaker cabinet that allows the cabinet to "exhale"
low frequencies generated off the back of the speaker, extending bass response.
A ported cabinet generally allows higher power handling, higher speaker efficiencies
and improved low frequency performance. This function may also be performed by
a passive radiator (see above).
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
Power
Amplifier
The second stage of an integrated A/V receiver or a separate
unit. Amplifies low level signals received from the pre-amplifier.
Pre-amplifier
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. Magnetic phono cartridges always require equalization
preamps.
PWM
Pulse Width Modulation - another method employed in
diital amplifiers to shape sonic response.
Q
or Quality Factor Is a measure of damping. Modern home speaker systems have Q
values ranging from < .5 to approx. 2.0. Q values < .7 have no peak in the
response. Q values around .5 are considered to be optimally damped, having a Bessel
response. A Q of 1.0 is a Butterworth response. The lower the Q value, the better
the transient response of the system, (less or no ringing), but the tradeoff is
a larger required box size and the response begins to rolloff at a higher frequency.
Another way to consider it is that the lower the Q, the more gradual the rolloff
but the rolloff begins at a higher frequency.
Quantization
The
conversion of an analogue signal into a binary word of digital information.
Receiver
An audio component that
combines a pre-amplifier, amplifier(s) and tuner in one chassis. A Dolby Prologic
Receiver also contains a Dolby Prologic decoder for surround sound.
Resonant
frequency
Any system has a resonance at some particular frequency. At
that frequency, even a slight amount of energy can cause the system to vibrate.
A stretched piano string, when plucked, will vibrate for a while at a certain
fundamental frequency. Plucked again, it will again vibrate at that same frequency.
This is its natural or resonant frequency. While this is the basis of musical
instruments, it is undesirable in music-reproducing instruments like audio equipment.
Resistance
A
reduction in the flow of electrical current related to the inability of a given
conductor to carry it fully.
All materials are electrically resistive to some extent.
RMS (root-mean-square)
The square root of the mean of the sum of the squares. Commonly used as the
effective value in measuring a sine wave's electrical power. A standard in amplifier
output power and speaker power handling measurements.
Sampling
Frequency
A measurement of the number of times an analog waveform is sampled
by digital words to create a rendering of same.
Signal To Noise Ratio
The ratio, expressed in decibels between a signal's output gain, and the accompanying
noise contained within. A higher signal to noise ratio is desirable. A ratio over
80 dB is beyond the threshold of human perception.
Sensitivity
The amount of input signal strength, or gain required by a tuner or amplifier
to reproduce or achieve certain output levels. Expressed in microvolts, the lower
the rating, the higher the sensitivity of the device.
Another use of this
phrase is to describe the sound pressure levels (SPL) of a speaker at a pre-determined
distance and input..
Separation
The measurement (in decibels)
of the isolation between two signals. A signal with high separation will reproduce
a far more accurate and realistic stereo image. In order to deliver a passable
Dolby Surround matrix, a stereo signal must have at least 19db of separation.
Sound Waves
Sound waves can be thought of like the waves in water.
Frequency determines the length of the waves; amplitude or volume determines the
height of the waves. At 20Hz, the wavelength is 56 feet long! These long waves
give bass its penetrating ability, (why you can hear car boomers blocks away).
Speaker Cone
The conical surface of a common dynamic speaker (driver)
that radiates sound.
Spectral balance
Equal sonic pressure resulting
in balance across the entire frequency spectrum of the audio range.
SPL
(Sound Pressure Level)
A loudness scale relative to a standard input signal
consumption of 1 watt measured in decibels (db). SPL of speakers is measured utilizing
a 400hz tone one meter from the speaker along its front to center axis.
SubWoofer
A low frequency driver designed to reproduce low frequency, non directional (20
to 120hz) signals in an audio system. As a separate unit, it may have its own
dedicated amplifier.
THX
Acronym for Tomlinson Holman Experiment. Audio standard for surround sound system
that utilizes de-correlation (use of selective phase and gain shifting) to approximate
the audio tonalities of a large theater within a restricted spatial confines (and
smaller speakers) of a home theater.
THX Certification:
THX-certified
speakers meet the quality-control criteria defined by Lucasfilm, the company formed
by George Lucas creator of the Star Wars and Indiana Jones movies. Today,
there are more than 45 licensed manufacturers producing THX-certified components
for home theater systems
Timbre
The quality of a sound that distinguishes
it from other sounds of the same pitch and volume. The distinctive tone of an
instrument or a singing voice.
Total Harmonic Distortion
Measurement
of all of the distortion in a signal. Measured as a percentage of the overall
signal.
Transducer
A speaker, microphone, or phono cartridge. A
device that converts energy or signals from one form to another.
Transient
response
The ability of a component to respond quickly and accuratly
to transients, with minimal distortion. Transient response affects reproduction
of the attack and decay characteristics of a sound.
Transients
Bursts of high energy or spikes of gain in an audio signal. Frequently in the
low frequency range.
Triaxial (3-way) driver
Phrase utilized
to designate a speaker or speaker enclosure that features three drivers aligned
along the same axis.
Two Way Speaker System
A speaker that consists
of two drivers ( woofer and tweeter) and a passive crossover network that enables
each to reproduce a selected band of frequencies to maximize Linearity and frequency
response of the cabinet.
Tweeter
A cone, dome, or horn audio transducer
made to most efficiently produce the high end (4000 to 20,000 Hertz) of the audio
spectrum.
Voice Coil
The wire coil of a speaker that works in conjunction with the magnet to convert
electrical signals into mechanical energy. The resulting movement of the speaker
cone creates sound.
Warmth
A listening term. The opposite of cool or analytical. In terms of frequency, generally
considered the range from approx. 150Hz-400Hz. A system with the "proper"
warmth will sound natural within this range. This has also been a term used to
describe in positive terms, the distortions and colorations associated with vacuum
tubes.
Wavelength
The distance the sound wave travels to complete
one cycle. The distance between one peak or crest of a sine wave and the next
corresponding peak or crest. The wavelength of any frequency may be found by dividing
the speed of sound by the frequency. (Speed of sound at sea level is 331.4 meters/second
or 1087.42 feet/second).
Woofer
A low frequency speaker associated
with the production of signals from 20 to 150hz.
Y-Adapter
Any type of connection that splits a signal into two parts. An example would be
a connector with one male RCA plug on one end, and two female RCA jacks on the
other end.