5 PIN RELAY INFORMATION
Remote Turn-on: This schematic will give you a high voltage remote turn-on, which can be used for multiple amplifiers, or to use an existing low voltage
turn-on to create a high voltage turn-on without jeopardizing the current at the low voltage turn-on.
pin 87 - strong 12 volt source
pin 87a - n/a
pin 86 - current remote turn-on
pin 85 - ground
pin 30 - new remote turn-on
Switch a positive to a negative: This schematic will use an existing positive signal and convert it to a negative signal.
pin 87 - new negative
pin 87a - n/a
pin 86 - existing positive signal
pin 85 - ground
pin 30 - ground
Switch a negative to a positive: This schematic will use an existing negative signal and convert it to a positive signal.
pin 87 - new positive
pin 87a - n/a
pin 86 - existing negative signal
pin 85 - 12 volt source
pin 30 - 12 volt source
________________________________________________________________________________________________________
INDUSTRY TERMINOLOGY
AC: Alternating current. Energy that changes potential at a fixed or regulated rate. Both the electricity in a home, and a musical signal going to a speaker are
forms of alternating current.
Active
Crossover: A device built with
components, such as operational amplifiers and transistors, that requires an
external power supply.
Acoustical
Energy: Energy created by sound
waves.
Acoustics:
A science dealing with the study of
sound waves.
Advanced MOSFET OFR: A high-performance, amplifier power supply design that can efficiently provide the power needed by the amplifer, while running cool.
Advanced MOSFET OFR power supplies are used in
mobile audio amplifiers to allow maximum headroom and drive difficult loads.
Ammeter: A device used to measure current flow.
Amperage: A unit of electrical current
indicating the force through which energy is pushed through a conductor.
Measured in amps.
Ampere:
Unit of measurement used to determine
the quantity of electricity flowing through a circuit.
Amplification:
An increase in signal level.
Amplitude:
The measurement of the power of a
sound or electrical wave.
Analog:
An electrical signal where the frequency
and level vary in direct relationship to the original acoustical sound waves
that created the signal.
Anode:
The electrically positive terminal of an
electronic device.
Apex Off-Axial Tweeter: Coaxial speaker design where the tweeter is located in the base of the woofer cone. Apex mounting equalizes signal path length
differences of all frequencies handled by the
speaker. This ensures all frequencies reach the listener's ear at the same time
and improves stereo imaging.
Attenuate:
To reduce the force or volume of a
signal.
Audio Frequency
Spectrum: The range of human
hearing commonly accepted as 20 Hertz (cycles) to 20,000 Hertz (cycles).
Audio
Signal: The analog electronic
representation of a sound wave.
Bandpass: Allowing a certain range or band of frequencies to pass through a system, while blocking or restricting others. In audio, this can be done
electrically in a crossover, or mechanically as in a
bandpass subwoofer box.
Bandwidth:
The upper and lower usable frequency
limits of a device.
Basket:
The outside frame of a speaker that
supports the cone and the magnet.
Bass:
Low-frequency audio signals below 500Hz.
BL:
The electrical motor strength of a speaker.
Bridging:
Combining the outputs of two
amplification channels to provide one more powerful channel.
Butyl:
A type of rubber used for speaker
surrounds. Butyl has very good damping characteristics and is resistant to UV
contamination from the sun.
Capacitance:
The property of storing an
electrical charge between two separate conductors.
Capacitor: An electronic device that can store energy and release it as needed. A capacitor works by resisting a change in voltage, making it useful in
crossover circuits. Capacitors are rated in farads,
or more commonly microfarads or millionths of a farad.
Cathode:
The electrically negative pole of a
device.
Channel:
An amplifier section providing positive
and negative signal information for a speaker. Two channels are used to process
a stereo signal.
Chassis:
The metal frame of a vehicle.
Clamshell: Operating two subwoofers face to face on the same baffle board and electrically out of phase with each other. A type of "compound loading," it
allows a subwoofer to operate in a smaller
box.
Clipping: A distorted signal generated by an amplifier that is being operated over its capabilities. Clipping describes the actual "cutting off" of
signal peaks of an electrical signal at the amplifier's power limit. This is the sound often heard when a system is played too loud and the sound
starts to "break up." Clipping distortion is
the most common source of speaker damage.
CMS:
The mechanical compliance of a speaker
suspension.
Common Sense
Turn-on: The ability of amplifiers
or outboard devices to be turned on by an incoming speaker-level signal.
Compliance:
The volume of air in cubic feet that
is equal to the compliance of the total suspension of a speaker.
Component Speaker System: Separating the units of a coaxial speaker into a tweeter and a woofer or midrange driver. This allows for better
placement in a car environment, improving the stereo image.
Compound: Using two subwoofers coupled together in a small airspace. It allows a woofer to be used in a smaller enclosure. Compound loading
can be done by clamshelling or positioning the woofers front to
back.
Cone:
The part of a speaker that moves.
d: The system damping factor of a 4th order
bandpass box.
Damping:
The reduction of resonant energy in a
speaker, or between a speaker and amplifier.
DC:
Direct Current. Power derived from a battery
or rectified source where electrons flow only in one direction.
DC
Resistance: The resistance a device produces
for a DC current. Direct measurement by a digital multimeter or a volt/ohm meter
gives DC resistance.
Decibel: A measurement of sound pressure, or relative intensity of sound. It should be noted that decibels are logarithmic in nature. An increase of 10dB from
a certain point represents a doubling of sound
output. From an audio standpoint, doubling the sound output of a system will
require 10 times the power.
dB:
Decibel.
DMM:
Digital Multimeter. A digital meter that
"samples" electrical input to give very accurate readings of voltage,
current, or ohms.
Dia:
The usable piston diameter of a driver.
Die Cast Aluminum Baskets: Driver baskets that are cast from aluminum. Cast baskets are much stronger than stamped steel and allow for tighter
production tolerances and precise driver operation under even
the most demanding situations.
Differential Input Circuit: A circuit used by amplifiers that re-creates a preamp-level signal from a high-level signal that is of preamp quality.
This method produces a signal that is much lower in
distortion than the methods commonly used in other amplifiers.
Diode:
An electronic device that blocks current
flow in one direction, but allows it in another.
Discrete Circuitry: The use of separate components such as resistors, capacitors, and diodes instead of ICs (Integrated Circuits) which
"print" these components in microscopic size on a chip. Discrete components allow for tighter tolerances, and higher performance (especially in
amplifier output stages), are less heat sensitive, and make
better-sounding components.
Distortion: Sound that has been changed from the original performance. The three major forms of electronic distortion in audio are
clipping distortion, harmonic distortion, and intermodulation distortion.
Driver:
Another name for a speaker.
Dv:
The inside diameter of a vent or port.
Dynamic
Range: The difference between the
loudest and softest sounds that can be reproduced by a device or format.
E-M:
The electro-mechanical parameters of a
loudspeaker.
EBP:
The efficiency bandwidth product. (Fs/Qes)
Edgewound Ribbon Voice Coil: A practice where wire is flattened into a metal ribbon and then wrapped on edge to form a voice coil. This allows for
the greatest amount of wire to be located in the gap,
increasing performance.
Efficiency:
The measure of an amplifier or
speaker's ability to convert input power to work. Expressed as a percentage.
Electrolytic Capacitor: The most common form of capacitor consisting of a conductive film in an electrolyte. These are canister-shaped and
come in the widest range of values. Stiffening caps are
electrolytics.
Excursion:
The amount of movement a speaker cone
is capable of.
Extended Pole Piece: A design innovation that allows for increased excursion while decreasing distortion by operating the
voice coil over a longer throw.
Fb:
The resonant (tuned) frequency of a vented
box. Expressed in Hertz (Hz).
Fc:
The resonant frequency of a sealed box.
Expressed in Hertz (Hz).
F3:
The half power (-3dB) of a loudspeaker
enclosure design. (Hz)
Fp:
The free-air resonant frequency of a passive
radiator. (Hz)
Fs:
The free-air resonant frequency of a driver.
(Hz)
Farad:
The basic unit of capacitance. Outside of
stiffening caps, the most common values of capacitors are in microfarads, or
millionths of a farad.
Fill: Polyfill or something similar used to "stuff" a box. When placed inside a box, fill makes the box seem larger to the woofer, and helps
break up standing waves within the box.
Flat Response: The ability of a speaker or amplifier to reproduce all points of the frequency band equally, without dips or peaks when
referenced to the original input.
Free Air
Resonance: The frequency at which a
driver will naturally resonate.
Frequency:
The number of vibrations or cycles
completed by a signal in one second. Frequency is expressed in cycles, or more
commonly, Hertz (Hz).
Frequency Response: The usable frequency bandwidth of a speaker, amplifier, or source unit. Usually stated as lower to upper frequency with a
deviation in decibels, or relative loudness. Example:
Frequency Response of 10Hz to 40kHz +/- 1dB.
Fuse:
A device designed to protect other
electronic devices by melting and opening the circuit when the system is drawing
too much power.
Gain:
The amount of amplification applied to a
signal.
Gap:
The space between the magnet and the pole
piece in a speaker's motor assembly that houses the voice coil.
Generator:
A rotating device that creates DC
current.
Ground:
Any place having an electrical potential
of zero. In mobile audio, ground is typically used as the term for the vehicle
chassis.
Ground
Loop: A situation where electrical
potential exists between two grounding points on the same vehicle.
Harmonic:
A weaker overtone or undertone of a
musical note that is responsible for the character or texture of the note.
Harmonic Distortion: Distortion that is harmonic in nature, following the natural harmonics of the original signal.
This is the
least noxious form of distortion.
Head
Unit: A factory or aftermarket car radio,
especially with CD or cassette.
Hertz
(Hz): The basic unit of frequency. The
number of full cycles completed by an alternating signal in one second.
High Current Design: An amplifier that is able to supply the electrical current demanded by a reactive, low impedance driver,
while maintaining output voltage.
High
Frequency: The highest audible frequencies.
Generally accepted as those over 5,000 Hz.
High Pass
Filter: A device or network of
components that blocks low (bass) frequencies below a designated point, and
allows high frequencies to pass.
High-Polymer Laminate: A type of speaker cone that consists of a natural substrate with a coating of a special polymer to reduce cone resonance
and increase strength. HPL cones are extremely durable and
keep their shape under extreme conditions, providing tight bass and excellent
dynamics.
Imaging: The sensation, provided by a well-designed, high-quality audio system, that the performers on the recording are actually
performing in real space in front of the listeners.
Impedance:
The resistance of a device to the
flow of alternating current. Often used to rate the resistance of a speaker's
voice coil.
Inductive
Coupling: Noise that is transmitted
through a magnetic field to surrounding wires.
Inductor (Coil): An electrical component which increases impedance with an increase in frequency. Often used in passive crossovers,
inductors are rated in henries.
Infinite Baffle: A speaker mounted in a board with no side or rear panels. Also called "free-air." Technically speaking, a speaker can be considered
infinite baffle if it is in a sealed
enclosure that is larger than the Vas of the driver.
Intercooling:
A design feature of subwoofers
that draws cooling air into the motor structure and vents out heated air.
Intermodulation Distortion: Distortion created by a device that is not harmonic with the original signal. Since it is not harmonics of the original
signal, intermodulation distortion is often described as "harsh and grating," and tends to be more noticeable than harmonic distortion.
Intermodulation distortion is often the result of poor amplifier design or the use of excessive amounts of negative feedback in the circuit. Systems that are
fatiguing to listen to often have high rates of intermodulation
distortion.
Intermount: A speaker mounting system has been developed where a mounting ring is first fastened to the car and the speaker is fastened to
the mounting bracket. This method not only allows for easier installation, but in the case of Intermount II, allows for the use of a larger cone
in the speaker, creating added efficiency and bass response.
Isobaric: The mounting of two speakers in a way that will couple their output. This can be done by mounting the drivers in a back-to-front, or
front-to-front (clamshell) arrangement with the drivers mounted out of phase with each other. This method of box construction allows the use of a
smaller than normal box.
Joule:
A unit of energy that equals one watt
delivered in one second.
Kevlar Cones: Constructing speaker cones using Kevlar. Kevlar is an aramid fiber that is extremely strong and light, making it an excellent choice
for speaker cones and bullet-proof vests.
Kirchoff's Current
Law: All current entering a
point in a circuit must equal the sum of all the current leaving that point.
Kirchoff's Voltage
Law: The voltage applied to a
DC circuit must be the same as all of the voltage drops within the circuit.
kHz:
Abbreviation for kilohertz or thousands of
Hertz or cycles.
Le:
The inductance of a voice coil.
Lv:
The length of a vent or port.
Loudspeaker:
An electro-acoustic transducer that
converts an electrical signal to audible sound waves.
Low
Frequency: Generally refers to sound within
the 40Hz to 160Hz band.
Low Pass
Filter: A device or network of
components that block high frequencies at a designed point, and allows bass
frequencies to pass.
Mms:
The mechanical mass of a loudspeaker
diaphragm including air load.
Magnet:
The device at the back of a speaker that
provides a stationary magnetic field to attract or repel the voice coil as the
signal passes through it.
Midrange
Driver: A speaker that is designed to
reproduce midrange frequencies, where most musical information lies.
Midwoofer: A speaker that is designed to reproduce the upper bass frequencies, typically between 80Hz and 200Hz. Small subwoofers are often
used as midwoofers in order to integrate a larger woofer,
or add midbass "punch."
Milliamps:
Thousandths of an amp.
Mineral Filled Co-Polymer
Cone: A very light and
rigid cone material that combines high strength and exceptional damping
characteristics.
Multiple Power Supplies: Putting more than one power supply in an amplifier. We often use multiple power supplies on large amplifiers to improve
performance in difficult situations.
No:
The reference efficiency of a driver with a
half-space acoustical load.
Negative Feedback: The practice of returning some of an amplifier's, or amplifier stage's, output to its input 180 degrees out of phase. This has a tendency
to reduce distortion and make an amplifier more stable. Too much reliance on negative feedback results in very high IM (intermodulation distortion)
readings, and poor sonic performance.
Neodymium:
A rare earth magnet that is 10 times
stronger than standard ferrite magnets.
Nominal
Impedance: The stated impedance rating
of a speaker. This is used by a manufacturer to represent the load the speaker
will provide to an amplifier.
Octave:
A doubling or halving of frequency.
Example: 80Hz is one octave above 40Hz.
Ohm:
Basic unit for measuring resistance.
Ohm's Law: The basic relationship between current, voltage, and resistance. Ohm's law states that voltage = current x resistance,
current = voltage/resistance, and resistance = voltage/current.
Pe:
The maximum continuous (RMS) power-handling
capability of a speaker.
Parallel
Wiring: Connecting two or more devices
to a common voltage point so that each device carries the full applied voltage.
Pass
Band: The band of frequencies that a
bandpass crossover or bandpass speaker enclosure will allow to pass.
Passive Radiator: Often called a "drone cone." A speaker with no motor assembly that resonates in response to a driven speaker in an enclosure.
Passive radiators act very much like a vent or
port in a speaker.
Peak:
An emphasis on a relatively narrow band of
frequencies, typically less than one octave in width.
Period:
Amount of time required for one cycle of
a sound wave to occur.
Phase: The timing of a sound or electrical wave. Phase is measured in degrees, from 0 to 360. 180 degrees would be perfectly out of phase and
often causes signal cancellation in lower frequencies.
Parallel Sixth Order Bandpass
Enclosure: The
most common type of sixth order enclosure where both vents or ports fire outside
the enclosure.
Polarity:
Being electrically positive or
negative.
Pole
Piece: The metal pole attached to the
magnet structure in a speaker's motor assembly that is surrounded by the voice
coil, forming the inside wall of the gap.
Poly-tex: Textured polypropylene speaker cones. The textured surface helps to break up harmonic resonances that travel along the cone surface,
improving midrange response.
Port:
A vent or tube tuned to extend the usable
response of a woofer in an enclosure.
Potentiometer:
A variable resistor used to
attenuate a signal.
Power:
The amount of energy in Joules that a
device uses or delivers divided by the time the energy was used or delivered.
Power Line
Noise: Varying AC noise in a car that
is heard as a whining that increases or decreases with engine speed.
Power PMP Cones: Injection-molded PolyMethlyPentene woofer cones. PMP is much lighter and stiffer than either polypropylene or paper, resulting in
excellent transient and bass response.
PMP's superior damping characteristics also dramatically improve midrange
clarity.
Pre-Amp
Outputs: Facilities on an amplifier,
signal processor, or source unit that pass a low level signal to an amplifier
for further amplification.
Pure Titanium Dome
Tweeters: Titanium is
extremely light and stiff, making it an excellent choice for making tweeters.
Push-Pull
Configuration: See Clamshell.
Q:
System losses or relevant damping in an
enclosure. Defined as the ratio of stored to dissipated energy.
Qec:
The Q of a speaker in a sealed box
considering only electrical resistance.
Qes:
The Q of a speaker at Fs considering only
electrical resistance.
QL:
The Q of a vented box resulting from box
losses.
Qt:
The total Q of a speaker's suspension when
considering the load of the sealed chamber of a 4th order enclosure.
Qmc:
The Q of a speaker in a sealed box
considering only mechanical resistance.
Qms:
The Q of a speaker at Fs considering only
mechanical resistance.
Qtc:
The Q of a speaker in a closed box
considering both electrical and mechanical resistance.
Qts:
The Q of a speaker at Fs in free air
considering both electrical and mechanical resistance.
Quiescent
Current: Amount of current a device
consumes when not doing work.
RCA Connectors: A wire consisting of 2 conductors, usually used to connect a low level output source unit to a low level input on a processor or
amplifier source.
Re:
The DC resistance of a speaker voice coil.
Rms:
The mechanical resistance of a speaker's
suspension losses.
Remote
Out: A "turn on signal" source
for amplifiers and signal processors.
Resistance:
The property of some materials to
restrict the flow of electricity. Measured in ohms.
Resonance:
The tendency of an object to vibrate
at a certain frequency.
Ripple:
Any deviation from flat response in a passband.
Rip Stop
Spiders: Spiders made of high strength
synthetic (often aramid based) materials that are resistant to tearing.
RMS:
Root Mean Square. Method used to calculate
continuous average power output of an amplifier.
Roll-off:
The attenuation of frequencies above
or below a certain point.
Sd:
Piston area of a speaker.
Sens:
Sensitivity
Sensitivity: A measurement of the sound output of a speaker or speaker system's output relative to the power put in. Typically measured in dB
at 1 watt of input, 1 meter away.
Series
Wiring: A circuit where components are
wired sequentially, dividing the voltage between them.
Series-Parallel: A circuit where there are components wired in series and in parallel to get the desired result. This is often used in multi-woofer systems to
optimize the impedance seen by an
amplifier.
Series Sixth Order
Enclosure: An enclosure
consisting of a vented box with its port firing into another vented box.
Short Circuit: The situation that occurs when there is an alternate path created between the positive and negative portions of a circuit, bypassing some or all of
the components of the circuit and preventing
operation.
Simultaneous Stereo/Mono: The ability of an amplifier to drive three speakers from two channels, deriving either a subwoofer or center channel signal
from the two other channels.
Small, R.H.: A pioneer in the study of the relationships of speakers and enclosures. Along with A.N. Theile, Small spelled out what is still the basis for
speaker enclosure design.
Sound: Acoustical energy in waves generally accepted to be between 20 and 20,000 cycles per second.
SQ (Sound Quality): Defined as the degree of accuracy with which a device records or (in car audio's respect) emits the original sound waves. This
measurement is usually a points score based on many factors. Some of these factors are judged by the ear (like sound stage height, width, and center
focus) while others are judged by electronic devices such as RTA's (real-time analyzer).
SPL (Sound Pressure Level): The acoustic measurement for sound output. It is measured in dB (decibels), the readings are often "weighted" to reflect how
human ears work.
Spider: The part of the speaker attached to the
junction of the cone and voice coil that keeps the voice coil aligned in the gap
and helps suspend the cone.
SPL:
Sound Pressure Level
Subwoofer:
A speaker or speaker/enclosure system
designed to reproduce only bass frequencies. Generally used only below 80Hz.
Symmetrical Field Geometry: A speaker motor assembly design that maintains equal magnetic force throughout the travel of the voice coil. This
improves bass response and substantially reduces distortion.
Theile-Small
Parameters: A series of driver
measurements developed by A.N. Thiele and R.H. Small that models how a speaker
will work with an enclosure.
Thiele,
A.N.: A pioneer in studying
speaker/enclosure relationships. Along with R.H. Small, defined what is
currently accepted as the basis for enclosure design.
Titanium: A strong, lightweight metal, often used in high-stress situations, e.g., in the manufacture of space vehicles, race cars, airplanes, and
medical replacements.
Titanium Composite: Combination of titanium and a special polymer. This material benefits from the strength and lightness of titanium as well as the damping
qualities
of a polymer to make tweeter
diaphragms and speaker cones that are strong, lightweight, and capable of
extremely accurate reproduction.
Titanium Composite Injection Molded Curvilinear Cones: Speaker cones made from a titanium/polymer composite that are molded into a curvilinear
shape and result in a strong lightweight cone that is capable of excellent bass
and transient response, as well as a clear uncolored midrange.
Universal Interface: An innovation that allows amplifiers and other outboard electronics to operate from any type of input from a factory car stereo.
The Universal Interface will create a pre-amp quality
signal from high power, standard power, or balanced outputs.
Vap:
Volume of air having the same compliance as
the suspension of a passive radiator.
Vas:
Volume of air having the same compliance as
the suspension of a speaker.
Vb:
Internal volume of a box with a vent or
passive radiator.
Vc:
Internal volume of a sealed box.
Voice Coil: A coil of wire attached to the rear of the speaker cone that works with the magnet to provide a motor to drive the speaker. The hookup wires
for a speaker connect the head unit or amplifier
output to the voice coil.
Voltage:
Electrical pressure that can do work.
Voltage
Drop: The amount of energy used by a
device that has resistance in a circuit.
Volt:
The basic measurement of electrical
pressure in a circuit.
Volume:
Number of cubic feet, cubic inches, or
liters of space in a speaker enclosure.
VOM:
Volt-Ohm Meter. An analog meter that reads
Voltage, Ohms, and Milliamperes.
Watt:
The basic measuring unit for electrical or
acoustical power.
Wattage:
Electrical power.
Waveform:
The shape of a sound or electrical
wave.
Woofer:
A speaker that is designed to reproduce
bass frequencies. Generally refers to a large dynamic driver.
Xmax:
The amount of linear travel a cone can
make while still being controlled by the voice coil.
Z: The nominal impedance of a driver.
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