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Built-in
Crossovers |
Often
used to keep high-frequencies from reaching a subwoofer.
A low-pass crossover allows only low frequencies to be amplified.
A high-pass crossover allows only high frequencies to be amplified.
It keeps low bass away from small speakers, so they can play
more efficiently.
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Bridged
Power |
Bridging
a car amplifier, combines the power output of two channels
into one channel. Bridging allows the car amplifier to drive
one speaker with more power than the amp could produce for two
speakers. Because of this high power output, bridging is the
best way to drive a single subwoofer. Bridging a car amplifier,
combines the power output of two channels into one channel.
Bridging allows the car amplifier to drive one speaker with
more power than the amp could produce for two speakers.
Because of this high power output, bridging is the best way
to drive a single subwoofer. If the amp is bridgeable, the owner's
manual will have directions that tell you how.
Also, keep in mind that most car amplifiers need to see a 4-ohm
load when bridged to mono operation. If you want to bridge your
amp, you should use one 4-ohm speaker or, if you prefer multiple
woofers, wire two 8-ohm speakers in parallel. (Consult your
manual before operating your car amp in bridged mode.)
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Discrete
Output Devices |
There
are 2-3 basic types of output devices found on car audio amplifiers
1). integrated circuits, 2) bipolar transistors, or MOSFETs.
An integrated circuit (or IC) is found only on relatively low-wattage
(20 watts RMS per channel or less) amplifiers called "bridged
transformerless" amps. An IC can not pass enough current to
work on a more powerful amp and is not considered a discrete
output device. Bipolar transistors and MOSFETs are found on
the output stages of high powered amplifiers. They are fast
enough and can handle enough current to send wattage greater
than 20 watts per channel to your speakers. Both of these types
of transistors are considered discrete output devices. Usually
there are two per channel, but some amps feature as many as
four per channel.
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Mono
Amplifier |
Mono (or
monaural) car amplifiers are single channel amps, well-suited
for low-frequency applications. Mono car amplifiers are stable
to 2-ohms so you can connect them safely to two 4-ohm woofers
wired in parallel.
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MOSFET
|
(Metal
Oxide Semiconductor Field Effect Transistor) A type of large
output transistor used in the final stages of many power amplifiers,
and commonly found in most car amplifiers today. Mosfet transistors
are most often discrete devices, used with smaller driver
transistors and other devices, to convert a small signal to
a large one. They are highly stable and efficient, compared
to the bipolar types that preceded them.
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Ohm |
The
measurement of electrical resistance and system impedance.
It is a measure of the degree to which electrons are limited
in both velocity and quantity in passing through a circuit.
In Impedance measurements, this takes into account, the mechanical
resistance inherent in the motion of transducers. The standard
is usually 4 ohms for car audio.
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Parametric
|
A
type of equalization that permits the center frequency, the
filter shape, and the amplitude of each band to be varied. This
gives you extremely precise control of the tonal balance in
your vehicle. (More versitile than graphic equalizers)
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Preamp
output |
This
is the first stage of amplification in which the amplitude of
a very low-level audio signal is increased. The first stage
of amplification in which the amplitude of a very low-level
audio signal is increased.
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RMS
Power |
The
higher the RMS figure, the louder and cleaner your music sounds.
The RMS rating is the maximum the amplifier can put out all
day long without distorting. The RMS rating is very important.
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Peak
Power |
The
peak power rating tells you the maximum wattage a car amplifier
can deliver as a brief burst The RMS rating is more important.
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Signal-to-Noise
Ratio |
A
measurement of noise level in a device compared to the level
of the signal. Higher numbers signify a greater difference,
which is better.
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Speaker
input |
Speaker
inputs let you connect an amp to a receiver that lacks RCA preamp
outputs.
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Total
Harmonic Distortion (THD) |
The
THD is usually expressed in dB. the ratio of (a) the sum of
the powers of all harmonic frequencies above the fundamental
frequency to (b) the power of the fundamental frequency
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Tri-Way
Output |
Car
Amplifier setup that powers a pair of stereo speakers and one
subwoofer simultaneously from the outputs of a single 2-channel
amplifier. |
