openbsd-flipp
09-09-2004, 07:25 PM
Q: What do the acronyms mean?
A:
1.“A” is for amperes, or current. Current is the amount of flow. Current is measured in amps “A”
2.“V” is for voltage. Voltage is the amount of push on the electrons. Voltage is measured in volts “V”
3.“R” is for resistance. Resistance fights against the flow and push of a circuit. Resistance is measured in Ohms “?”
4.“DC” is direct current. DC circuits are directional. DO NOT plug a DC circuit in the wrong way of you WILL blow components. Cars are either 12v(most common), 16v(usually race cars), and 24v(dual alternator) and ALL are DC.
5.“AC” is for Alternating current. This is your house power. You can plug in backwards to no ill effect
6.“W” is for Watts. Watt is the measurement of electrical power.
7.“Hz” is for Hertz. Hertz is the frequency
8.“dB” is for decibel. Decibels is a logarithmic measurement for power ratios.
9.“SPL” is sound pressure level and is similar to dB. SPL measurements are also ratios, but are always measured relative to a constant.
10.“THD” is for total harmonic distortion, and is a measure of the how much a certain device may distort a signal.
11.An Ohm “?” is a measure of resistance and impedance, which tells you how much a device will resist the flow of current in a circuit.
What is meant by “frequency response”?
The frequency response of a device is the range of frequencies over which that device can perform in some fashion. The action is specific to the device in question. For example, the frequency response of the human ear is around 20Hz-20kHz, which is the range of frequencies which can be resolved by the eardrum. The frequency response of an amplifier may be 50Hz-40kHz, and that of a certain speaker may be 120Hz-17kHz. In the car audio world, frequency responses should usually be given with a power ratio range as well, such as (in the case of the speaker) 120Hz-17kHz +/-3dB. What this means is that given an input signal anywhere from 120Hz to 17kHz, the output signal is guaranteed to be within an "envelope" that is 6dB tall. Typically the extreme ends of the frequency range are the hardest to reproduce, so in this example, the 120Hz and 17kHz points may be referred to as the "-3dB points" of the amplifier. When no dB range is given with a frequency response specification, it can sometimes be assumed to be +/-3dB.
A:
1.“A” is for amperes, or current. Current is the amount of flow. Current is measured in amps “A”
2.“V” is for voltage. Voltage is the amount of push on the electrons. Voltage is measured in volts “V”
3.“R” is for resistance. Resistance fights against the flow and push of a circuit. Resistance is measured in Ohms “?”
4.“DC” is direct current. DC circuits are directional. DO NOT plug a DC circuit in the wrong way of you WILL blow components. Cars are either 12v(most common), 16v(usually race cars), and 24v(dual alternator) and ALL are DC.
5.“AC” is for Alternating current. This is your house power. You can plug in backwards to no ill effect
6.“W” is for Watts. Watt is the measurement of electrical power.
7.“Hz” is for Hertz. Hertz is the frequency
8.“dB” is for decibel. Decibels is a logarithmic measurement for power ratios.
9.“SPL” is sound pressure level and is similar to dB. SPL measurements are also ratios, but are always measured relative to a constant.
10.“THD” is for total harmonic distortion, and is a measure of the how much a certain device may distort a signal.
11.An Ohm “?” is a measure of resistance and impedance, which tells you how much a device will resist the flow of current in a circuit.
What is meant by “frequency response”?
The frequency response of a device is the range of frequencies over which that device can perform in some fashion. The action is specific to the device in question. For example, the frequency response of the human ear is around 20Hz-20kHz, which is the range of frequencies which can be resolved by the eardrum. The frequency response of an amplifier may be 50Hz-40kHz, and that of a certain speaker may be 120Hz-17kHz. In the car audio world, frequency responses should usually be given with a power ratio range as well, such as (in the case of the speaker) 120Hz-17kHz +/-3dB. What this means is that given an input signal anywhere from 120Hz to 17kHz, the output signal is guaranteed to be within an "envelope" that is 6dB tall. Typically the extreme ends of the frequency range are the hardest to reproduce, so in this example, the 120Hz and 17kHz points may be referred to as the "-3dB points" of the amplifier. When no dB range is given with a frequency response specification, it can sometimes be assumed to be +/-3dB.