So in another post I gave some laymen's terms as to what the differences were between the Class A, AB, and Class D amps, and I left out Class C, as they are coming, but they are more complicated and have yet to prove themselves.
But when you do decide on the power configuration and price, which one should you buy?
I borrowed these specs below from an amp, and in very basic terms I am going to break down what all of the specs mean and why you would care.
These are pretty straight forward. This is how much power, supposedly this amp will put out. If the company does not participate in the CEA standards, then it is really hard to gauge if the numbers are real or not. My learned collogue has stated 1 watt can fill a room, and he is 100% correct. That comes down to how efficient the amp is and we will get to that spec shortly.
• RMS Power @ 4 Ohms : 340W x 1
• RMS Power @ 2 Ohms : 570W x 1
• RMS Power @ 1 Ohms : 820W x 1
• RMS Power @ 1 Ohms @ 16V : 1000W x 1
This is how much power from the battery you can feed into this amp. While 16 volts seems unreachable for us in our Fiesta, I found the 8.5 volts very interesting. This means if you were sitting somewhere and were in the process of killing your battery, this thing would continue to play. Im certain their are other uses besides the car, but for our conversation, anything between 11V-15V is good to go.
• Working Voltage : 8.5V-16V
This one is pretty important. You obviously would not want this amp for playing your tweeters or midrange, however, it can clearly play your midbass or subbass speakers. For our car, if you have any plans to replace your factory speakers other than adding a subwoofer, you might consider other options like a 5 channel or 6 channel for no other reason, is the power requirements to run multiple amps is quite large and serious drain on the charging system. It can be done but at great expense like upgrading the alternator, adding a second batter, installing caps, etc.
• Frequency Response : 15~270Hz
While this spec may not mean much to some, it is very important to an audiophile. The Signal to Noise ratio is in effect how quiet the amp is. You want this number to be as high as possible. The higher the better the lower the worse. Without getting scientific, in laymen’s terms, this is a measure of how much useful information there is an a system. While it is not the only factory, if you get a test CD that has a track that has 0 data on the track and play it at maximum volume, the better this number the quieter the system hiss will be. And you might say, why would I care, because the system hiss is there when their is music playing, even on a subwoofer.
• Signal to Noise Ratio : 85< dB
While Damping Factor is not a major spec when it comes to highs and mids, it is very important when it comes to subs. As a matter of fact probably the most important spec. This is basically the amplifiers ability to control overshoot of the speaker to stop the cone from moving. Cone control is everything with a subwoofer. It is what gives the subwoofer the ability in conjunction with the speakers spider to control the movement of the sub so it is not just flapping around. The more control the better. Most good amplifiers will have a damping factor above 500. Some get up to 1000. higher is better.
• Damping Factor : 150< • Efficiency @ 4 Ohms : 85%<
I have said many times, it is all about the signal voltage into an amp. The more signal voltage you can feed into an amp, the more the Signal to Noise matters. Your Fiesta puts out about 2 volts of signal. While that is ample to get noise out the system. 4 volts is more preferable, and 8 is better. No one makes an head unit that puts out 8 volts of signal. Kenwood and Pioneer each make a deck that puts out 5 volts. The more voltage the lower the gain can be set, the quieter the amp is. More music for your ears less noise.
• Low Level Input : 6V-0.2mV
This is a useful feature, especially if you are going to be running multiple sub amps. This amp will allow you to daisy chain amps. Taking your RCA's into the amp, and allowing you to run an RCA out to another amp.
• Line Output : Yes
The Low pass Filter is the subwoofer crossover points, and if it is a multichannel full range amp, the amp will most likely offer High, and low, and subwoofer crossover adjustments.
• Low Pass Filter @24dB Slope : 35~250Hz
Bass boost in this case at 45 hertz, is nothing more than a built in EQ at that frequency point. In this case, the amp allows you to raise the effective volume by adding 9db of gain to the output.
• Bass Boost @ 45Hz : 0~9 dB
Subsonic filters are one of the most misunderstood specs on an amp. Obviously all subwoofers are not created equal. All play bass, but some do it better than others. Some are built to handle large amounts of peak power, and others are not. A subsonic filter is a high pass crossover for subwoofers, The lower you go in frequency, the longer the sound wave, and the more the speaker cone will move and depending on the speaker you purchase excess movement can damage the speaker, spider, or voice coil. The subsonic filter allows you to add a high pass crossover to the subwoofer to prevent it from playing too low.
• Subsonic Filter @24dB Slope : 10~50Hz
Phase shift is another misunderstood concept. Sound waves are either in phase with normal waves or out of phase by a certain amount of degrees. When you install speakers in cars, the phase of the speakers can change just by their location. This adjustment will allow you to make modifications to the phase of the wave output to bring your speaker more in line with the rest of the system. You might ask how in the world could you do that with your ears alone. So first an example of what your doing when you adjust the phase. If you took two identical speakers and sat them on the floor, and wires one of them in reverse, They would cancel each other out and the bass would be minimum. When your listening in the car and adjusting, the bass location will appear to move from the back of the car to the front of the car the more you go out of phase, because you are in affect changing the localization effect of the sound wave.
• Phase Shift : 0~180
This amp has the ability to act as a master with additional slave amps connected to it, so you could control all of the amps from one.
• Degree's Master/Slave (Strappable) : Yes
It is what it say it is, this is a remote bass knob that allows you to adjust the gain control of the bass boost remotely.
• Remote Level Control (Bass Knob)
And lastly, very importantly the input size of the wire the amp will allow. Do's. Use the largest wire the amp will take. Use the same size wire you used for power or larger wire for ground. Dont's DO NOT TRY TO POWER THE AMP FROM YOUR FUSE BOX. Make sure you install a fuse at least of the maximum amount the amp will draw installed at least no more than 18" from the battery and 18" from the amp. The fuses in the amp protect the amp circuit. If their is a short in the power line, The fuses in the amp will not save your amp from being fried.
• Power & Ground Input : 4 Gauge
• Dimensions (mm) : 250L x 241W x 64.5H
But when you do decide on the power configuration and price, which one should you buy?
I borrowed these specs below from an amp, and in very basic terms I am going to break down what all of the specs mean and why you would care.
These are pretty straight forward. This is how much power, supposedly this amp will put out. If the company does not participate in the CEA standards, then it is really hard to gauge if the numbers are real or not. My learned collogue has stated 1 watt can fill a room, and he is 100% correct. That comes down to how efficient the amp is and we will get to that spec shortly.
• RMS Power @ 4 Ohms : 340W x 1
• RMS Power @ 2 Ohms : 570W x 1
• RMS Power @ 1 Ohms : 820W x 1
• RMS Power @ 1 Ohms @ 16V : 1000W x 1
This is how much power from the battery you can feed into this amp. While 16 volts seems unreachable for us in our Fiesta, I found the 8.5 volts very interesting. This means if you were sitting somewhere and were in the process of killing your battery, this thing would continue to play. Im certain their are other uses besides the car, but for our conversation, anything between 11V-15V is good to go.
• Working Voltage : 8.5V-16V
This one is pretty important. You obviously would not want this amp for playing your tweeters or midrange, however, it can clearly play your midbass or subbass speakers. For our car, if you have any plans to replace your factory speakers other than adding a subwoofer, you might consider other options like a 5 channel or 6 channel for no other reason, is the power requirements to run multiple amps is quite large and serious drain on the charging system. It can be done but at great expense like upgrading the alternator, adding a second batter, installing caps, etc.
• Frequency Response : 15~270Hz
While this spec may not mean much to some, it is very important to an audiophile. The Signal to Noise ratio is in effect how quiet the amp is. You want this number to be as high as possible. The higher the better the lower the worse. Without getting scientific, in laymen’s terms, this is a measure of how much useful information there is an a system. While it is not the only factory, if you get a test CD that has a track that has 0 data on the track and play it at maximum volume, the better this number the quieter the system hiss will be. And you might say, why would I care, because the system hiss is there when their is music playing, even on a subwoofer.
• Signal to Noise Ratio : 85< dB
While Damping Factor is not a major spec when it comes to highs and mids, it is very important when it comes to subs. As a matter of fact probably the most important spec. This is basically the amplifiers ability to control overshoot of the speaker to stop the cone from moving. Cone control is everything with a subwoofer. It is what gives the subwoofer the ability in conjunction with the speakers spider to control the movement of the sub so it is not just flapping around. The more control the better. Most good amplifiers will have a damping factor above 500. Some get up to 1000. higher is better.
• Damping Factor : 150< • Efficiency @ 4 Ohms : 85%<
I have said many times, it is all about the signal voltage into an amp. The more signal voltage you can feed into an amp, the more the Signal to Noise matters. Your Fiesta puts out about 2 volts of signal. While that is ample to get noise out the system. 4 volts is more preferable, and 8 is better. No one makes an head unit that puts out 8 volts of signal. Kenwood and Pioneer each make a deck that puts out 5 volts. The more voltage the lower the gain can be set, the quieter the amp is. More music for your ears less noise.
• Low Level Input : 6V-0.2mV
This is a useful feature, especially if you are going to be running multiple sub amps. This amp will allow you to daisy chain amps. Taking your RCA's into the amp, and allowing you to run an RCA out to another amp.
• Line Output : Yes
The Low pass Filter is the subwoofer crossover points, and if it is a multichannel full range amp, the amp will most likely offer High, and low, and subwoofer crossover adjustments.
• Low Pass Filter @24dB Slope : 35~250Hz
Bass boost in this case at 45 hertz, is nothing more than a built in EQ at that frequency point. In this case, the amp allows you to raise the effective volume by adding 9db of gain to the output.
• Bass Boost @ 45Hz : 0~9 dB
Subsonic filters are one of the most misunderstood specs on an amp. Obviously all subwoofers are not created equal. All play bass, but some do it better than others. Some are built to handle large amounts of peak power, and others are not. A subsonic filter is a high pass crossover for subwoofers, The lower you go in frequency, the longer the sound wave, and the more the speaker cone will move and depending on the speaker you purchase excess movement can damage the speaker, spider, or voice coil. The subsonic filter allows you to add a high pass crossover to the subwoofer to prevent it from playing too low.
• Subsonic Filter @24dB Slope : 10~50Hz
Phase shift is another misunderstood concept. Sound waves are either in phase with normal waves or out of phase by a certain amount of degrees. When you install speakers in cars, the phase of the speakers can change just by their location. This adjustment will allow you to make modifications to the phase of the wave output to bring your speaker more in line with the rest of the system. You might ask how in the world could you do that with your ears alone. So first an example of what your doing when you adjust the phase. If you took two identical speakers and sat them on the floor, and wires one of them in reverse, They would cancel each other out and the bass would be minimum. When your listening in the car and adjusting, the bass location will appear to move from the back of the car to the front of the car the more you go out of phase, because you are in affect changing the localization effect of the sound wave.
• Phase Shift : 0~180
This amp has the ability to act as a master with additional slave amps connected to it, so you could control all of the amps from one.
• Degree's Master/Slave (Strappable) : Yes
It is what it say it is, this is a remote bass knob that allows you to adjust the gain control of the bass boost remotely.
• Remote Level Control (Bass Knob)
And lastly, very importantly the input size of the wire the amp will allow. Do's. Use the largest wire the amp will take. Use the same size wire you used for power or larger wire for ground. Dont's DO NOT TRY TO POWER THE AMP FROM YOUR FUSE BOX. Make sure you install a fuse at least of the maximum amount the amp will draw installed at least no more than 18" from the battery and 18" from the amp. The fuses in the amp protect the amp circuit. If their is a short in the power line, The fuses in the amp will not save your amp from being fried.
• Power & Ground Input : 4 Gauge
• Dimensions (mm) : 250L x 241W x 64.5H
