Some questions concerning car audio systems (Equipment, RMS, OHMS) Help!?
I want to go out and purchase a car audio system next week and want to find out what to look for.
So firstly, what is RMS and is more better or less better?
Secondly, Is more ohms better or less better?
Thirdly, im looking to buy 1 or 2 subs (Not sure yet), an amplifier, a deck, and 6 by 9’s x2 (Putting it above the boot behind the back seat head rests). Is that what i need for a car audio system? am i missing anything i NEED?
RMS Power vs. Peak Pcontinuousamount of conthat’sus power, measured in watts, that an amplifier produces is called RMS power. The higher the RMS figure, the louder and cleaner your music sounds. When choosing an amplifier, the RMS rating is the power rating you should pay most attention to.
Ohms- impedance (resistance)–
Impedance
Impedance is a measure of the resistance of a speaker’s voice coil to the audio current supplied by the amplifier.
Impedance
The total opposition to the flow of alternating current in an electrical circuit at a given frequency. Impedance is measured in Ohms. Although car audio manufacturers label the impedance of most car speakers and subs at 4-ohms, the impedance of a speaker is actually not a constant. It’s actual impedance changes with frequency and can vary greatly. Therefore, though 4-ohms is the standard impedance in car audio, this standard is more of an average impedance for speakers and amplifiers when driven within the part of the audio spectrum for which they are designed.
Ohm
The unit of measurement for impedance or resistance. It tells you how much a device will resist the flow of current. If you take two signals of exactly the same strength and send one to a 4-ohm speaker and the other to an 8-ohm speaker, twice as much current will flow through the 4-ohm speaker. In other words, the 8-ohm speaker will require twice as much power (wattage) to play at the same volume.
Resistance
The opposition to the flow of electrical current. Resistance is measured in Ohms.
—the lower the final impedance at the amp the lower the sound quality, but the easier/cheaper it is to power
(this link will help you pick the correct sub setup for your desired final impedance at the amp http://www.the12volt.com/caraudio/woofer_configurations.asp)
—the more cone surface area you have the louder it will be, so 2 subs is better than one
when it comes to car audio nine times out of ten you get what you pay for- and you need to look for CEA-compliant brands which means that the amps have been tested and produce or exceed the advertised RMS wattage with minimum distortion and the subs can handle their advertised RMS wattage also (distortion is the main cause of speaker damage over time)
here are the top CEA-compliant brands
Alpine (highly recommend)
Bazooka (don’t like their subs)
Blaupunkt (don’t like their subs)
Clarion
Eclipse
Infinity (highly recommend)
JBL
JL Audio (very good but over priced)
JVC
Kenwood (don’t like their subs)
Kicker (the best in my opinion)
MTX (highly recommend)
Pioneer
Polk Audio (highly recommend)
PPI
Rockford Fosgate (highly recommend)
Sony (don’t like their subs)
March 8th, 2010 at 10:45 pm
This my be lengthy,
RMS stands for root mean square. I don’t know all the details but whatever the rms wattage is, the true and continuous wattage. So for example: say a pioneer 6×9 speaker has a peak power of 300 watts (300 watts is advertised on the box) but its rms power handling is only 40 watts. Well, that means that you want to have an amp that will send around 40 watts rms to the speaker. The same goes for amps. Say a 1800 watt amp only sends 300 watts rms, well 300 watts is how much that amp is gonna push. I know it is stupid that companies get away with advertising peak power and it’s usually nothing more than a marketing ploy to trick naive consumers.
-First thing: Head Unit (deck, cd player). I would stick with 2 brands: Alpine or Eclipse. These units are great and sound great. Pioneer and Kenwood are good but in my opinion Alpine and or Eclipse are at the top. Find the feat. u like. (aux inputs, ipod input, mp3, wma, gps, eq’s etc). I suggest to get one with 3 sets of rca preouts with at least 4volts or higher. These are the rca outputs that send the signal to your amplifiers. Audition different head units and find one that you like.
Ohms or impedance is the resistance in the electrical current of your wires. Usually the lower the ohms or resistance the more power that can be sent to the speaker. To choose a subwoofer or woofers, you have to also know what kind of amp to match them with.
Crutchfield has a great wiring diagram that will help you understand:
http://www.crutchfield.com/S-5nXyoTIH3DJ/learn/learningcenter/car/subwoofers_wiring.html
Read that and look at different choices. Remember most amps have a certain ohm level that they run stable at. The lower the resistance the more unstable some amps will become.
For 6×9’s, just buy some name brand speakers like, Alpine, Pioneer, Focal, MB Quart etc. You will probably want to amp them since their power handling will be higher than the amount of power your deck puts out, or else you won’t get to be real loud without distortion.
Buy some good wires and sub box.
Do a lot of research and shopping. The more time you spend picking a product the happier you will be in the long run. I learned that the hard way.
Good luck Hoped this helped.
References :
March 8th, 2010 at 11:02 pm
RMS Power vs. Peak Pcontinuousamount of conthat’sus power, measured in watts, that an amplifier produces is called RMS power. The higher the RMS figure, the louder and cleaner your music sounds. When choosing an amplifier, the RMS rating is the power rating you should pay most attention to.
Ohms- impedance (resistance)–
Impedance
Impedance is a measure of the resistance of a speaker’s voice coil to the audio current supplied by the amplifier.
Impedance
The total opposition to the flow of alternating current in an electrical circuit at a given frequency. Impedance is measured in Ohms. Although car audio manufacturers label the impedance of most car speakers and subs at 4-ohms, the impedance of a speaker is actually not a constant. It’s actual impedance changes with frequency and can vary greatly. Therefore, though 4-ohms is the standard impedance in car audio, this standard is more of an average impedance for speakers and amplifiers when driven within the part of the audio spectrum for which they are designed.
Ohm
The unit of measurement for impedance or resistance. It tells you how much a device will resist the flow of current. If you take two signals of exactly the same strength and send one to a 4-ohm speaker and the other to an 8-ohm speaker, twice as much current will flow through the 4-ohm speaker. In other words, the 8-ohm speaker will require twice as much power (wattage) to play at the same volume.
Resistance
The opposition to the flow of electrical current. Resistance is measured in Ohms.
—the lower the final impedance at the amp the lower the sound quality, but the easier/cheaper it is to power
(this link will help you pick the correct sub setup for your desired final impedance at the amp http://www.the12volt.com/caraudio/woofer_configurations.asp)
—the more cone surface area you have the louder it will be, so 2 subs is better than one
when it comes to car audio nine times out of ten you get what you pay for- and you need to look for CEA-compliant brands which means that the amps have been tested and produce or exceed the advertised RMS wattage with minimum distortion and the subs can handle their advertised RMS wattage also (distortion is the main cause of speaker damage over time)
here are the top CEA-compliant brands
Alpine (highly recommend)
Bazooka (don’t like their subs)
Blaupunkt (don’t like their subs)
Clarion
Eclipse
Infinity (highly recommend)
JBL
JL Audio (very good but over priced)
JVC
Kenwood (don’t like their subs)
Kicker (the best in my opinion)
MTX (highly recommend)
Pioneer
Polk Audio (highly recommend)
PPI
Rockford Fosgate (highly recommend)
Sony (don’t like their subs)
References :