[Rolis]

hey wats the difference between subwoofer mono amp, multi-channel amp, and 2 channel amps

[ChrisJ]

Heres A Good Read

Originally Posted by www.caraudiohelp.com Car Audio Amplifiers The purpose of a car audio amplifier is to take a low level signal from the source unit and change it into a high level signal for driving the loudspeakers. Amplifiers range in power from about twenty watts per channel to over one thousand watts per channel. The price range can be anywhere from fifty dollars to several thousand dollars depending on features, power output and quality. An amplifier may have as little as one channel of output to as many as eight channels at the time of this writing. The most common amplifiers are two and four channel models although mono subwoofer amplifiers are gaining in popularity. Amplifier Power Ratings Extra features may also be built into a power amplifier. These features include built-in active crossovers, equalizers, signal processing and speaker level inputs. When shopping for an amplifier consider that all power ratings are not created equal. Some of the low-quality brands will exaggerate or even outright lie about the power output of their amplifiers. This is a good reason to stick with the well known manufacturers. The only true measure of an amplifier's power is its continuous power rating or R.M.S. rating. R.M.S. is an acronym for root mean square and refers to the amplifiers average power output. Car Amplifier Quality Also keep in mind the quality of the amplifier. A generally good indication of quality build and the power output is the size and the weight of the amplifier itself. Better quality amplifiers will usually have a heavier and larger heatsink versus a low quality amplifier of the same power rating. Do not accept size as a definite indication though. I bought an amplifier at a yard sale for two dollars that was two feet long, eight inches wide and two inches tall that had a five inch square circuit board inside of it. This amplifier was so poorly built that I could actually hear the music I was playing coming from the circuit board itself. However there are many top quality amplifiers that do not follow this rule. For example, Blaupunkt makes a line of amplifiers that have a plastic shell. Because of the high efficiency design of those amplifiers a heavy heatsink is not required. Also a good indication of an amplifier's true output is the size of the fuse used. True two hundred watt amplifiers do not use a ten amp fuse. Use your head when buying and keep in mind the brand's reputation for quality. If you find yourself on a budget or lack space for many components then the economical thing to do is buy a multi-channel amplifier with the built in features and processors that you desire. This can save a lot of room and several hundred dollars in added component and installation cost. The quality will be a little less as compared to outboard processors but will probably not be noticed. Also, by minimizing the number of components the chance of noise entering into the system is lessened. Some features and aspects of amplifiers to consider are: Bridgeable: This feature allows a pair of amplifier power channels to be combined into one channel of greater power. This is usually used for driving a subwoofer although it will work with any other type of speaker as well Channels: The more channels an amplifier has the greater the installation flexibility it will have. Especially in terms of options, future add-ons and upgrades. Class: This refers to the way the amplifier operates. The three types that are most likely to be encountered are A, A/B, and D. Class A amplifiers are the least efficient in terms of power consumption, staying on continually, but also have better sound in general than A/B amplifiers. They are very rare in car audio. Class A/B amplifiers are more efficient than the class A design and are the most common type. Almost all amplifiers in the car audio market are of the A/B design. Class D amplifiers are usually reserved for high power subwoofer amplifiers and can reach efficiencies in the 80%+ range. This design can therefore be smaller, uses less current and produces less heat than the other classes. Connectors: This is the method of attachment used for wires that are connected to the amplifier, including speaker and power wires. The most common kind is the screw terminal strip. This is a series of screw connectors that can be removed and replaced without compromising the amplifier. The other main type of attachment is the "Molex" type connector. This method involves a wire harness that plugs into the amplifier after the power and speaker connections have been made with a crimp or solder connection. If the amplifier is installed in more than one system these wires can get pretty short over time and become more difficult and even dangerous to work with. A variation on the two is a harness that the power and speaker wires screw into. Then the harness plugs into the amplifier. This is probably the most convenient of all connections. Crossover/Filter: A built in crossover can be useful, especially if it is many frequencies of adjustment. A filter is a crossover that only affects one channel, not actually splitting frequencies but simply reducing a range of them. Distortion: This is often given as T.H.D. or total harmonic distortion. It is the measure of how much an amplifier will change a signal from the input signal it is given. Figures below 0.1% are negligible and will not be heard. Usually the figure can be in the 3% range without being heard but virtually all high quality amplifiers will have a T.H.D. below 0.1%. Efficiency: This is the ratio of of power input (from the battery) to power output (to the speakers). A 100 watt amplifier with an efficiency of 50% would take in 200 watts of power from the battery and output 100 watts of power to the speakers. The other 100 watts of power would be wasted as heat. The higher the efficiency of an amplifier the better. Power Output: The rated power output of an amplifier should be given into a four ohm load, all channels driven from twenty to twenty thousand hertz (20Hz-20kHz). Keep in mind that while the low end amplifiers are exaggerated in their power output, many high end amplifiers are under-rated in their power output. These are sometimes called "cheater amps" because they allow a car audio competitor to compete in a lower power class while in reality having a larger amplifier. This under-rating can be three times less than the actual power output. Power Supply: The two most common types are the IC chip and the MOSFET supply. The IC chip is what is used in most source units (head units) and are only capable of producing about twenty watts per channel. MOSFET is the more common design and has a smoother sound than the chip design. Pre-amp Inputs: This is a set of jacks (usually RCA jacks) that will accept a low level pre-amp signal from a source or processing unit. Pre-amp Outputs: This is a set of jacks (usually RCA jacks) that pass on a low level pre-amp signal to another amplifier or processing unit. These will sometimes be filtered outputs. Separate Gain Controls: This allows the gain of each channel of the amplifier to be set independently of the other(s). Speaker Level Inputs: For source units that do not have pre-amp level RCA outputs this feature may be used to take the signal from the speaker leads of the source unit. The signal will not be as clean as a pre-amp level output but will be adequate for most factory upgrade applications. Stability: The measure of how low of an impedance load an amplifier can handle (in ohms). Any good quality amplifier will be two ohm stable while a rare few will go as low as a quarter of an ohm. Ideally an amplifier should double its power each time the load is halved. For example, a one hundred watt amplifier (into a four ohm load) should produce two hundred watts into a two ohm load and so on. This is most useful when running multiple speakers off of a single amplifier or in sound off competitions that are classed by total power output. Tri-Mode Output: This feature is available under different names but is the ability of an amplifier to run a stereo pair of speakers and a mono subwoofer (or center channel) from only two channels of the amplifier. Personally, I would not recommend doing this. Instead buy a good quality four channel amplifier and bridge two of the channels for the subwoofer. Tube Amplifiers: These are the least common amplifiers and are also the most expensive. Rather than the traditional solid state components they use old fashioned vacuum tubes. They are said to produce a warmer sound and a smoother midrange than solid state designs. For most systems the standard design will be more desirable.

Above Article

These are some good reads and I think will help you out alot...

[Rolis]

thats a long read but it sure helped out alot i was thinkin of going with all kicker stuff like speakers subs amp tweeters so i just wanted to know wat would be a better amp outa the three amps they have and i think from wat u put the multi-channel amp would be best i just dont know which one of them is the best

[97TunedMustang]

That may still of been kind of confusing for you i would have to guess so i'll try to help you sort some things out. If your planning on getting subwoofers your not gonna want to use just a multi channel amp. Those amps are good for your components speakers in the cabin, their not designed to be running subwoofers. Now whether you go with a 2 channel amp or Monoblock type amplifier depends on what subs your going to get to go with them. If you want to keep both left and right channels for your subs go with the two channel and also if you dont need more then about 400rms of power, because thats about as big as they come. Really two channels for subs are pretty pointless because your subwoofers produce bass which is omnidirectional and you cant tell where its coming from anyway which is why its not any better to have them in the front by you, then in the trunk behind you. Anyways, if your wanting to go with more power somewhere between 800rms and 2000rms wattage your going to want a class D 1ohm stable mono block single channel amplifier. You can use one or two or however many subwoofers with these amps, you just have to change the wiring to the subwoofers to keep the ohm load within the amps operating limits. Here is a site to calculate this. http://www.crutchfieldadvisor.com/IS...rs_wiring.html

For example if you have two subs that are dual 4 ohm voice coils and a 1ohm stable amp you would wire them in parallel like so.


another example of a 2 subwoofer setup wired in series on a 2ohm stable amp...


Their is also more then one way to setup a single, pair, or triplet of subs on any amplifier. you simply have to use ohms law (or that site, lol) to make sure your not exceeding the amplifiers capabilities. you can always go higher on the ohms just not lower then rated. a 1ohm stable amp will run 2ohm stable, and also 4ohm stable. The higher the ohm rating the less the power the amp will be pushing to the sub or subs. So you want to wire them optimally with the lowest ohms possible that the amp can handle. This is why its important to buy the right subs for your amp. Whether they are Single Voice Coil (SVC) or Dual Voice Coil (DVC , 2 coils per sub) to get the most out of your audio setup. Heres some info on the output rating for a..

Hifonics Brutus Bxi1206D Class D Mono Block Amplfier.
1 ohm: 1200 watts x 1 channel
2 ohms: 900 watts x 1 channel
4 ohms: 450 watts x 1 channel

This shows you how power output is affected by different wiring scenarios.These are continuous RMS wattage ratings i should point out. not peak ratings like most of the crap best buy sells. RMS is what your going to see that amp pushing on a continuous base versus peak which the amp will rarely ever hit. If you see a Sony 1200 watt amp. its 1200 peak wattage. Its only 500rms bridged continuous power so dont let that confuse you. Always look for the RMS power output of amplfiers your looking at to match to your subs. You will also want to look at the subs RMS wattage handling ability.