4 inch car speakers

What Do I Need To Know About Purchasing A Car Audio System ...

-Im sure you know what a cd player is(j/k) but if you ever want to replace a stock cd player then you are going to by what is called an aftermarket cd player or cd Deck. It comes with bells and whistles. Some of these bells and whistles include face plates. A Detachable face plate allows you to remove the fron of the cd player aka the face plate(the thing that has all the buttons on it) and put it in a safe place so it wont get stolen if youre car is ever broken into. When getting a cd player make sure they have pre-amp outs. This will mean that they have an output avalability so that you can hook up a amp and sub( you only need 2 pre amp outs but i would reccomend 4 so that you can expand as much as you want) —- If you want to replace your car speakers so that your high frequency( the frequency that produces the music instrument and the words of the songs….not the bass part even though it produces some amount of bass) will be louder then this are what you want to look for: Look to see what the cone is made out of. A polypropylene cone is what you will want. polypropylene cones are made out of a hard material that is less likely to be bent out of shape when turned up really loud. You could check Crutchfield.com to see what size speakers you need to replace the ones you have. The amp and subwoofer combines to produce the bass and the thump in the trunk. Things to look for: The wattage is the first thing you want to look for but do not go by Max Watts but instead go by RMS Wattage(This is the most important thing you want to look for). The closer the RMS wattage of the amp is to the RMS of the subwoofer the better you are. i.e. a 400 watt rms 800 watt max amp to a 375 watt rms 600 watt max subwoofer would be perfect. Amps have what is called channels that distribute watts to the subwoofers. The more channels the more subwoofers you can hook up but it is possible to hook up 2 subwoofers to an amp with only 1 channel aka a mono block amp. You would twist the wires together (making sure you twist 2 positives together and 2 negatives together) and plug it into the amp. Make sure the rms is still in consideration. for example A 750 watt Rms 1000 watt maxx with 1 channel can be paired with 2 subwoofers with 400 watt rms and 800 watts maxx(That is each subwoofer having 400 watt rms combining to produce up to 800 rms in total). This is done alot. 1. Power. I know, this is where MOST people look first, but it’s the very reason you are buying an amp, right? Also knowing Ohm’s Law, and knowing that I will almost always load an amplifier with the maximum specified impedance (impedance - 4 ohms or higher, NOT load - 4 ohms or lower), I need to know exactly how much power I am looking at to start with. When loading an amp with a higher impedance, the amp will make less power, so I have to keep this spec in mind the whole time. My speakers are almost always chosen before I decide to start looking for an amplifier, I know the impedance and efficiency numbers when I start. This will help me decide how much power I need or want for that particular driver compliment. I will NEVER look at “Max Ratings”. They are often worthless, generally overinflated, selling tools, designed by old-school, low-end amplifier companies, originally made to sell product. (You remember how it went (and still goes today)… This 800 watt amplifier is only 200 dollars, but the Nakamichi 160 watt monoblock is 1300 bux for the pair. Which were (are) YOU going to buy?) Ahhhh, the power of advertising… Classic Nakamichi, Alpine, Linear Power, Orion, Eclipse, etc., THEY never posted “Maximum Power” numbers, did they? Unfortunately, even the good products of today will state maximum power output, I just disregard the numbers posted. 2. Signal to noise ratio. This one I place a bit more weight on, especially when the amplifier is going to be used in a mid-bass (important), mid-range (more important) or highs (MOST important) application. The higher the better, and there is no exception to this rule for me. Amps with tube stages are typically less capable than their solid state stablemates in this area, but I do make exceptions for tube amps. It is NOT a terribly important spec for a bass amp, so when shopping for a bass amp, don’t bother with this number. Dedicated bass amps, BTW, usually offer awful SNR numbers. 3. Efficiency. Here’s where you will be able to tell a decent manufacturer from the crap. Let’s say you are looking at an 250 watt (RMS) amplifier. The first physical thing I look at, is how big a fuse do they recommend (or what size fuse is in the end of the amp)? I know right now that 250 watts OUT will demand (and I use 50% efficiency to keep it simple) 500 watts in. 500 watts in, divided by the (car running) battery voltage (14.4v) is about 35A. If I look at the end of the amp, and see a 20A fuse, I’m walking away, as there is no way that amp can make 250 REAL watts, continuously. 14.4v times 20A, equals 280 watts in. 250 watts out, divided by 280 watts in, translates to an 89% efficiency. In a class A/B amp, this is an impossible number, and it even stretches the imagination for digital amps, as well. The theoretical MAXIMUM efficiency for class A/B is 66%, (95% for digital) so someone is lying. I don’t care WHO the manufacturer is, if these numbers don’t add up, I will start looking elsewhere… Now, if all the other specification look good, AND I can get in the vicinity of the RMS power I am looking for, I will buy an amp that’s efficiency number might be stretching the truth a bit. My old Nak 160 watt monoblocks had 40A (that’s 480 watts in - a 33% efficiency, people!) fuses in each one, and they ran hotter than a firecracker, even loaded at over 8 ohms. I liked that. 4. Terminals. A frequently overlooked part of an amp, this is a very important part of an amp to me. A car is a place frought with vibrations. A cheap or cheezy feeling connector in power or speaker terminals and most ESPECIALLY in the RCA inputs, will often cause problems in the future. Setscrews for power, quality terminal blocks for speaker outputs, and Tiffany style RCA connections (the type attached to the chassis, rather than a block of plastic soldered to the PC board.) The quality of the I/Os can be a direct indicator of the attention to detail paid to the rest of the piece. Translation? Overall Quality. 6. Damping Factor. I used to place more emphasis on this spec, but my research recently (over the last few years, really) has, while not proven to me it is a useless spec, has not proven to me it is an extremely important spec. This is why this particular spec is a little further down the list. While I place a bit more emphasis on it for a bass or mid-bass amp, I, admittedly, place less weight here than I used to… These are the things I look for when trying to decide on an amp. OBVIOUSLY, there are going to be VERY few amps on the market that will make me happy across the board, but then some of the physical characteristics listed above can be made to fit me and my desires with a little time, a couple extra bux, and some careful use of a soldering iron

Source: What Do I Need To Know About Purchasing A Car Audio System ...