WARNING: Those with ADD will need to read this one section at a time. It’s a big 'un. This is a VERY long post, I’m telling you this now. You thought the others were big No no, this will be the daddy of all posts to date.
So you decided to do some upgrading or starting from scratch? This is no problem. This will provide you with some info on how to pick out equipment for your ride. I will go over some tips on how to pick out all parts of a full system, but you don’t always have to go all out and spend a ton of money. Use the parts of this post that you need. The term “system” is used very loosely by a lot of people with little consistency. I feel that a system should consist of (aftermarket parts of course, stock doesn’t count) a headunit, speakers, a sub and an amp for that sub, at least. More complex sound systems will include things like more amplifiers for speakers, cross overs, sound processors, DVD players and all kinds of other items you can hook up. A core system should cover the basics of upgrades. A source of sound (headunit) and what produces the sound (speakers and a sub/subs).
Headunints
Personally I feel that the headunit (deck, CD player, whatever you want to call it) is the single most important component of a properly built audio system. The basic point behind that is that if you don’t have a good headunit producing a quality signal you’re not getting proper sound and your speakers wont matter. Now, I’m not saying that you have to go ahead and buy top of the line equipment. No, you should really get what suits your needs. I find it’s a good idea to get something slightly better than what you need vs almost there. It’s really worth it in the long run. There are numerous manufacturers that offer a variety of lines of headunits. It can get a bit confusing at times. I usually say this in regards to audio equipment, but let me reiterate once more. Looks should never really be a concern when picking out parts for your system, unless you’re going show only. I want to make it very clear that all those pieces that are shiny, or glow or do anything that doesn’t have to do with sound will be money wasted unless you have a show only car. They also do absolutely nothing function-wise. I have seen speakers with lights inserted in the actual speaker, that’s right, lights! It only looks neat when it’s dark. You don’t really see the speaker move, you only see some light trails. In general it is NOT a good idea to poke holes in your speakers. :nono :nono :nono I mean, would you want to drill some holes in your block or poke some in your tires before driving? When you decide to get yourself some audio upgrades, this doesn’t mean you HAVE TO get everything at once. Yes, it’s easier because you will have to do only one install, but most people have constrictions such as budget or time. I won’t be going over manufacturer names in this post because of two reasons. I don’t want to seem biased towards something (and I really think I am) and I’m not getting paid to advertise for them. I will leave the choice up to you. When you start your build, you should always start with picking out a headunit. Don’t just think of the first manufacturer that comes to mind and grab one off a shelf. This will get you close to nowhere. Write out a list of features you want to have and find a bunch of headunits that have that. Remember, you won’t always get everything you want and you will need to make some compromises or increase your budget. I’ll go over a few features that you should keep in mind when picking out the headunit. RMS voltage on the outputs is important because the higher it is, the cleaner your signal will be. When you’re looking at the list of features make sure the voltage or wattage it states is Peak or RMS. There is a good difference between the two. RMS is continuous and the headunit will hold that much voltage throughout. Peak is only for a tiny bit of time and then it drops off. 8v RMS is extremely nice (I have it on my headunit) but even if it can hold 5v it will sound very nice. Another great feature (pretty often overlooked) is the crossover. This part is pretty technical, but know this- wider range is better. If you’re not going with a signal processor (like an equalizer) you should get a headunit with the best possible crossover and equalizer built in. This helps ensure your sound is balanced and the proper frequencies go to their respective drivers (or speakers). Some people also pick out a headunit based on if it has buttons or knobs. This is NOT the correct way of choosing your equipment unless you’re going with two high end pieces and they both have the same features. Usually I prefer buttons, but the one I’ve got now uses knobs for volume and track switching. It took a bit of time to get used to using knobs and their sensitivity, but now it’s fine. Remember that there really isn’t an end-all headunit, most manufacturers release a new model one a year or in two years. Sometimes it’s a good idea to buy a brand new unit from last year shortly after the most recent model hit the shelves. This means good news for you, because you’re getting a nice piece of equipment at a reduced price. There are some manufacturers that are mainstream and produce a wide gamut of headunits for all budgets and there are some that just make expensive pieces. Don’t be scared to at least try some of the more expensive ones, you might find yourself getting one and loving every minute of it. A good way to pick one out is to go to stores and just using them in the display boards. Try to get into the menu, or change a simple setting to see how easy the interface is. Go online and read some customer reviews about some headunits you’ve got your eye on. Another way to get additional info is to find people (locally is best) that already own one and talk to them. Ask them what they like and dislike about that particular model, what they would change and such. If all this seems a bit much for just a headunit, remember that this is basically the brain of your system and it should really be the single best piece you own if you’re on a tight budget. A cheap set of speakers with a great headunit sounds better than a cheap headunit with great speakers. There is also a very simple way or picking out a headunit. You set a budget of X dollars and find one that has the most for the dollar. This ensures you stick to a set price, but it doesn’t mean it’s something that will work for what you need or want. You should also keep in mind the fact that expansion is possible. Some people thing you just get the one headunit and it works with everything you’ve got for it. It’s not always the case, so don’t just hope for it to kind of work out. You need to make sure that it has additional outputs and possibly inputs for future upgrades if you plan to add more components(such as amplifiers or complex sound processors). If you don’t plan to use a subwoofer, you can get a rather simple and cheap headunit for just the speakers, but most of those don’t sound as clean as they could. Ones that come with additional outputs tend to have better internal components so the output is better and cleaner. If you are building a simple setup then you will need to get one with a subwoofer output. When picking one out, make sure it has a function in the menu where you can adjust that subwoofer individually and not just by increasing or decreasing overall bass (I speak from experience on this one). Sometimes you might get a headache and don’t want that bass pounding, but you want the rest of the music playing normally, so it will come in handy. It’s also a great feature for tuning. Most headunits nowadays will play burned cd’s. You can also go for one that plays mp3’s as this will give you more music per cd so you don’t have to bring that 50 page cd binder. On average a single mp3 disc fits 10-12 normal cd’s. If you don’t plan to get an amplifier at some point for your speakers, find a headunit with good RMS output. Don’t look at the peak or total output, worry about RMS output per channel (per speaker). The higher it is the better. This doesn’t mean it will be insanely loud, but it will help ensure higher quality of sound. Keep in mind that when I say “higher quality sound” I don’t mean something like what I’m building. Most of you will never need a setup like mine, its overkill for an average consumer. What I mean is that it will sound better than stock and better in general.
Speakers
One other important aspect of a nicely rounded system is its speakers. There are even more speaker choices than headunits so this can get pretty scary for most people. If you were to add all the manufacturer’s lines of speakers it’d make your head spin. This really isn’t scary at all. What most of you will need to do is find out the factory speaker dimensions. You will be using those numbers to make sure your new set fits. There are ways to get a different size, but it requires more work, materials and obviously some more money. How much money? Well it all depends on what you end up doing. If you pick something that would never normally fit in your doors, you’ll be looking at a good amount of cash before they’re in and working for you. For the most part sticking to OEM sizes is good. I prefer to fit the largest speaker I can, but it’s not always easy or cheap. There are a few different types of speakers, so I will be covering just a few of the common ones you’ll find. The best type is called a component set. This comes with 2 tweeters (tiny 1 inch speakers made to produce only high pitched sounds), mid range drivers (these play mid range sounds best) and a set of passive crossovers (these ensure the speakers and tweeter get their proper range of sound to reproduce). Most passive crossovers are generally the same, but there are ones that can go upwards of 200 dollars per crossover. Most of you will not need to go that high up the ladder. There are also coaxial speakers. This kind has the tweeter affixed someplace on the speaker. A lot of the times they sit right in the middle. These are okay sounding (and are usually cheaper than components), but they are not great. They do not have crossovers and they tend to get muddy at higher volumes. Loud isn’t everything to sound. Speakers are almost the same as headunits. Manufacturers often make new ones every year or two so keep that in mind. The best way to pick out a set is to hear them. You can look at their technical data and specs but it won’t give you a full picture about them, so to speak. A good way to compare them is to go to a shop and ask them to play one of your cd’s that you’re familiar with. Pick out something you’ve heard a lot of times and basically know all the notes and how they should sound. Have them use just the headunit and no amplifiers. Play a track on one set of speakers, and then play the same one on a different set of speakers keeping all the settings the same. Listen for differences. You will most likely how the more expensive ones sound, so just check out ones you can get. Go around to a bunch of shops and check out as many as you can so you’ve got a great baseline of comparison. There will be a set or two that stood out the most and that’s the ones you should concentrate on. When picking speakers don’t have a single number for a price, have a range and pick ones that fit that. More expensive doesn’t always mean better. You should really just listen and go with ones that sound best to your own ears. Don’t just grab onto a set because the name is popular. Buy the best ones you can afford to buy. You don’t have to buy them with the headunit. You can piece together a very nice system one part at a time. You can go to the Kill The Buzz thread to get some tips on how to make speakers sound better if you don’t buy something top of the line. Any speaker will sound better if you work with it a little bit. Personally I prefer titanium (vs silk or ceramic) tweeters, but most people find them a bit harsh. You don’t have to go that high end, but if you can, it’s great. As far as mid drivers, try to go with a 6 inch or more in diameter, especially if you plan to get an amplifier for those. 6 inches is where really nice mids start to appear. I’ve always had 6.5 inch speakers and they have always sounded amazing. As with the rest of the components of a system, I pay no attention to looks. For example, my previous speakers looked like a cheap 25 dollar Wall Mart set, but got me trophies. One other good way to pick out speakers is to show up to a sound competition. You will find a good variety of equipment that you could listen to and compare. Keep in mind, that base line of comparison you had at a shop doesn’t apply here. Everyone has different cars and equipment, so they WILL sound different, but you will notice some similarities. Some speakers will have a nicer mid or very bright highs. There are really too many variables to keep in mind, but it’s a great way to see what people use. Ask them what they’ve had before and why they switched. If you find a person that just showed up in a show, put down a credit card and said “I want a system”, walk away. They won’t tell you anything useful. You need to find people that have built their own setups. Those are the ones that know all about it and will give you the most useful advice. If you go to an SQ competition you can also ask the judges for some tips on building a setup. Most of the time they will give you some very good advice that you should stick to. See if you can catch the 1st and 2nd place trophy winners for a small chat about their setup. I usually do a nice walkabout and see who’s got what and have a little chat with the car owners about why they did what they did and why they are using the equipment and such. I ask them about the highs and the lows of that particular setup and see if they’d want to change something to make it better.
Crossovers
Passive (non powered) crossovers are very useful if you are not going to use an external equalizer or a signal processor. These are very easy to use and you can mount them virtually anywhere. Today manufacturers try to make them look more appealing so you can mount them somewhere where people can see them if you want some more attention to the car. It’s not complex to wire crossovers either, so most people will be fine with the instructions they come with. Like I was saying before, there are ones that are pretty plain and ones that are as complex as it gets. Grab the ones that come with the speakers. Use the best ones you can afford. In general it makes no difference what they look like, so most people will put them in the doors. When you do that, make sure they’re out of the way of moving parts and are protected from the water droplets that can get on them during rain. The safest place is somewhere inside the car. If you purchase speakers and they come with crossovers you should definitely use them. They also sell powered ones and if you can afford to, you go with that set. Those will help out with restoring some signal loss and some even add a little bit more voltage to the signal. This kind gives you a more precise degree of control over sound output you will get from your speakers.
External Equalizers
These can be useful to any system. You can find these pretty cheap and almost anywhere they sell electronics. This is a good idea to use if the built in equalizer in the headunit isn’t enough. Basically the more bands it offers the more control you have over sound. The point of an equalizer is not to push all those sliders or turn all the knobs to max. Every car has a difference resonance and distortion properties. Cars will eat some frequencies more than others and this is what the equalizer helps correct for. You want a nice balance across the whole spectrum of sound. I will cover tuning more in depth further. In general all equalizers are the same if you don’t go high end. You should go with a dependable company with this one. There really isn’t much you can do as far as listening to them. Read reviews and ask people that have one. A typical one should be between 5-8 bands. Get at least 5, because the ones that are built into headunits only have “high, mid and low” on them and its basically useless. If you don’t have any experience tuning or don’t have a musical ear, leave this to somebody that knows how to do it right. Generally the equalizers are small and pretty slim so they fit well under or just above the headunit in your car. You don’t want to put it in your trunk or hide it under panels as you’ll be needing to adjust it as you tune the car, plus you don’t want miles of extra wires all over.
Sound Processors
These things are absolutely great for a very high degree of control over your sound. Most people wont need one, but if you can get one, it will be a great addition to your system. These run a full gamut from doing everything to very simple dinky little units. These will allow you to get 5.1 surround sound (provided you’ve got the equipment) just like in the movies. These can take care of the equalizer, line driver, cross over, time delay and etc functions for you guys that want to go high end. These are much better that a simple equalizer as they have a lot more bands, a wider range crossover and so on. If you’re getting a sound processor then you shouldn’t use anything else. This will take care of most of the duties and this is the piece that will need the most work during tuning. This will require more money, time and patience, but to me its worth having one in my car. The one I have doesn’t require me sitting on top of it turning knobs or pushing buttons. You can use a laptop or a PDA and tune it via BlueTooth. If you want to pick out a sound processor you should definitely talk to people that work in stereo shops or people that own them. It’s also a good idea to get the newest top of the line processor. This is important because they always add more features and use better components each time they make a new one, so it’s worth going with the newest and best and not just any kind you can find.
Subwoofer
This is the part of your system that will take care of you bass needs. Don’t expect to hear anything but low tones out of these and don’t try to make them play anything else as you may damage the speaker. Subwoofers range from 8 inches and upwards for 2-3 feet in diameter. Most people use 10 or 12 inch ones. Anything over 15 is just for show and is overkill or for a MASSIVE PA system. Getting two or three doesn’t mean it will sound better or much louder. Only way to really make it louder is to double the power to gain about 2-3 decibels. Loud isn’t always good, as it will cover other frequencies and all you’ll head is just the bass going BOMMM BOMM BOMM. A key feature of a system is balance. You don’t want anything to overpower anything else. Everything will need to sound equal, so your highs, mids and lows all come through clearly. You should pick out subwoofers just like I described for speakers. Listen to the same track on the same set of speakers using different subwoofers. Find the one that sounds the cleanest and smoothest. As far as picking out the size goes you need to keep some things in mind. Bigger isn’t always better. The big speakers don’t sound as clean as the smaller ones and don’t respond as fast because the speaker cone is big and heavy. You should pick what works for your vehicle. If it’s a small car, a single 10 will work find. For a large sedan 2 10s, 1 or 2 12s will work out just fine. SUV’s and vans have more air inside to move around so they will need 2 12s or maybe even 15s. Just because 3 10s looks cool in that plexi window with the lights it doesn’t mean you need to get that. It may look nice, but you’re not going to get as best sound as you would with something appropriate for your car. If you’re going for purely show, then cram that trunk full of 10s and slap on lights all over the place. It will sound like crud, but damn will it look nice. Some subwoofers are built for SPL and don’t sound as clear as they are loud. Others are made exclusively to sound very clean, so they won’t be pounding on your skull like a jackhammer, but the sound they produce is pleasing to the ear. Most of you are concerned about weight in the car, so a single 10 is a great choice. These are great all around for any style music and can get loud enough for you to want to turn it down. I use a single 12 and it’s plenty. I went through a bunch of brands and configurations and find this works best for me, personally. Some of you have heard my Mitsu and know what that was like. Once the Audi is built you can come check it out if you’re on your way to get some equipment for your own car or just feel curious to see what I’ve been yammering about for so long.
Amplifier
You don’t have to have a speaker amp, but you definitely need a subwoofer amp. I’d recommend 250-300 watt RMS for a starter amplifier. 500 is enough for most people. When you pick out an amplifier you should definitely ask for advice from people that work in the shop you’re in or from people that compete. They will be able to tell you about clarity and things they liked and disliked. For people that are not into sound it’s very hard to pick out an amplifier, because it’s tough to really hear the things u need to if you don’t know what to look for. For a subwoofer amplifier you want a monoblock amplifier (this means it’s a single channel) if you’re using only one subwoofer. Some of the larger output amplifiers can still be a monoblock and have enough power for 2 subwoofers. If you’re looking for a quality piece, you should remember a 1:1 proportion. This is a ratio that I’ve noticed with good amplifiers. This denotes 1 watt per dollar spent. Sometimes it’s a little over a dollar per watt, but in general its in the 1:1 range. Many companies advertise very high numbers on the output, but there are some things to keep in mind. Most of them use very cheap components and that really shows once you hear the amplifier. They can advertise 6000 watt, but in reality you’re getting maybe 800 RMS. They can do 6000 peak, but its in perfect lab conditions with 100% efficiency. Remember, you’re going getting 100% in your car due to many factors. Whatever the amplifier box states isn’t always true, make sure to get the RMS number, because that’s what you will be hearing. When you’re picking out an amplifier make sure it can have an output at the same impedance (resistance measured in Ohms) as your subwoofer. It’s easiest to match the two up. If you go with a higher impedance subwoofer it will require more power, it won’t be as loud but it will sound very clean vs a low impedance subwoofer. 2 to 4 ohms will be a nice sounding subwoofer with an amplifier to match that. Once again, I’d like to remind you that when choosing an amplifier looks shouldn’t matter unless it’s a show only piece. If you’re not using anything like a sound processor or a good equalizer make sure the amplifier has a nice built in crossover, so unneeded frequencies don’t go to your subwoofer and make it sound weird. If you’ve decided to go with a higher power amplifier, make sure you can supply it good power. If the current draw is high and you’re pushing it but not fully supplying the amplifier you won’t get the wattage you’re hoping for and can possibly damage the equipment. Amplifiers are just like all the other products above. A new model comes out every year or two, so take your time to pick one out especially at the end of the season.
Power capacitor/2nd battery
These things are a good idea to have in any car, but they’re not 100% necessary. What these things do is help with evening out the current. When your bass hits the amplifier drains more power causing a dip in the current flow. You don’t want to get those dips or peaks in the current. Have you seen people’s lights dim and you hear their bass rattling their trunk? This is what’s happening. This is not good for the car’s electricals and the alternators strain. A lot of people have had to replace their alternators because the demand from the amplifiers is too high and things break. From my experience a 1 Farad (capacity measuring unit in power capacitors) should be good for 600 watt or more. A single 0.5 Farad capacitor (or sometimes referred to as a stiffening cap) is good for under 600 watt. In general most of the capacitors are all the same. You don’t have to go with a fancy one with a blue/red/green volt display on it. Just get one that works. Most people don’t need to see the volt gauge. A 2nd battery is recommended for people with very high amounts of power in the amplifiers they use or people that compete in SPL. Most of you will not need to add another one.
Wiring
Wiring is also important in a system. You should make sure that you have the correct wire gauge for you amplifier and match it with a ground cable for the amplifier. For most people a regular amplifier install kit will do the trick. I won’t go too much in depth on wiring, because most of you will not see the benefit of spending 5 dollars per foot on an RCA cable that spans the length of your car 5 times over. Regular cables will work just fine for your average setup. Keep in mind that better cables are never a minus. If you’ve got some extra money in your budget, get the better wire, it will only do good. Some cars have old and bad speaker wire, so you may need to grab some new wire and just lay in new speaker wires. Some newer cars can still use the factory harness. With the setup I’m building I have to lay all new wires in my car. Even though it’s still good, I can’t use the factory wiring. I won’t get into an explanation of that, I will maybe cover it in the projects thread.
Misc Accessories
You can always add in small accessories such as volt meters to your system. A typical system doesn’t need one, but it wont hurt to have one just incase of problems. It help diagnose and troubleshoot. If you’re using more than one amplifier you will need a fuse box/distro block to spread the power to components and protect them from a power surge. When you’re installing a subwoofer amplifier you will find a single fuse block in the install kit (provided you went that route). Make sure that the fuse you end up using matches whatever is on the amplifier. Some amplifiers have 2 or more smaller fuses instead of one big one, so just add those numbers up and match it with the one on power cable.
Tuning
Tuning is a very tricky process. I would recommend you take your car to a shop to get it tuned. I have been doing this for a while and I still take my car to get tuned. I can it but I still need a pro to polish it up after I’m done. You can’t just read about tuning and be able to do it. Only real way to get it is to keep doing it for years and actually train your ears. Only experience counts here. It’s a little more helpful if you’re a musician, but it doesn’t really matter if you’ve never tuned a car before. If you can’t find a shop to tune your car, ask somebody that’s into SQ to help, those people will either be able to tune it at least some or recommend a place to go to.
I hope this has been informative for you guys and that it will help you make smart decision when building your own setup. Feel free to ask me questions if something is unclear or if you want more information on a particular topic. If you want to know the list of my components or what brands I prefer or would advise to use, just let me know and I can post it. As always, my word isn’t the end-all. This is an advice type thread and I do not claim to be an expert in any way. What I write is from my experience and doesn’t mean you have to make it your Bible. There is always enormous amounts of information available on the net or in books. Here is a website that I think will be pretty useful for beginners. http://www.caraudiohelp.com/ They cover some of the topics I’ve covered, but it’s a good read. It’s well written and is a fast easy read. If you think you will be building a system, you should definitely read through it. Knowing more won’t hurt at all; you’ll just be able to make a better informed decision when the time comes. Don’t you guys wish I was into engine tuning instead? ;D All your cars would be running perfect :nod :lol
wow i wish i had the time and patience to read all of that :lol i actually read the first line about if you have ADD :crackup
anyways it seems that you post up some good stuff for audio installments and making things sound good…keep it up :number1 :bow
In your section about crossovers I think your focusing too much on how they look rather then their function. I have a strong home audio background and have made a few crossover networks over the years and most any serious speaker manufacturer would agree that the crossover is the heart of the speaker system, at least as important as the raw drivers being used. In fact its the only part of a speaker high end manufacturers conceal and will not disclose, everything else is common knowledge, from the drivers used, the cabinet and its construction to the internal wiring. Crossovers can make, or break, a systems musicality. Inexpensive active crossovers are garbage, while its a simplier circuit it does something funny to the sound and makes it sound “hi fi.”
my 
I’d add two things to your wiring section, first is a common mistake for novice car stereo folks so its worth mentioning, don’t run your RCA’s on the same side of the car as your power cable, its the best way to introduce noise into the system.
And the other is probably less of an issue, but worth adding, more does not always equal better with cables, in particular with silver cables. I’ve never heard a silver cable in my system that I liked, ever. Back when I was into mega buck audio equipment I had a 4 foot interconnect that was $6400, while it was worth it to me at the time in the mobile environment the benefits over a $400 cable may not be evident. Clearly the law of diminishing returns is a factor with cabling and it kicks in faster with mobile audio then it does with home audio. So buy quality, but don’t feel the need to shoot for the stars because you will probably be let down.
I honestly know nothing about home audio, so i dont know what those guys do. Crossovers are pretty important if the one on the headunit sucks noodles.I dont know if they can make or break the system, it was never an issue with me. It’s very likely due to the fact that when I ran passives I wasnt into SQ. When I started to build a more serious setup I went to active and never had problems.
I think you did a great job as a whole, don’t take my comments as insults, not that I’m under the impression you are. You clearly spent a long time putting all of that together and there really isn’t any misinformation present. 
Hey, Vadim I am not sure if you know but you are a moderator in Audio section now. Thank you for posting all your articles, I’ll add some when my school work load gets lighter after the finals :).
no no, not at all. i welcome other info that i may have not mentioned. if u want to post home audio tips then go ahead, i dont really know anything usefull enough to make a writeup.