The Ideal Car Audio System

THE IDEAL CAR AUDIO SYSTEM (For Beginners)

At first let’s make one thing clear. The “IDEAL” car audio system is not necessarily the loudest one, or the most expensive one. It’s the one that best meets your needs.

So the first step is to figure out “WHAT YOUR NEEDS ARE”

If you are an amateur and don’t exactly know your needs or are misled by local car audio installers, then at first lets have a look at what components go into a car audio system.

1. SOURCE (or HEAD UNIT):- The most important part of the car audio system. It is the first step towards sound reproduction. If you go wrong here your whole system will suffer and God help your ears.• Get a good head unit from a well known manufacturer.
   • Looks matter the least. Accurate sound re-production is of utmost concern to us.
   • Look for a warranty and avoid Grey-Market units.
   • For people that are on low budget forget all the fascination of colorful displays, flip panels, inbuilt equalizers, bass boost etc. Just buy a sturdy and well performing head unit which you can value for long.
   • If you like to have hours of music at hand then you could opt for a CD-changer or a MP3 compatible head unit.
   • If you like the thought of your children in the back seat enjoying a blasting action movie then you could go for a VCD or a DVD receiver unit with a display screen.
   • If you are planning to buy an amplifier in future, get a head unit with RCA out puts.
2. SPEAKERS: – The second most important part of your system. Speakers convert the electronic signal into sound waves. They are the reason why we hear the sound of music in the audio system.
   • There are several types of speakers available in different sizes, shapes and (Misleading) power ratings. Beware before spending your money in this section.
   • Power is the most over- rated feature in all head units as well as speakers.
   • I would like to bring to your notice here that almost all companies (even the reputed ones) have a tendency to mislead the customer by rating big numbers to their speakers like 300watts,450watts etc. This is a game of numbers.

   • Never buy a speaker depending upon company ratings like PMPO, PEAK POWER, and MAX POWER etc.
   • The real or rather the most reliable rating is the RMS (Root Mean Square).RMS ratings are the equivalent of the actual power delivered.
   • The next most important thing to remember about speakers is, “PROPER INSTALLATION”.
   • If not installed properly the sound may feel lifeless. The placement of the speakers, the direction of speakers and the height of speakers matter a lot when it comes to a room as small as your car.
   • Usually speaker locations provided by the car manufacturer are not the best, but you can install the speakers in the provided space if you do not want to spend money and bear the pain of seeing your car torn apart for custom installations.

   Now let’s have a look at the kinds of speakers available in the retail market.

   • COAXIALS: – They are two (or more) speakers’ built-in the same frame. They usually consist of a mid-bass and a tweeter or (a set of tweeters). They are cheaper than separate component speakers and easier to install.
   • COMPONENT (SEPARATES): – They consist of separate woofer, mid-bass or mid-range and tweeters (in case of 3-way system) and only mid-bass and tweeter in case of a 2-way system. They are all connected to a crossover supplied along with the set for proper frequency distribution among the speakers. These kinds of speakers are harder to install but give much clear sound and create a much better sound stage.
   • MID-BASES: – They are usually 5″ to 8″ speakers which are designed to go low in frequency and fill the frequency gap between the sound of a woofer and a tweeter. They make the sound seem more life like. But due to their odd sizes and the compulsion of using a cross-over network, they are less preferred by the typical consumer.
   • HORNS: – They are usually funnel shaped speakers and are designed for imaging and staging purposes, they are good at reproducing vocal frequencies and are also the hardest to install and get the required result out of them.
   • TWEETERS: -They are usually 1″-3″ in size and are excellent at reproducing high frequency sounds. They are an inevitable component if you are planning to attain good staging and imaging. But again there lies the same problem of a proper crossover network. Now a days many tweeters are available with in-built crossovers (which is nothing but a non-polar capacitor of a specific value).Tweeters are usually mounted on the dash-board.
   • SUB-WOOFERS: – They are the largest speakers ranging in size from 8″ to 24″ (the biggest I have seen).They are the most important for you if you want to “FEEL” the drum beats and not just hear them. The loud thumping of the dinosaurs in ‘Jurassic Park’ would sound like the foot steps of a horse, without a sub-woofer. They are specific speakers aimed at producing extreme low frequencies as low as 20Hz (only some can reach that low).Ideally a woofer should be installed in an enclosure or a box of specific size and design (there are many kinds of enclosures, we shall not discuss it here). But the rampant kind of installation is the “Free Air” installation also called “infinite baffle”. Here the woofer is mounted in the rear baffle behind the seats and it uses the trunk as an enclosure. Woofers demand maximum power. They should not be used without an amplifier. A low-pass crossover is desirable to be used with a sub-woofer.

   Now let’s clear some more myths about speakers.
   • Speakers can never be damaged by more input power. I would say more the amplification, clearer the sound. So do not fear using a powerful amplifier on a speaker of smaller rating. Always more the power better the sound.
   • Speakers get damaged when they are fed with frequencies they are not designed to handle. Hence the use of a cross-over becomes necessary if you want to save your speakers from tearing off.
   • Distortion in sound is created at higher volumes because frequencies tend to roll off and a phenomenon called clipping starts. This is mainly due to lack of power and proper frequency distribution.
   • The cone and the frame material used in making a speaker are very important as the sound quality differs with every material.

   Let’s look at some commonly used speaker locations in the car.
   • The front speakers are usually located in the dash board or in the door panels.
   • The rear speakers in the baffle behind the rear seats or the door panels.
   • The woofers in the baffle along with the rear speakers, or in the trunk.
   • Tweeters on the dash board or the A-B pillars.
   • Speaker locations are highly subjective to the acoustics of the car interiors, different positions and locations should be experimented upon before finalizing the speaker installation.

3. AMPLIFIERS: – They amplify (or multiply) the input signals from the head unit and send a much more powerful signal to the speakers. They just do not make the system sound louder; they make the system sound better. A common misconception is that if more power is supplied to the speakers they will burn. This is not true, as long as there is no distortion and the speakers are protected by crossovers. More power is always better.• Amplifiers can be classified according to their amplification circuitry (class-A, B, AB, and class D and tube amplifiers) Tube amplifiers are not generally used in car audio.
   • Amplifiers can also be classified according to their channel distribution (Monobloc i.e. 1 channel, 2-channel, 4-channel, 5-channel and now a days even 6-channel amplifiers are available for multi-channel setup.)
   • If you are planning to power only the rear or the front speakers then a 2-channel amp with matching power rating is sufficient. If you want to run all the four channels on amplifier then a 4 channel amp would be more suitable.
   • If you are planning to install a sub-woofer then a Monobloc amp dedicated to the sub-woofer would be more suitable. But they are much costlier. Instead you can buy a bridgeable 2 or 4 channel amplifier and bridge the 2 channels into one to power the sub-woofer.
   • The location of the amplifier is also very important. Since the amplifier produces a large amount of heat, it should be installed in a location where ample circulation of air occurs and it should be kept away from direct sun-light.
   Sub-Woofers demand the most power out of the amplifiers. More power should go to your subwoofer then the combined power going to the rest of your speakers.
4. CROSSOVERS: – They are a combination of series and parallel placed induction coils and capacitors, or either of them. They are given the job of frequency distribution among different types of speaker for distortion free sound reproduction. Inductors stop the high frequencies from passing through and hence can be called low-pass crossovers (they let the low frequencies pass), while capacitors block the low frequencies from passing and hence can be called high-pass crossovers (they let the higher frequencies pass).A combination of these together make a band pass which cut through a certain portion of both the high as well as the low frequencies and are rightly called band-pass crossovers(they let only a certain band of frequencies pass through them).Matching crossovers are usually supplied with component speakers; otherwise they are an expensive affair in the Indian market.
5. SOUND PROCESSORS: – They are external units which process the sound for time delay, phase difference, bass-boost, surround-sound, frequency-equalizer etc. This is done through analog circuitry or digital processing.• One of the digital processors is the “EQUALIZERS”. They allow you to tweak the sound by manually or digitally adjusting different frequency levels. Equalizers as commonly misunderstood, are not meant for boosting a certain frequency, it is usually meant to cut-off undesired frequency in order to achieve a much flatter response. In car audio competition more points are given to a flatter response.
   • Dolby Pro Logic, DTS, Dolby Digital, Other 5.1 surround formats are digitized sound tweaking formats which make you feel the experience of sitting in a theatre rather than a car.
   • These are expensive units and should be bought with great care.
   • These kinds of units should be bought from reputed manufacturers and official dealers only as there is usually a warranty of 1 to 2 years on such units.
6. POWER SUPPLY: – A sufficient and stable power supply is an integral part of any Audio system. All the electrical appliances of a Car run on a 12V DC. The car manufacturer supplies with a power supply enough only for the pre-installed gadgets and a low rating Audio system. If you wish to pump up the jam you need to have a sufficient and more stable power supply than your current power supply. The power supply comprises of a few components as under.• BATTERY: – The main source of power in any car. It is a device which stores current and delivers it to all the gadgets in a car. Most of the gadgets are designed to run on a 12V DC current.
   • ALTERNATOR: – It is a device which charges the battery as long as the car runs. Since the battery can store only a limited amount of energy and can get easily exhausted on extensive stationary use, a compatible alternator is a must. The car manufacturer supply with an alternator sufficient to charge the batter supplied with the car.
   • STIFFENED CAPACITOR: – It is a secondary energy storing device which insures a stable power supply to your audio components. It stores energy for a very short period and delivers it to the components. It is not a battery. But it stabilizes the current and saves the components from being blown off and the battery from being over loaded due to the heavy demand of a high-end audio system. It is not supplied by the car manufacturer. But is an important component of the power supply, if you are willing to run heavy amplifiers and large output speakers and woofers. They are available in various capacities starting from 0.5 farad to 5.0 farad in the Indian market.
   • CABLES AND WIRES: – Last but not the least; they can never be ignored in any car audio system. There are a few things to keep in mind while wiring your car audio system.