ARTICLE: The Team-BHP Guide to BASIC Car Audio

[navin]

The first rule of car audio is to listen. Differences in taste and car acoustics combined with myriad combinations of head units, speakers and amplifiers make it almost impossible to design the ideal system for everyone. While the perfect system for everybody does not exist, with a little effort it may be possible to find the perfect system for you. Remember: it is your money, your car, your music and your ears. Listen before deciding.

When selecting a system, try to choose a large international brand that is widely available and supported by a good service network, like Alpine, Blaupunkt, JBL, JVC, Kenwood, Pioneer and Sony. We recommend buying only from official distributors that offer a manufacturer’s warranty.

• The head unit: Today most head units (HUs) play only CDs – rightly so, since tapes are long past their prime – but there are still a few cassette units available and even some cassette/CD units. Because CD-only HUs are the most common, there is a wider available range of units of differing quality and cost. We recommend buying an HU that is MP3 compatible and preferably ipod compatible. Most HUs come with built-in amplifiers, but you should not believe the advertised power rating: it is usually inflated. These amplifiers normally only produce about 8-12 watts RMS, <0.1% distortion and 20 Hz-20 kHz. While this kind of power is not earth shattering, it should be enough for most uses. HU prices start at Rs.6 000.

• Amplifiers: Amps are used for two purposes: to reduce the load on the HU power supply so that it performs better, and to increase the sound levels of the car audio system. In most cases 35-40 watts RMS per channel is more than enough, but advertised amplifier specs are often optimistic. You should check to see that amplifier distortion figures are less than (<) 0.1%, 20 Hz-20 kHz and that all channels are driven in parallel. Avoid amps that do not meet these specifications. Prices start at Rs.5 000 for a 4-channel amplifier and at Rs.3 000 for two channels.

• Speakers: Speakers contain the fewest parts but probably perfrom the most complex job in an "audio chain" because they convert electrical energy to mechanical – that is why those cones move so much. Many audiophiles believe that speakers have the most influence on overall sound quality.
  
  There are two basic speaker types: coaxials and components. In coaxial speakers the low frequency and high frequency units are molded into a single physical frame. In component speakers the low and high frequency units are separate and include a third part, called the crossover. Component speaker systems are more expensive but offer superior sound quality. To accommodate limited budgets people often use component speakers in the front of the car and coaxial speakers in the rear.

• Wires: The quality of wiring is more important than most people think. Choose only wires manufactured by well-recognized, international brands.
  
  Power wires connect the battery to the HU and amplifiers and provide an electrical ground to the body of the car. Cheap power wires may affect sound dynamics and cause other noticeable disturbances, like headlight dimming at high volumes. Good 8-gauge wire will do unless your amplifiers are particularly powerful.
  
  Interconnects connect the HU to the amplifier. Since most amplifiers are installed in the trunk and most HUs in the dash, these wires typically have to run the length of the car. Because the signal generated by the HU is not powerful, these wires are susceptible to noise. By choosing a reliable set of interconnects you will ensure that your speakers play only music, not static or alternator whine.
  
  Speaker wires connect the amplifier to the speakers. In systems that don’t use a separate amplifier, they connect the HU’s built-in amp to the speakers.

• Installation: We strongly recommended that you use only certified professionals to install your audio system. Do not use the services of untrained installers who can cause serious damage to a car and audio system.

Recommended site for newbies:

http://en.wikipedia.org/wiki/Car_audio

[low_bass_makker]

http://www.bcae1.com/

some very good stuff is avalable on this site.....manily for DIY guys...

[ram_hyundai]

hi,
nice information navin.in this era of car accesories shops where your not charged of fitment and the authorised service centre charging you for their job you enlightend us about the quality which should be maintained in the job.

[spacebar]

What about SUV's and MUV's like the Scorpio, Innova which dont have place for good subwoofers. The innova has places for speakers in the door panels which are way too small and ineffective. Any idea's on how to get good sound in these cars?

[Sam Kapasi]

Hi spacebar,

This thread offers sensible basic advice. For more detailed questions, answers and humour without a cause, I suggest you ask your questions in the ICE section.

It's here.

[somebodystopme]

How do i know if my speakers are component or coaxials. I have pioneer 6991.....

[Vid6639]

those are coaxials. as the name suggests if all your drivers i.e. mid range, tweeter and mid bass driver are along the same axis then it is a coaxial.

A component will have individual drivers i.e. separate mid bass, tweeter, mid range. This will also generally have a separate crossover circuit in a box.

see the glossary thread.

pioneer 6991 are coax.

[shuvc]

Not sure if this Q is relevant here - or whether it requires a new thread.

How important are antennas ?
The same HU can be fitted in any car. Some have no antennas, some power, some fixed. Does it really matter ? Are some HU's more dependent on antennae than others ?

[zeeshan suleman]

Thats some really nice basic information on audio systems, Thank you

[ankur_fox]

What about waterproofing all the wires? These days it rains a lot and it is probably a good idea to encase the wires in water proof materials. I had the misfortune of not thinking about this earlier and now none of my speakers work. Not they are kaput, its just that the wires have shorted out and changing the wires is a tedious job.

[binoy_tharakan]

Originally Posted by low_bass_makker

Basic Car Audio Electronics

some very good stuff is avalable on this site.....manily for DIY guys...

The URL furnished by you directed me to Car Audio Book - Free Car Audio Information which is an excellent option for newbies!

[binoy_tharakan]

Originally Posted by ankur_fox

What about waterproofing all the wires? These days it rains a lot and it is probably a good idea to encase the wires in water proof materials. I had the misfortune of not thinking about this earlier and now none of my speakers work. Not they are kaput, its just that the wires have shorted out and changing the wires is a tedious job.

Its not very easy to 100% waterproof all your wire joints (Wires -normally-are already water proof but not the joints). If the installer prepare the joints just by twisting the copper wires, its very much possible to get them corroded (forming of copper oxide) and eventually makes the joint non-conductive. This is a slow process and your speaker wont stop functioning the next day after the rain bath!

To avoid the problems caused by the water you may get some weatherproof connectors from auto-electrical shops. If you are really serious about the issue soldering the joints which are more prone to the rain water entry is the best option. After making the joints applying a coat of white petroleum jelly serve the purpose more than any other insulator! Finally get the joints insulated with a good brand of insulation tape.

Please post your -further- In Car Entertainment (ICE) queries at http://www.team-bhp.com/forum/ask-gurus/

[navin]

Originally Posted by binoy_tharakan

Its not very easy to 100% waterproof all your wire joints

Th best way is to use heat shrink.

[binoy_tharakan]

Originally Posted by navin

Th best way is to use heat shrink.

Thats an awesome Idea, to those who want to know what is heat shrink-
Heat shrinks are small flexible tubes normally made of PVC based materials. After encasing the wire joints with these tubes a hot air blower is used to heat the tube in order to make it shrink and stick to the joint tightly. If the job is done perfectly it gives almost 100% waterproofing! We do it extensively for outdoor feeder/jumper cable joints in Telecom industry.

But not sure whether any auto-mechanics have the shrinks and hot air gun with them

[amohit]

Wont the plastic sheet used for laminating mobile phones and a hair dryer do the job?
And another dumb Q. Why cant we just use insulator tapes? Isnt that good enough to keep the water out?
Or else, we can put some soldering tin over the joints...that material dosent corode.