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BASICS OF CAR AMPS

1. Reability

Automobile car audio power amplifier is an audio amplifier that use switching power supply for the power transformator

Reability is an important factor in a car audio power amplifier. This is because in cars, power amplifiers are subjected to relatively low impedance speakers and high ambient temperature.

We can calculate output power of an audio amplifier using this equation :

P = V2/8R

where P = power in watt,  V = peak to peak voltage rail, R = impedance of the speaker.

For an example, audio power amplifier with +/- 35VDC supply rail with 4 ohm speaker impedance will produce about 153 watt.

There are 2 factors that limited the output of a car audio power amplifier. First the limitation from the switching power supply and second the limitation of the audio amplifier itself.

We can estimate the output power of a switching power supply by looking at the size of the toroidal switching transformer, the number and the size of the transformator wire it uses, the number of switching power mosfets that it utilizes, and the total amount of the capacitance (mFarad) of its capacitors.

The limitation of the audio amplifier cames from the type and the amount of the output audio power transistors. Power transistor for audio amplifier have several sizes, like TO-220 (50W/pair), TO-247(100W/pair), MT-100(150W/pair), dan MT-200(200W/pair). You can calculate the total amount of the power transistor in an audio amplifier to determinate the maximum power that one audio amplifier can generate. This factor is also determining if one audio amplifier classified as high power or high current (able to drive low impedance speakers in stable condition). If you use one audio power amplifier for loads that is lower than recomended, your power amplifier will be damaged.

Generally, the efficiency of an car audio power amplifier is about 50%-80%. You must conditionize your car electric supply if you want to install high power audio system. For total power above 200W it is recomended that you install extra car battery or replace the car battery with high current dry car battery. For total power above 1000W, you must replace the alternator with the higher performace one. If your car electric system cannot supply the amount of energy for your audio system, the power amplifiers will be damaged. For simple measurement, your car's electric voltage may not drop below 12 V when your audio system is turning on.

2. Sonic quality

Sonic quality is an important thing for measuring the quality of an audio power amplifier. Generally you can determine it by looking at the THD and S/N ratio. The color of the sound is not related to those figures. It is very common that the color of sound determines one's judgement, not the THD and S/N ratios. This is proved by so many people loves the sound of warm tube amplifier, eventhoughthe THD and S/N ratios are low.

The color of sound is relatively subjective and determined by the design of an audio power amplifier. Each people will have different opinion of every brand of power amplifier available in the market. We have general rule in our design not to use excessive amount of op-amps and other components to maintain the quality of the audio signal. For basic design, we have create a design that average people will love the sound it produces. Another interesting thing that nowdays people likes the sound of power amplifier with large power. This is also in our concern. We produces High-End car audio amplifier with high quality and design.

Every power amplifier will be handcrafted according to your need. This is only to reach your satisfaction.