What are the power amplifier parameters and how to calculate the power amplifier power

Power Band Width: The vocal range is 20Hz 80kHz, and the frequency response of the speaker from bass to treble requires a response capability of 20Hz 20kHz. However, the frequency response of the power amplifier, which is the "bottleneck" of signal transmission, is required to be wider, such as:

7Hz 80khz Hz to ensure the integrity of the signal.

Signal-to-noise ratio. signal to noise ratio): This is the parameter that most directly reflects the quality of the power amplifier, generally above the ratio of 80db, and high-quality products often reach more than 105db, the pursuit of pure sound bottom, can not be ignored.

Two. Distortion (THD): This can be combined with two other important indicators of the amplifier: power rating.

RMS) and peak power. When a power amplifier works at its RMS power, the distortion should be relatively small, generally up to this range. peak power or bridging, the signal may be distorted, clipped, etc., and the ratio will be high:

1% is normal. The smaller the ratio, the better.

The output power of the power amplifier is related to the power supply voltage, load impedance and power amplifier configuration, mainly in the following ways:

1. The maximum non-distortion power is generally based on the sine wave of 1000Hz, and the output power when the distortion is less than that. This power is more reliable. （p=u^2/2r)

2. The maximum peak power, which is based on the maximum output voltage, and the maximum power without considering the actual distortion can be twice the maximum non-distortion power. (p=u^2/r)

3. The maximum peak-to-peak power, which is based on the peak-to-peak value of the output voltage, also does not consider the maximum power of distortion, which is 4 times of the maximum non-distortion power. （p=2u^2/r）

In parentheses is the expression of the relationship between power and power supply voltage U and load resistance R. ）

The u of the above expressions is much greater than 10V, so the saturation voltage drop of the output tube is not considered.

You don't have to count how many watts.

1. The power amplifier has output power and impedance.

2, for example, 4-8 ohms, 100 watts, 4 ohm speakers are 100 watts, and 8 ohm speakers are 50 watts.

3. The peak power is 500 watts (miscellaneous brand), which is the virtual standard power, and the actual power is only 50-100 watts.

4. The maximum power consumption of the power supply is decelerated by 20%, which is the actual output power. For example, the maximum power consumption of the power supply is 300 watts, and the output power of the power amplifier is about 240 watts.

（vcc+vee）*（vcc+vee)/(8*rl)

This is the nominal output power of the amplifier.

It should be 2 to 3 of the speaker's nominal power as well.

Answer: Hello, output power, you need to set the load conditions. For a constant resistance power amplifier, assuming that the voltage gain is sufficient and ignoring the saturation voltage drop of the output tube, the maximum voltage swing that can be achieved at the output terminal is close to half of the supply voltage (or the voltage value on the positive or negative side for OCL circuits powered by positive and negative power supplies), then the maximum output power is the square of this swing value divided by the load impedance; And because the effective value of the sine wave is one-half of the root number of its maximum value, the effective power of the sine wave is one-half of the maximum output power; The rated power is determined by the efficiency of the amplifier circuit and the allowable dissipated power, which is generally less than the effective power of the sine wave.

The general case is calculated as follows: the square of the output voltage of the amplifier divided by the speaker impedance. For example, if the speaker is 8ohm, the output voltage is measured to be 10V, then 100 8 is not very accurate, which is related to the circuit, such as OCL and OTL circuits).

This power is generally measured by professional tools, such as oscilloscopes, millivoltmeters, signal generators, using sine waves to connect the power amplifier to the load, when the waveform is adjusted to the maximum without distortion, read the voltage on the millivoltmeter, and calculate it with the P=U square resistance formula. If the output voltage is 10 volts and the impedance is 4 ohms, the power is (10*10) 4=25W.

Power Power, C-Mood Mode, Test Test, Tape, Tuner Tuner, Bass Bass, Treble Treble, Echo, Delay, 15ms15ms.

20ms20ms, 25ms25ms, 30ms30ms, hall, music**, live, theater, center center speaker, rear rear speaker, subwoofer, balance.

The parameters of the power amplifier indicate that the power amplifier can not exceed the range when it is used, and it can be used reasonably, otherwise it will reduce the life and accelerate the damage of the power amplifier. The main parameters are: input voltage, power amplifier input power, power amplifier rated output power, output impedance) audio input signal voltage (millivolts), etc.