Power amplifier function key diagram
Function of each key of power amplifier:
1. Mic1: microphone 1, GA: volume control potentiometer (i.e. volume switch knob) of microphone 1.
2. Bass: Bass potentiometer for microphone 1.
3. Mid: mid tone potentiometer for microphone 1.
4. Tre: tre potentiometer for microphone 1. Then there is no repetition of the following.
5. Input: it is the selection button of sound source. Then the next two buttons are not sure what the function is.
6. Effect: it is the microphone effect level knob. That is to say, the effect volume.
7. Del: delay of microphone effect.
8.rep: echo times.
The key of pioneer 860 power amplifier is described as follows:
Performance index of power amplifier
The main performance indexes of power amplifier include output power, frequency response, distortion, SNR, output impedance, damping coefficient, etc.
Output power: the unit is w. due to the different measurement methods of different manufacturers, there are some different names. For example, rated output power, maximum output power, music output power, peak music output power.
Music power: refers to the maximum instantaneous output power of power amplifier to music signal under the condition that the output distortion does not exceed the specified value.
Peak power: refers to the maximum music power that the amplifier can output when the volume is adjusted to the maximum without distortion.
Rated output power: the average output power when the harmonic distortion is 10%. Also known as maximum useful power. Generally speaking, the peak power is greater than the music power, and the music power is greater than the rated power. Generally speaking, the peak power is 5-8 times of the rated power.
Frequency response: refers to the frequency range of the power amplifier and the unevenness within the frequency range. Whether the frequency response curve is straight or not is generally expressed in dB. The frequency response of home hi-fi power amplifier is generally 20Hz-20KHz plus or minus 1dB. The wider the range, the better. Some of the best power amplifier frequency response has been achieved 0 — 100kHz.
Distortion: the ideal amplifier is to amplify the input signal and restore it faithfully without change. However, due to various reasons, compared with the input signal, the amplified signal often produces different degrees of distortion, which is called distortion. Expressed as a percentage, the smaller the value, the better. The total distortion of hi-fi power amplifier is 0. 03%–0。 05%. The distortion of power amplifier includes harmonic distortion, intermodulation distortion, cross distortion, clipping distortion, transient distortion, transient intermodulation distortion, etc.
Signal to noise ratio: refers to the ratio of output signal level to noise level of power amplifier, expressed in dB, the larger the value, the better. Generally, the signal-to-noise ratio of home hi-fi power amplifier is more than 60 dB.
Output impedance: the equivalent internal resistance to the loudspeaker is called output impedance.
Function of power amplifier
1. Power amplifier is called “amplifier” by people. Its function is to amplify the weak signal from the sound source or the front amplifier. It can be considered to promote the sound protection of the speaker. You should know that if there is a good sound system, the function of power amplifier is indispensable.
2. As for its function, this is that according to the different components used, “IC power amplifier” is rarely seen in hi-fi because its timbre is not comparable to the two kinds of power amplifiers. Here, simply speaking, power amplifier can be divided into three categories: “professional power amplifier”, “civil power amplifier” and “special power amplifier”. “Professional amplifier” is more suitable for conference, performance, hall, hall, venue, hall. But most of the “professional amplifier” timbre used for Hi-Fi playback, but the sound of this amplifier is hard and hard to hear.