Talk about the rumors and analysis often encountered in power amplifiers!

Talk about the rumors and analysis often encountered in power amplifiers!

Summary

Talk about the rumors and analysis often encountered in power amplifiers!

Talk about the rumors and analysis often encountered in power amplifiers!
Rumor One
Among different brands, low-power amplifiers sound more powerful than high-power amplifiers.

Parsing

1) The measurement standards for power are different between the two brands. The actual power of a low-power amplifier is indeed greater than the power of a larger nominal power amplifier.

2) The power measurement standards of the two power amplifiers are the same, but the sensitivity is different. The sensitivity of the lower power amplifier is higher.

3) The test is not done with the same equipment and under the same conditions, just by personal feeling.
Rumor 2

My speaker burned out because your power amplifier is emitting DC.

Parsing

1) The power amplifier does produce DC, and the DC protection circuit of the power amplifier fails.

2) If the DC protection circuit of the power amplifier is tested to be normal, then it is not that the power amplifier has produced the DC speakers. The main reasons are:

a. The power amplifier does not have a voltage limit protection circuit, and the input signal is too large, which causes the output signal to produce clipping (square wave) and the output super distortion power burns the speaker;

b. The power amplifier has a voltage limit protection circuit, and the input signal is too large to exceed the control range of the voltage limit protection circuit, causing the output signal to produce clipping (square wave) and the output super distortion power to burn the speaker.

3) For some power amplifier products, if the protection light (PROT) can light up normally, even after a failure, it can be judged that the DC protection circuit of the power amplifier is normal, and the protection light is on but the protection function fails. It is very rare.

4) The speaker wiring is reversed (sometimes).
Rumor Three

The power amplifier flashes red easily (CLIP)

Parsing

This is related to many factors. The CLIP indicator circuit of some power amplifiers is calibrated by an instrument. The test signal used is a 1KHz sine wave. However, the frequency response of this indicator circuit may not be flat and sensitive to high frequencies. Therefore, if there are high frequency components in the music signal (such as electronic music) during certain periods, the red light will turn on early. If (CLIP ) The indicator light is only flashing, which is normal and there is no problem to continue working.

Other reasons may be that the load carried by the power amplifier is very low (multiple speakers are connected in parallel), or that the sensitivity of some speakers is particularly low.
Rumor 4

There is no noise when other power amplifiers (peripheral) are connected to yours.

Parsing

1) Generally, there is a problem with wire connection and wire welding. Please check the standard specifications for wire connection and welding.

2) Another reason: some engineering companies use a metal 19" rack, and the ground loop of a piece of equipment on the rack has been fixed to the rack by the panel fixing screws. When our products are all fixed on the machine with screws Another ground loop problem was formed when the rack was installed, which caused noise. It is possible that other domestic equipment does not have this problem. This can only be caused by inconsistent grounding methods between manufacturers.
Rumor 5

The tones of the left and right channels of your EQ are different.

Parsing

1) There is a slight deviation in the position where the GAIN of the two channels of EQ is adjusted to 0dB, which causes the gain of one EQ to be larger than that of the other, just like two power amplifiers with the same power and different sensitivity are louder than the other. It must be the gain. The channel sounds better, clear and loud.

2) At the same time, it also gives us an enlightenment that the special position points such as 0dB of the device must make the potentiometer feel like a positioning point.
Rumor 6

Use the same brand and the same model of speakers, try the same model of products, this batch is lower than the previous batch of products.

Parsing

First of all, in a standardized factory, the BOM determines everything about the product, including appearance, performance, etc. To change any feature of the product, you must first change its BOM. After excluding the “cutting corners” of manufacturers, there are basically the following reasons:


1) There is a difference in sensitivity. Due to the variable value of the device constituting the sensitivity adjustment, the sensitivity of the power amplifier is reduced, resulting in the illusion of power reduction.

2) The speaker unit for the audition has been replaced. Although it is the same model, the power and sensitivity are completely different.
Rumor 7

Use your 500W power amplifier to push the 300W speaker, it will flash red (CLIP) soon. Replace it with another domestic power amplifier with less power than yours. It pushes well and does not flash red.

This question is the same as mentioned above:

1) There is the question of whether the measurement standard of power amplifier power is unified;

2) Whether the sensitivity of the power amplifier is consistent;

3) Whether the nominal sensitivity of the power amplifier is consistent with the actual sensitivity;

4) The sensitivity of the other domestic power amplifier is higher than the sound accuracy (many domestic power amplifiers will use this method);

5) The clip lamp (CLIP) of another domestic power amplifier will not flash (some domestic brands do this);

6) The power of the other domestic power amplifier is indeed greater than the sound accuracy;

7) Is the test method of the speaker's nominal power standard? Does it adopt the same test standard as the power amplifier?