What does louoness mean in amplifiers

The meaning of equal loudness.

Equal loudness control is used to increase the volume of the high-frequency and low-frequency components at low volumes, so that the loudness ratio of the low, mid, and high parts remains the same as at high volumes.

Due to the poor auditory sensitivity of the human ear to high-frequency sounds, especially low-frequency sounds, it is required to make auditory compensation for high-frequency and low-frequency at low volume, that is, it is required to have a large improvement in low-frequency and a certain amount of improvement in high-frequency. In other words, when the volume decreases, the low-frequency part of the signal decreases less, and the higher-frequency part decreases. This requirement is met by equal loudness control, which is typically 8dB or 10dB.

The constant loudness switch is specially designed to boost the low frequency band at low volumes, and it is a low frequency boost circuit added to the center tap of the volume potentiometer. The actual loudness of the sound and the actual loudness of the human ear are not completely linear, at low volume, the human ear will have physiological attenuation of the hearing of medium and high frequencies, and the smaller the volume, the more obvious this attenuation. In order to maintain the equal loudness effect of hearing in the high and low frequency bands when the human ear is relatively loud at low volume, some preamplifiers are inserted with an equal loudness effect circuit, and the principle is to appropriately increase the amplification ratio of the middle and high frequency bands at low volume to achieve the consistency of human hearing.

The isoloudness curve is different for each person, and by balancing the isoloudness characteristics of different people, we can roughly derive the isoloudness curve under different loudness levels of human beings. Equal loudness control circuit is divided into two kinds in principle, one is a fixed equal loudness control circuit, relatively simple, this kind of circuit is generally equipped with an equal loudness switch, when needed to press the equal loudness switch on the line. There is also an advanced linear equal loudness control circuit, with the volume of the volume, the amount of equal loudness compensation will change to achieve the most linear effect, such a circuit often does not have an equal loudness switch, is linearly controlled by the volume potentiometer.

Technically, there are two types of loudness control circuits, such as analog circuits, and other loudness control circuits, such as digital circuits. The digital isoloudness controller can select several different isoloudness curves and achieve complete linear control. The equal loudness control circuit will increase the distortion and deteriorate the signal-to-noise ratio, so it is generally used in car audio and popular amplifiers, and high-end amplifiers and professional amplifiers do not have equal loudness control circuits.

The power amplifier of a constant pressure amplifier uses a fixed voltage.

Constant Voltage Amplifier: The output impedance of the utility amplifier is very small, typically 8 ohms, which is suitable for long-distance transmission. The voltage of the output signal of a certain high-voltage amplifier is suitable for long-distance transmission, and a loudspeaker (speaker) is installed to support the connection of a step-down constant-voltage amplifier with a matching transformer.

In the case of an amplifier with sufficient power to constant pressure, it is possible to connect to multiple speakers for the public address system, but with better sound quality than ordinary amplifiers. "Integrated" should refer to a constant pressure amplifier with a preamplifier, which does not require a constant pressure amplifier to be connected directly to the mixer and microphone and other **.

The output voltage does not vary with the load impedance, i.e. the constant power amplifier of the maximum voltage output audio signal, using deep negative feedback, the output voltage is very stable, and the output voltage of the amplifier connected to the load in the rated power range of the number is very low. In order to reduce the power loss of a long-distance transmission line in a power transmission, it is necessary to use an output transformer, the main output voltage has several kinds, the higher the voltage transmission line loss 70V, 90V, 120V and so on, because the output transformer is used, but on, so that the sound quality is not very good, generally used in the background ** system and cable broadcasting system.

Features of constant pressure amplifier:

Constant voltage power amplifier, if the rated load voltage changes, the power supply changes accordingly. 100V, 10W speaker connected to 70V becomes 5W (100V and 70V power difference doubles). Constant voltage standard.

Foreign is 120V, 240V, domestic constant voltage standard 70V, 100V

Principle of constant pressure power amplifier:

The negative voltage feedback amplifier circuit gives pressure, you alternately output the signal (AC voltage) negative feedback to the input electrometer of the preamplifier, the stronger the negative feedback, the better the performance of the constant voltage output.

The industry's well-known brands are DSP and ABK, two brands of Iron Knight, TKOKO, Power, Pioneer and so on.

When it comes to point achievement, it means the deadline.

The loudness on the amplifier means equal loudness function imitation and switch,Due to the poor auditory sensitivity of the human ear to high-frequency sounds, especially low-frequency sounds, auditory compensation for high and low frequencies is required at low volumes.

The human ear perceives sounds of different frequencies differently when the sound is loud and when the sound is small. For example, the highest and lowest notes you can hear when the sound is normal, and at the low volume, you can't hear the start.

The task of the power amplifier.

Amplify the weak electrical signal from the source (or from the mixer in a professional audio system) to drive the speakers.

Make a sound. The function of the power amplifier is to amplify the weak signal from the sound source or preamplifier and push the speaker to play sound. A good sound system amplifier plays a big role.

The function of the power amplifier is mainly to amplify the weaker signal input by the audio source equipment carefully, and generate a large enough current to push the speaker to play back the sound.

It's called "Equal Loudness Control".

The human ear has poor auditory sensitivity to high-frequency sounds, especially low-frequency Changnasou sounds, so it is required to compensate for the high and low frequencies at low volumes. The function of the Equal Loudness function is to increase the volume of the high-frequency and low-frequency components at low volumes, so that the loudness ratio of the low, mid, and high parts remains the same as that at high volumes.

It's called "Waiting for the Grinding Degree Control". Because the human ear is blind, the degree of perception of different frequencies of sound is different when the sound is loud and the sound is small. For example, the highest and lowest notes you can hear when the sound is normal, but at low volumes, you can't hear them.

Equal loudness control automatically boosts the treble and bass at volume hours so that you hear the same sound as you hear at normal volume.