Which parameters mainly determine the volume and sound quality?

I. Power

Power parameter is actually a basic parameter to measure the performance of multimedia speakers. However, due to the intentional avoidance of manufacturers, power has become a meaningless parameter in many product descriptions.

The marked power of multimedia speakers mainly includes the following contents:

1, Rated Output Power (RMS): RMS power can be said to be the only truly meaningful power labeling method, which refers to the maximum power that the power amplifier circuit can continuously output within the rated distortion range. Also known as "effective power". When discussing the power amplifier circuit, the power we refer to generally refers to the rated output power.

2. Music output power (MPO): refers to the instantaneous maximum output power of the power amplifier circuit under the condition that the distortion does not exceed the specified range.

3. Peak music output power (PMPO): refers to the instantaneous maximum output power of the power amplifier without considering distortion at all.

The latter two forces are meaningless, because their so-called "moments" are often a few milliseconds that can't be heard at all. But many manufacturers are willing to use these two labels, especially PMPO power, because they want to increase the power of their products. Most of the common speakers such as hundreds of watts on the market are like this, and some speakers even mark their own power as 2000 watts!

This is really a joke! The real 2000-watt amplifier and speakers are enough for everyone in your community to hear your music, and even the real 300-watt speakers are enough to make the whole building restless. Can a small desktop speaker do it? No wonder PMPO power supply is nicknamed "JS power supply" by enthusiasts.

According to the general practice, the ratio of PMPO power to RMS power is generally 5-8: 1, that is to say, a speaker with a nominal power of 300W is actually just an ordinary speaker with an output power of about 30W!

Real famous brand manufacturers will not use PMPO power supply. If the product is really excellent, why use this disguise? So seeing PMPO's logo at least shows that manufacturers have insufficient confidence in their products.

Besides the power amplifier, the power parameters in the multimedia speaker also include the maximum bearing power of the speaker and the maximum output power of the power supply. The smallest of these three parameters is the maximum output power of the speaker. Moreover, there is a certain collocation relationship between these three parameters. For example, the root mean square power must be less than the maximum bearing power of the speaker, otherwise it will burn out the speaker. The maximum output power of the power supply should be at least 150% of the root mean square power, and the extra 50% is the so-called "power reserve", otherwise the sound will be distorted when the volume is loud or dynamic (this problem exists in a large number of speakers in the market).

Second, the frequency range and frequency response

These are two basic parameters to identify the speaker's voice reproduction ability. The former refers to the range between the lowest effective playback frequency and the highest effective playback frequency of the speaker, in hertz (Hz); The latter refers to the phenomenon that when an audio signal with constant voltage output is connected to the speaker system, the sound pressure generated by the speaker increases or decreases with the change of frequency, and the phase changes with the frequency. This relationship between sound pressure and phase and frequency is called frequency response, and the unit is decibel (dB).

Generally speaking, there are many frequency ranges marked on multimedia speakers. The larger the scope, the better the effect. But the problem is that many products are not marked with "the frequency range of speakers", but with "the frequency range of power amplifier circuits". This produces a value such as 20 Hz-20 kHz, which covers the range of human hearing.