Speaker Classification

The number of channels supported by a speaker is one of the important indicators for measuring the grade of a speaker. From mono to the latest surround sound, the following is a detailed introduction:

1. Mono

Mono is a relatively primitive form of sound reproduction, and it was commonly used by early sound cards. When playing back mono information through two speakers, we can clearly feel that the sound is transmitted from the middle of the two speakers to our ears. This recording method that lacks a sense of position is naturally very backward from today's perspective, but it was already a very advanced technology when sound cards were just starting out.

2. Stereo

Monophonic sound lacks the ability to locate the sound, but stereophonic sound technology has completely changed this situation. Sound is distributed to two independent channels during recording, thus achieving a good sound localization effect. This technology is particularly useful in music appreciation, as listeners can clearly distinguish the directions from which various instruments come, making the music more imaginative and closer to the feeling of being on the scene. Stereophonic sound technology has been widely used in a large number of sound cards since Sound Blaster Pro, and has become an audio standard with far-reaching influence. To this day, stereophonic sound is still a technical standard followed by many products.

3. Quasi-stereo

The basic concept of a quasi-stereo sound card is that it uses mono when recording sound, and sometimes stereo and sometimes mono when playing. Sound cards using this technology were once popular on the market for a while, but now they have disappeared.

4. Four-channel surround

People's desires are endless. Although stereophonic sound meets people's requirements for the positional experience of left and right channels, with the further development of technology, people gradually find that dual-channel sound can no longer meet our needs. The emergence of PCI sound cards has brought many new technologies, among which the most rapidly developing is three-dimensional sound effects. The purpose of three-dimensional sound effects is to bring people a virtual sound environment, and to create a realistic sound field through special HRTF technology, so as to obtain better game auditory effects and sound field positioning. To achieve good results, it is far from enough to rely on only two speakers, so stereo technology seems to be stretched in front of three-dimensional sound effects, but four-channel surround audio technology solves this problem very well.

Four-channel surround specifies four pronunciation points: front left, front right, rear left, and rear right, and the audience is surrounded in the middle. It is also recommended to add a subwoofer to strengthen the playback processing of low-frequency signals (this is why 4.1-channel speaker systems are widely popular today). In terms of overall effect, the four-channel system can bring surround sounds from multiple different directions to the audience, allowing them to experience the auditory experience of being in a variety of different environments, giving users a brand new experience. Today, four-channel technology has been widely integrated into the design of various mid-to-high-end speakers, becoming the mainstream trend of future development.

5.5.1 Channel

5.1 channels have been widely used in various traditional theaters and home theaters. Some well-known sound recording compression formats, such as Dolby AC-3 (Dolby Digital) and DTS, are based on the 5.1 sound system. The ".1" channel is a specially designed subwoofer channel that can produce subwoofers with a frequency response range of 20 to 120 Hz. In fact, the 5.1 sound system is derived from the 4.1 surround sound system, but the difference is that it adds a center unit. This center unit is responsible for transmitting sound signals below 80 Hz, which is helpful for strengthening the human voice when watching movies, and focusing the dialogue in the middle of the entire sound field to increase the overall effect. I believe that every friend who has truly experienced the Dolby AC-3 sound effect will be impressed by the 5.1 channel.

Don't think that 5.1 is the pinnacle of surround sound. The more powerful 7.1 system has appeared. It adds two more sound points, center left and center right, on the basis of 5.1 in order to achieve a more perfect state. Due to its high cost, it is not widely popularized . Signal-to-noise ratio.

The signal-to-noise ratio refers to the ratio of the normal sound signal played back by the speaker to the noise signal (power) when there is no signal. It is expressed in dB. For example, the signal-to-noise ratio of a speaker is 80dB, which means that the output signal power is 80dB greater than the noise power. The higher the signal-to-noise ratio, the smaller the noise.

The minimum requirement of the International Electrotechnical Commission for signal-to-noise ratio is that the preamplifier is greater than or equal to 63dB, the power amplifier is greater than or equal to 86dB, and the integrated amplifier is greater than or equal to 63dB. The optimal value of the signal-to-noise ratio of the integrated amplifier should be greater than 90dB. The signal-to-noise ratio of a CD player can reach more than 90dB, and the high-end ones can reach more than 110dB. When the signal-to-noise ratio is low, the noise is serious when a small signal is input, and the sound of the entire sound range is obviously muddy and unclear. Therefore, it is not recommended to buy speakers with a signal-to-noise ratio lower than 80dB, and it is not recommended to buy subwoofers with a subwoofer ratio of 70dB for the same reason.