The inventor of SRS technology is Arnold Clemens. He is an audio lover. When he was engaged in psychoacoustics research, he found that the localization of three-dimensional sound sources by human auditory system always produced the prototype of SRS technology. You can do an experiment, rub your fingers on your forehead, and then slowly move your fingers to one side of your head so that your fingers are equidistant from your forehead and ears. You will notice that the volume increases and the middle and high frequencies are stronger. In the experiment, rubbing your finger is equivalent to producing a stable volume. Your ears hear the same sound differently from the instructions given to your brain, depending on whether the sound comes from the front or the side. The sound on the side is relatively loud, which is caused by the ear court.
When the sound comes from the front, the auricle reflects many frequency elements from the ear canal, while the sound from the side reflects differently. This way, the sound coming from the side is strong and the arrival time is short, so the ear transmits this information to the brain, which is called brain-related communication function. Because this kind of propagation depends on the volume and direction of sound, sound waves always change during propagation, so you need to provide your brain with the details of the changes so that you can know what you are listening to and from what direction.
The traditional two-channel stereo can't create a stereo surround sound field, not because only two speakers are used, but because the microphone in the two-channel recording has no ear court, so the sidetone can't be like the human ear when recording through the microphone, no matter how many microphones are used. SRS system takes these ever-changing communication functions into account, so that listeners can hear more closely the original performance effect.
Two basic principles
According to the surround sound (reflected sound and reverberation sound) that can reflect the sense of on-site monitoring in stereo signals, SRS records in the left and right channels respectively, adds the R and L signals to generate a total signal (R+L), and then subtracts the two signals to generate two differential signals (R-L and L-R). After SRS processing, the total signal, differential signal and surrounding environment information (reflected sound level and. For microphones and conventional stereos, because the microphone can't hear the differential signals of "L-R" and "R-L", the stereo system can't be copied, and there is no sense of space when playing. SRS processes the differential signal and the total signal, and the final sound conforms to the human auditory system and recovers the spatial information. Thus, through the restoration of the real performance environment, the stereoscopic image is enhanced, and people feel the spatial orientation and distribution of audio-visual images subjectively.
Three applications
After SRS processing, it has a very amazing effect on live recorded programs (concerts and movies). If the broadcast program source itself has no live ambient sound, such as using multi-channel pre-recorded CD or computer synthesized sound, the effect will not be as obvious as a live concert. SRS can play ordinary stereo program sources and Dolby surround coded programs, and it can also construct a three-dimensional surround stereo field with a sense of space by using a mono signal source, a stereo power amplifier and two speakers.
There are no restrictions on the placement and listening position of SRS speakers. Even if the two speakers are placed very close together, or you walk around the room at will, you can hear the surround sound field with strong three-dimensional sense. SRS can be combined with various existing stereos to form a set of stereo surround sound. Practice shows that the higher the grade of audio, the more it can reflect the style of SRS. In my opinion, a good pair of active integrated room speakers with SRS can become a set of SRS home theater sound system with high cost performance, which is absolutely in line with the principle of personal consumption.
SRS has obtained patent protection in the United States, 17 patents abroad, and 45 patents are being tried worldwide. Existing authorized companies include Sony, RCA, NEC, etc.
Developed and authorized by SRS LABS, SRS 5250S is a three-dimensional audio processing unit for realizing SRS () sound reproduction system, which is produced by SEPONX Company of the United States.
At present, there are also some processors on the market that claim to have SRS function. Pay attention to whether there is a registered trademark of SRS () laboratory at first, and then whether there is a special central adjustment center and space control potentiometer for SRS.
When SRS 5250S is actually used, it should be connected between the sound source and the power amplifier. If there is a frequency equalizer or audio circuit in front of the power amplifier, SRS 5250S should be connected in front of the frequency equalizer.
4. Comparison with Dolby decoding surround sound system
Let's talk about the comparative audition results of Dolby Prologic in SRS surround sound system: using the same two speakers, switching SRS and Dolby several times with a switch, professionals often check whether the rear speaker works when using SRS, but SRS is actually the front main speaker. SRS has higher logical clarity than Dolby, and surround sound is a continuous three-dimensional sound field, which fills the whole space. Dolby surround, on the other hand, comes from five speakers, and the listener feels a planar two-dimensional sound field.
If SRS is placed in front of Dolby, the original plane two-dimensional sound field will become a continuous three-dimensional sound field with a sense of space, which will make people feel a real listening field. The subjective feeling of SRS surround sound is that each sound source is distributed at the point where the sound box is no longer the sound source in the whole three-dimensional space, and the masking effect between sound sources is much weaker than that of traditional multi-channel system where the sound source only comes from several "points", so the definition of SRS is higher than that of multi-channel surround sound. In conventional stereo playback, the background noise is reproduced from two speakers (two points), and the noise is concentrated at two points, while in SRS system, the noise is distributed in the whole space. Compared with the concentrated noise in ordinary stereo system, the background noise of SRS has little interference to the sound signal, so SRS is superior to stereo playback in sound restoration, playback clarity and noise reduction.