At present, it seems that the use of symmetrical dual-speaker design for cell phones is the trend of the future, and from an acoustic point of view, this is the technology that can really show the effect, however, from the history of the development of the music phone, we are only going back to the design of 10 years ago.
Let's start with a brief overview of the auditory system. We all have one ear on each side, and when a sound source reaches the ear, there is a time difference, a phase difference, and a sound level difference, and the auditory system is based on these three elements to localize the sound.
And then simply popularize the sound system. In the sound system, the speakers are pairs of appearances (square dance ...... that exception), between them to form a sound field and "conjugate", we feel in the middle of the sound field from all directions of the sound, enjoy the wonderful music.
Now back to business. It's not true that a phone with two speakers is called a dual-speaker, and there are very few phones on the market that can claim to have symmetrical dual-speakers that are ergonomically correct.
In fact, most of the early music phones already had symmetrical dual-speaker designs, with the 2013 launch of "The new HTC One" being one of the best of the bunch. However, as the appearance and functionality of the phone has evolved, few phones can now accommodate two identical speakers, and therefore only one speaker is designed, or the upper earpiece is borrowed. In the past two years, the real dual-speaker phone, the 2018 launch of the "Mate 20 X" counts as one.
That's why music phones today are simply going back to the design solutions of 10 years ago.
So what are symmetrical dual speakers with ergonomic acoustics?
First, there is a high-quality sound decoding chip. The chip decodes the digital signal into an analog signal, and drives the speakers through an amplifier circuit, which plays a role in the audio system.
Second, the two speaker process must be the same . Speakers have several important indicators, such as frequency response range, sensitivity and power, as well as the structure of the cavity, if there are differences in parameters, will not be able to normal conjugation.
Third, the formation of effective sound field for the human ear to locate. If the distance between the speakers is too small, it must not pull the sound field, the human ear can not locate the sound field in the "conjunction", but also lost the significance of the dual speakers.
Currently, the sound decoder chips in cell phones support dual-channel sound, depending on the design of the two speakers.
Some phones, with only one speaker at the bottom, use the earpiece as the second channel to output sound when in landscape, but because the parameters of the earpiece and speaker are inconsistent, the result is that they can't be conjugated properly, and the sound effect is not ideal. There are also some cell phones, the two speakers are designed in the bottom, close together, the formation of the sound field is too small, the human ear can not locate, in addition to a little louder, and no practical significance. There are also some phones that are designed with dual speakers at the bottom, but one of them is actually a microphone ......
Therefore, as a music phone, at least designing a symmetrical dual-speaker design that conforms to the human body's acoustics is the way to go.