Digital speaker is a kind of speaker using digital technology. The digital speakers currently in use are: one is complementary digital speaker, the other is digital crossover digital speaker, and the other is the latest power decoding digital speaker ( Also known as true digital speaker).
(1) Complementary digital speakers. The core of this speaker system is a dedicated digital speaker processor. The complementary digital speaker system (speaker plus speaker processor) is based on the room acoustics characteristics and the complementary frequency of the speaker system.
The working principle of this speaker system is: the standard pink noise generator inputs broadband, uniform pink noise to the audio system, and then a special test microphone connected to the computer is used to measure the acoustics in the listening room, and the room Acoustic characteristics sample the factors that affect the frequency response, and store the sampled data in the computer, detect and calculate the unevenness of the frequency response through the brain, and then input the corresponding compensation data to the speaker digital processor, through this The audio signal processed by a processor is sent to the speaker, which can effectively compensate the acoustic defects in the listening room.
(2) Teaching word crossover digital speaker. The frequency division circuit of the loudspeaker has two main categories: power frequency division and electronic frequency division. The most common is the power frequency division method. Electronic frequency division is the frequency division of the audio signal through the analog circuit first, and the audio signal (voltage signal) after frequency division Respectively amplified by the power amplifier, and then push the speaker.
The digital frequency division digital speaker is based on this electronic frequency division theory, but its frequency division circuit is not an analog circuit, but a digital frequency division circuit, using dual 20bit analog/digital (A/ D) The converter converts the analog audio signal into a digital audio signal, and then divides the frequency through a 24-bit digital processing system. After performing independent phase correction on the divided signals, it is also sent to a 48-bit digital limiter. Limiting processing in the circuit.
Usually this kind of speaker system adopts the form of four-frequency division. In order to ensure the processing accuracy of digital signals, the sampling rate of high, medium, low and ultra-low frequency digital audio signals are 2×171 times, 2×31 times and 2×15 times respectively. . The 4 channels of digital audio signals processed above are subjected to independent level control and 48-bit noise circuit shaping, and then added to 4 independent 20-bit digital/analog converters to restore analog audio signals, which are amplified by a power amplifier to drive the speakers.