An acoustic signal processing device 1 includes: a focal point position determination unit 12 that obtains a plurality of sets of initial focal point coordinates, coordinates of the virtual sound source, and a direction of directivity thereof, and for a pair of sets of initial focal point coordinates with different polarities among the plurality of sets of initial focal point coordinates, multiplies the sets of initial focal point coordinates by a rotation matrix based on the coordinates of the virtual sound source to thereby determine sets of focal point coordinates, the rotation matrix being specified from the direction of the directivity; a circular harmonic coefficient conversion unit 13 that calculates weights to be applied to multipoles including the sets of focal point coordinates from a circular harmonic coefficient; a filter coefficient computation unit 14 that, for each of the speakers in the speaker array, computes a weighted driving function to be applied to the speaker from the sets of focal point coordinates, polarities of the sets of focal point coordinates, and the weights to be applied to the multipoles; and a convolutional operation unit 15 that, for each of the speakers in the speaker array, convolves the weighted driving function for the speaker into the input acoustic signal to output the output acoustic signal for the speaker.

Systems and methods for adjusting bass levels of a multi-channel audio signal include, among other features, (i) receiving the multi-channel signal via a playback device; (ii) separating, from the multi-channel signal, low-frequency signals comprising frequencies less than a threshold frequency; (iii) determining electrical energies of the low-frequency signals; (iv) determining a first energy by summing the electrical energies of the low-frequency signals; (v) consolidating the low-frequency signals into a consolidated low-frequency signal; (vi) determining a second energy by determining an electrical energy of the consolidated low-frequency signal; (vii) generating a gain-adjusted low-frequency signal by adjusting a gain of the consolidated low-frequency signal based on both (a) the first energy and (b) the second energy; (viii) generating a gain-adjusted multi-channel signal by mixing the gain-adjusted low-frequency signal back into the multi-channel signal; and (ix) using the gain-adjusted multi-channel signal to play back gain-adjusted multi-channel audio content via the playback device.

In general, various aspects of the techniques are directed to audio rendering for low frequency effects. A device comprising a memory and a processor may be configured to perform the techniques. The memory may store audio data representative of a soundfield. The processor may analyze the audio data to identify spatial characteristics of low frequency effects components of the soundfield, and process, based on the spatial characteristics, the audio data to render a low frequency effects speaker feed. The processor may also output the low frequency effects speaker feed to a low frequency effects capable speaker.

A three-dimensional (3D) audio reproducing method and apparatus is provided. The 3D audio reproducing method may include receiving a multichannel signal comprising a plurality of input channels; and performing downmixing according to a frequency range of the multichannel signal in order to format-convert the plurality of input channels into a plurality of output channels having elevation.

An audio system with sound-field-type nature sound effect includes: a first primary channel playing device for playing a primary audio signal generated according to a left channel audio signal and/or a right channel audio signal; a first secondary signal circuit for generating a first secondary audio signal according to the left channel audio signal and the right channel audio signal; and a first sound field control playing device connected to the first secondary signal circuit and adapted to play the first secondary audio signal; wherein a first playing delay period exists between the playing of the first secondary audio signal and the playing of the primary audio signal; wherein the first secondary audio signal played by the first sound field control playing device does not undergo audio mixing with the primary audio signal by a first audio mixing circuit.

In some examples, immersive audio rendering may include determining whether an audio signal includes a first content format including stereo content, or a second content format including multichannel or object-based content. In response to a determination that the audio signal includes the first content format, the audio signal may be routed to a first block that includes a low-frequency extension and a stereo to multichannel upmix to generate a resulting audio signal. Alternatively, the audio signal may be routed to another low-frequency extension to generate the resulting audio signal. The audio signal may be further processed by performing spatial synthesis on the resulting audio signal, and crosstalk cancellation on the spatial synthesized audio signal. Further, multiband-range compression may be performed on the crosstalk cancelled audio signal, and an output stereo signal may be generated based on the multiband-range compressed audio signal.

System, device, and method for audio reproduction are provided. The system includes a media computing device and an electronic device connected such that their speakers can be used in combination in optimizing the audio reproduction of media being played or streamed. Each device can be portable and the audio reproduction can include virtual/spatial/surround audio reproduction. When connecting, the media computing device serves as a host and the electronic device serves as a slave for data communication. As such, the media computing device can process an audio signal into any portion for reproduction on any speaker. Further, when connecting and if needed, the electronic device serves as a host and the media computing device serves as a slave for power management. Depending on the system configuration, a suitable connection can be made via a wireless or single cable wired connection between the media computing device and the electronic device.

Embodiments are directed to a speaker system that contains multiple low frequency speakers distributed within a room. Each speaker has at least one driver capable of adequate bass response and an integrated microphone and on-board power and digital signal processing capability. The system has a central sound processor that performs a measurement and calibration process for all of the speakers in the room by receiving test signals from the speakers, measuring certain audio characteristics, deriving audio processing coefficients to smooth the bass response, and transmitting the respective coefficients to each speaker for application to the input audio signals for playback.

The present document relates to methods and apparatus for rendering input audio for playback in a playback environment. The input audio includes at least one audio object and associated metadata, and the associated metadata indicates at least a location of the audio object. A method for rendering input audio including divergence metadata for playback in a playback environment comprises creating two additional audio objects associated with the audio object such that respective locations of the two additional audio objects are evenly spaced from the location of the audio object, on opposite sides of the location of the audio object when seen from an intended listener's position in the playback environment, determining respective weight factors for application to the audio en.) object and the two additional audio objects, and rendering the audio object and the two additional audio objects to one or more speaker feeds in accordance with the determined weight factors, The present document further relates to methods and apparatus for rendering audio input including extent metadata and/or diffuseness metadata for playback in a playback environment.

An audio signal processing method. The audio signal processing method includes: acquiring a first stereo audio signal; splitting the first stereo audio signal into 5.1-channel audio signals; obtaining processed 5.1-channel audio signals by processing the 5.1-channel audio signals based on a speaker box parameter of a three-dimensional surround 5.1-channel virtual speaker box; and synthesizing the processed 5.1-channel audio signals into a second stereo audio signal.

An audio signal processing method. The audio signal processing method includes: acquiring a first stereo audio signal; splitting the first stereo audio signal into 5.1-channel audio signals; obtaining processed 5.1-channel audio signals by processing the 5.1-channel audio signals based on a speaker box parameter of a three-dimensional surround 5.1-channel virtual speaker box; and synthesizing the processed 5.1-channel audio signals into a second stereo audio signal.