A process includes collecting a digital input signal and performing initial pitch detection to detect one or more pitches on the digital input signal. The process also includes manipulating the digital input signal to form a manipulated digital signal based on the one or more pitches detected.

A timing control method includes generating a timing designation signal according to one of a first generation mode for generating the timing designation signal which designates, based on a detection result of a first event in a performance of a music piece, a timing of a second event in the performance, and a second generation mode for generating the timing designation signal without using the detection result, and outputting a command signal for commanding an execution of the second event according to one of a first output mode for outputting the command signal in accordance with the timing designated by the timing designation signal, and a second output mode for outputting the command signal in accordance with a timing determined based on the music piece.

The implementation of modal processors, which involve the parallel combination resonant filters, may be costly for applications such as artificial reverberation that can require thousands of modes. In one embodiment, the input signal is decomposed into a plurality of subbands, the outputs of which are downsampled. In each downsampled band, resonant filters are applied at the downsampled sampling rate, and their output is upsampled and filtered to form the band output. In these and other embodiments, a feature of responses of the mode filters have been optimized to minimize an aspect of a residual error after a point in time.

A frequency-domain peak detector is configured to detect harmonic content of a digital input signal. An equalizer-based feedback synthesizer is configured to generate simulated feedback at a specified frequency by filtering existing content of the digital input signal at the specified frequency. A tone-based feedback synthesizer is configured to generate simulated feedback at the specified frequency by generating a tone at the specified frequency. Feedback selection logic is configured to determine the specified frequency at which to generate simulated feedback based on the harmonic content, and whether to utilize the equalizer-based feedback synthesizer or the tone-based feedback synthesizer to generate simulated feedback at the specified frequency.

A reverberator based on a room response modal analysis is adapted to produce distortion, pitch and time manipulation effects, as well as gated and iterated reverberation. An example modal reverberator is a parallel collection of resonant filters, with resonance frequencies and dampings tuned to the modal frequencies and decay times of the space or object being simulated. In one example, the resonant filters are implemented as cascades of heterodyning, smoothing, and modulation steps, forming a type of analysis/synthesis architecture. By applying memoryless nonlinearities to the modulating sinusoids, distortion effects are produced, including distortion without intermodulation products. By using different frequencies for the heterodyning and associated modulation operations, pitch manipulation effects are generated, including pitch shifting and spectral inversion. By resampling the smoothing filter output, the signal time axis is stretched without introducing pitch changes.

An electronic musical instrument uses a mouthpiece model that models a mouthpiece as a three-dimensional shape having one end at which the mouthpiece is to be held in a mouth of a performer being smaller than another end. A processor in the instrument calculates a reflection coefficient of a progressive wave and a regressive wave using the mouthpiece model by calculating a wave impedance for the progressive wave and calculating a wave impedance for the regressive wave, and generates a musical sound signal on the basis of the calculated reflection coefficient, which is then outputted to a sound generator for sound production.

Calculation is performed to provide a delay and attenuated oscillation to a blowing pressure detected by a blowing pressure sensor which detects blowing pressure, and a musical sound is generated based on the blowing pressure subjected to the calculation. As a result, for example, a blowing feeling of an electronic wind instrument can be made closer to a blowing feeling of a natural musical instrument.

One embodiment of the present application sets forth a method for simulating an audio output of a three-dimensional object that includes a resonant cavity. The method includes receiving an input mesh of a three-dimensional shape and a hole configuration. The input mesh has an outer surface and an internal cavity, and the hole configuration includes one or more holes. The method further includes adding the one or more holes to the three-dimensional shape based on the hole configuration to generate a modified three-dimensional shape having a resonant cavity. The resonant cavity includes the one or more holes and the internal cavity. The method further includes determining an air pressure coefficient matrix for the resonant cavity. The method further includes computing a minimum non-zero eigenvalue for the air pressure coefficient matrix. The method further includes determining an output resonant frequency for the resonant cavity based on the minimum non-zero eigenvalue.

A system for modifying an audio signal comprises a computer including a first digital signal processor (DSP). The first DSP includes a first module and a second module. The first module is coupled to the interface to provide a musical instrument with a set of testing input signals and obtain a set of testing output signals from the musical instrument via the interface. The second module is configured to perform functions including: analyzing the set of testing output signals to obtain a set of parameters, constructing an acoustic transducer to model characteristics of the musical instrument based on the set of parameters, and receiving the audio signal to modify the audio signal using the acoustic transducer, wherein the first DSP module obtains the set of parameters at least by identifying occurrences when an output level state determined at least based on the set of testing output signals significantly changes.

Disclosed are a method and apparatus for producing sounds in a virtual world, as well as a sound card. The method comprises the steps of determining a spring mass model of an object in the virtual world based on a 3D model of the object; analyzing force components produced on the 3D model by a collision in the virtual world; and generating sounds produced by the collision according to the spring mass model and the force components. By considering sound material of the object in the virtual world, the method, apparatus, and sound card may produce sounds in the virtual world more vividly and in real time.