!"#Large-scale Sound SynthesisStefan Bilbao - 2010Acoustics and Fluid Dynamics Group/Music

Physical approaches to audio synthesis and effects modeling…using mainstream simulation techniques.

Suitable for:

•virtual musical instrument modeling• modular synthesis evironments• speech synthesis• virtual analog effect modeling• spatial audio rendering

OVERVIEW

Time-domain Acoustic Simulation

106 107 108 109 1010 1011 1012 1013 1014 1015 1016 1017

Floating point operations/second, at 48 kHz:

wind instruments

single string

plate reverberation

bass drum

full piano

speech (1D) Small-medium acoustic spaces

Large acoustic spaces

Computational Complexity

single-core CPU GPGPU HPC Unattained (2010)

Cray Jaguar peak performance (2009)

• Generally scales strongly with: nD volume, dimension, audio sample mode density• General lower bounds on complexity follow from basic physics:

Virtual analog effects modeling: electromechanical effects, such as plate

and spring reverberation, distortion, amplifier modeling

Advantages over traditional sampling-based techniques:

•Very high-fidelity audio output•Simplified (physical) control•Direct spatialization

Difficulty:•High computational expense

Solution: exploit parallelism and GPU architectures?

Connect excitation element/insert sample

Read values

x

Time-domain Methods

develop time-domain recursion (audio sample rate, e.g., 44.1 kHz, 48

kHz, etc.)

Musical instrument modeling: brass, strings, percussion, keyboard instruments

Other applications: Spatial audio rendering,

room acoustics simulation, speech

synthesis

Choose computational grid (FD, FEM, Sepctral,

etc.)I/O

AUDIO OUTPUT

CONTROL INPUT

Modular synthesis environments for composers.

• Suitable for all problems in musical acoustics•An especially good match to nonlinear problems…

GPU Solution • Time-domain updates can almost always be written in terms of matrix multiplications/linear system solutions• Matrices are in general sparse (banded) and exhibit a high degree of structure…suitable for parallel implementation. • This project: investigate the possibility of high throughput in physical audio applications, and develop general-purpose audio tools for GPUs.