Outputs (48)

A stable time domain BEM for diffuser scattering (2007)
Presentation / Conference
Hargreaves, J., & Cox, T. (2007, September). A stable time domain BEM for diffuser scattering. Presented at 19th International Congress on Acoustics, Madrid

Boundary Element Methods (BEMs) may be used to model scattering of sound by surfaces such as diffusers, accelerating prototyping of new Room Acoustics treatments. Unlike the more widely used frequency domain method, the time domain BEM is usually sol... Read More about A stable time domain BEM for diffuser scattering.

Time domain boundary element method for room acoustics (2007)
Thesis
Hargreaves, J. Time domain boundary element method for room acoustics. (Thesis). University of Salford

This thesis is about improving the suitability of the time domain Boundary Element Method (BEM) for predicting the scattering from surface treatments used to improve the acoustics of rooms. The discretised integral equations are typically solved by m... Read More about Time domain boundary element method for room acoustics.

A stable transient BEM for diffuser scattering (2005)
Presentation / Conference
Hargreaves, J., & Cox, T. (2005, October). A stable transient BEM for diffuser scattering. Presented at 150th Meeting of the Acoustical Society of America, Minneapolis

Boundary Element Methods (BEM) may be used to model scattering from hard rigid surfaces such as diffusers. They have the advantage over volumetric methods that only the surface need be meshed and the surface velocity potential found. Unlike the mor... Read More about A stable transient BEM for diffuser scattering.

Improving the bass response of Schroeder diffusers (2003)
Presentation / Conference
Hargreaves, J., & Cox, T. (2003, November). Improving the bass response of Schroeder diffusers. Presented at IOA Soundbite, Oxford

Room acoustic diffusers can be used to treat the acoustics of critical listening environments. A Schroeder diffuser is a popular type of diffuser which has the property of producing grating lobes of similar energy at most integer multiples of the des... Read More about Improving the bass response of Schroeder diffusers.

A high-frequency BEM for 3D acoustic scattering
Presentation / Conference
Hargreaves, J., Lam, Y., Langdon, S., & Hewitt, D. A high-frequency BEM for 3D acoustic scattering. Presented at 22nd International Congress on Sound and Vibration, Florence. Italy

The Boundary Element Method (BEM) is a powerful method for simulating scattering of acoustic waves which has many advantages, particularly when the problem concerns an object in an unbounded medium. Its applications are however limited in practice be... Read More about A high-frequency BEM for 3D acoustic scattering.

Acoustic cross-energy measures and their applications
Presentation / Conference
Hargreaves, J., & Lam, Y. Acoustic cross-energy measures and their applications. Presented at The 22nd International Congress on Sound and Vibration, Florence. Italy

Acoustic energy density and acoustic intensity are quantities which are well established and widely applied. When these are applied to pressure and particle-velocity fields which are the linear superposition of more than one wave they naturally separ... Read More about Acoustic cross-energy measures and their applications.

Towards a full-bandwidth numerical acoustic model
Presentation / Conference
Hargreaves, J., & Lam, Y. Towards a full-bandwidth numerical acoustic model. Presented at Forum Acusticum, Krakow, Poland

Prediction models are at the heart of modern acoustic engineering and are used in a diverse range of applications from refining the acoustic design of classrooms and concert halls to predicting how noise exposure varies through an urban environment.... Read More about Towards a full-bandwidth numerical acoustic model.

Perception of noise from large wind turbines (EFP-06 Project)
Report
(EFP-06 Project)

Is noise from large wind turbines more annoying than noise from small wind turbines? This is a question that is discussed widely in the context of a new generation of large wind turbines replacing the traditional smaller ones. To date legislation ta... Read More about Perception of noise from large wind turbines (EFP-06 Project).

Perception of noise from large wind turbines (EFP-06 Project)
Report
(EFP-06 Project)

Is noise from large wind turbines more annoying than noise from small wind turbines? This is a question that is discussed widely in the context of a new generation of large wind turbines replacing the traditional smaller ones. To date legislation ta... Read More about Perception of noise from large wind turbines (EFP-06 Project).

Implementing wave field synthesis in an ITU spec listening room part 2: Bass without modes
Presentation / Conference
Hargreaves, J., & Wankling, M. Implementing wave field synthesis in an ITU spec listening room part 2: Bass without modes. Presented at Reproduced Sounds 2011, Brighton

In recent years various sound reproduction systems have been proposed which attempt to use multiple transducers to tame the modal behaviour often prominent in rooms at low frequencies. Of particular interest is the Controlled Acoustic Bass System (C... Read More about Implementing wave field synthesis in an ITU spec listening room part 2: Bass without modes.