If you're on Linux and develop on CUDA, then you probably need to replace the default open graphics drivers with nVidia's proprietary drivers. For quick access to CUDA, you can install the drivers directly from software repositories.
I registered "room-acoustics.com" quite some time ago, when my career was pretty much focused on, as you may have guessed, room acoustics. I'm still involved in room acoustics, both academically and in the industry, but my website now covers much more. I therefore decided to register a more personal domain name, which I think reflects better what this website is about. So without further ado, I introduce the new domain name "www.jonsh.net". Continue reading
Next week I'll be presenting a paper on FDTD sources at DAFx-12 which will take place at the University of York. The study was conducted in collaboration with Maarten van Walstijn from Queen's University, Belfast. Here's the abstract: Continue reading
This week, on Thursday 13.9, I'll be presenting some of our work at the "Acoustics and Audio 2012" conference which will take place at Ben-Gurion University. Here's the abstract:
An Integrated Model of Sound Localisation in Rooms
Jonathan Sheaffer and Bruno Fazenda Continue reading
I have decided to spend some time (i.e. procrastinate) improving my home-brewed FDTD model. Apart from a significant (x10!) increase in computation speed, the process of handling arbitrary geometries is now much easier, thanks to a new voxellisation plugin that can read Google Sketchup(C)(R)(TM)(W)(please don't sue me) files directly. Some results are shown in this video, demonstrating an acoustic pulse propagating in a medium-sized recording studio control room.
As part of my supervisor's ongoing research on the acoustics of Stonehenge, I was asked to employ my FDTD model to simulate diffraction effects around the construction stones. Some results are shown in this video. Simulation was performed using my accelerated algorithm, running on a GP-GPU.
A quick demonstration of how waves scatter off a human head; simulated using WaveCloud. White is zero pressure, toward red is positive, towards blue is negative:
Last week at Forum Acusticum I bumped into Gry Baelum Nielsen from Odeon. We started discussing how different room acoustic simulation software handle complex geometries. After she'd claim that such process in Odeon is as simple as clicking a button, I had to try it for myself. In case you have never sput blood and shed tears over this yourself, it is worth noting that in many commercial software handling complex geometries is every modeller's nightmare. You either have to enter vertices, edges and faces manually (which is literally - torture) or deal with issues such as holes and overlapping faces.
So I made a deal with Gry; I will challenge Odeon with any complex geometry I wish, and if it instantly works as promised I will write her a testimonial. Continue reading
I have not been around for a while. I know. Naughty me. But I do have a good excuse this time, as I've been preparing for the EAA's conference "Forum Acusticum 2011" that will take place next week in Aalborg, Denmark. I'll be delivering a paper on a simple method to solve frequency dependent problems in numerical time domain methods within one of the sessions on computational acoustics.
My presentation is scheduled to be on Friday 1-Jul at 8:20.
If you're around - come say hi! The rest of the conference programme is available here.
With a little help from my home-brewed FDTD model and the (very good and very free) visualisation platform ParaView, I have created some 3D animations of sound wave propagation. In this demonstration you can see a wideband acoustic monopole (Gaussian pulse) propagating in a small (6x6x6 meters) room. In the middle(ish) of the room I've put a small panel-shaped fully-reflecting phase-reversing (R=-1) obstacle so it is evident how diffraction occurs. The boundaries of the room are somewhat reflective (Normalised impedance = 9).