Archive for September, 2009

Experimenting with Doppler Sound Effects

EEN502Projecton September 23rd, 2009Comments Off

This project seeks to explore the doppler sound effect in several different scenarios.

In Part 1, the source sound moves towards a listener on the same plane.
Part 1 code and figures
Part 1 sound

In Part 2, the observer is separated from the source sound trajectory by an offset.
Part 2 code and figures
Part 2 sound

In Part 3, the offset remains, but the tone from the source consists of three tones. For this, I chose a major triad.
Part 3 code and figures
Part 3 sound

Part 4 had two different components. The components replicate Parts 1 and 2 respectively, but they add a second observer. The two observers act as “ears” of a listener, and a stereo track is produced as a result.
Part 4a code and figures
Part 4a sound
Part 4b code and figures
Part 4b sound

Here, you can download all five m-files and run them on any copy of MATLAB.
Download M-Files as a ZIP

Conclusion and Results

The sound files with an offset sounded much better than those with the source and observer on the same plane. This is due to the clicking that occurs when the two are sufficiently close together to cause the envelope to tend towards infinity. This problem was mitigated by limiting the maximum values of the envelope, but it is a non-ideal solution, and discontinuities still occur.

When simulating a person’s two ears, the fact that the distance between ears is very small led to the graphs looking very similar. I changed the distance to something unrealistic (i.e. 4 meters) to make sure that the files were working properly.


HAID ‘09

Uncategorizedon September 12th, 2009Comments Off
You can buy a bratwurst and a 0,5 liter beer for just 4,50 euros!

You can buy a bratwurst and a 0,5 liter beer for just 4,50 euros!

Guten Tag!

I’m posting this from my hotel in Germany. It’s my last night here after attending the Haptic and Audio Interaction Design conference at the Dresden University of Technology. I was presenting my work on the control of audio effects using head position estimation. I’ll have the PDF of the poster and paper in the portfolio section soon. There were many very interesting and fun people that I met on this trip. It was just a bunch of people that like to make cool things happen with technology!

Check out a few photos of the trip here:

http://gallery.me.com/pat_okeefe/100244

My apologies for the inferior white balance and focus of the iPhone camera. It did the trick though.