Perception & Psycho-Acoustics

Posted in My library

On perception and (subjective or objective) testing - Audio - Science in the service of Art, by Floyd E Toole, PhD, at the time Vice President Acoustical Engineering, Harman International Industries, Inc. Very balanced paper about issues connected to subjective listening tests and bias.

Sean Olive took over the baton and wrote a separate blog on the dishonesty of sighted listening tests.

My own tests: On 9 April 2012 a few members of the NL AES section met at the residence of Hans van Maanen, 'mister Temporal Coherence'. We listened to 15kHz brick-wall filtered (and heavily phase-shifted) music and tried to hear a difference with the same music unprocessed. Yes we did hear a difference! Read my little report!

Inaudible High-Frequency Sounds Affect Brain Activity: On the perception (or not) of frequencies above 20kHz

In Nov 2011 we gathered with a group of audiophiles in Stuart Yaniger's residence in Austin TX to enjoy a live concert by Southpaw Jones. Scott Wurcer brought his mic preamps which he described in his articles in Linear Audio Vol 1 and Vol 3. We were so impressed with the quality and realism of his recordings that we asked the artist for permission to post a song here, which he agreed to. Listen to An Army of Kittens and a section of the subsequent applause. (These are large files so will take some time to download)

Golden Ear Specials (note: some of these are uncompressed .wav files so may take some time to load).

For those that have exceptional acute hearing, I have a nice set of six music fragments. Some of these are unprocessed, some have been processed. It is your task to divide the files into the two groups, the processed and the non-processed ones.

If you think you cracked it, please contact me on pm so as not to take away the fun for others ;-). The files have random number names that have no specific meaning other than to identify them. (You may want to download before playing; these are large files). Courtesy Professor Malcolm Hawksford. 7; 61; 88; 232; 522; 923 (cheat sheet: if you can't really hear a difference, here's the effect increased 1000 times. Knowing what to listen for may help).

Another psycho-acoustic riddle: listen to this track on headphones. Decide at which side you hear which tone. Then turn the headphone around and swap L with R and vice versa. Now decide again at which side you hear each tone. Astonishing, isn't it? Thanks to Jürg Jecklin from Jecklin Float fame for bringing this to my attention. (Note: this ONLY works with headphones!).


Want to build one of my designs?

I am flattered but would also like us to agree on a few rules.

My designs are the best I can make them, including reliability and safety. A lot of effort, time and money goes into them, and I enjoy doing it.

Nevertheless, I have obviously no control over how, where or when somebody would use a design of me. Therefore, I cannot guarantee that it will do as advertised in all cases and circumstances. I also have to decline any and all responsibility for any damages, direct or consequential, resulting from the use of my designs. Sorry about that, but that's how my lawyer wants it...

If you want to build one for your own use, go ahead. It would be nice if you would let me know how it all works out.

If you like to use one of my designs for a commercial product, we can discuss the terms of such use. If you plan to make money out of them, I would like to have some compensation for my work and effort as well. Or, if you are in need of a design consultant for a project, let me know. I’m sure we can work something out to mutual benefit.