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Loudspeaker measurements

Headphone measurements

Acoustics and 3-D audio consulting

Grand & vertical pianos

KAR HRTF measurements, analysis, evaluation and implementation

Head-related transfer function (HRTF) measurements determine the effects of the human body - especially the torso, pinnae and head - to the sound that arrives at the entrance of the (blocked ear canal). The measured / modeled impulse responses can be applied to produce three-dimensional sound, corresponding to our natural spatial hearing percepts. Moreover, the HRTFs reveal the complex phenomena that the sound waves undergo when arriving to the ear canal as well as the high inter-individual variability in the spatial hearing cues and in the perception thereof.

During 1996 - 2005 I researched in-depth human spatial hearing at the Helsinki University of Technology. I devised a high-quality fully automated HRTF measurement / multi-modal experimentation system that I utilized for extensive HRTF measurements. The most work I did using MATLAB, including the measurement system real-time control as well as data analysis and visualization. I can only estimate how many tens of thousands of line of code I have written.

I have measured more than 200 heads (subjects) and made nine wide-scale perceptual / behavioral experiments of more than 70 subjects. The resuls are published in my numerous publications and in a book form with completely new analyses in my PhD Thesis HRTF repeatability: Analysis of Head-Related Transfer Function Measurements, 383 pages. During my academic career I have been the single basic researcher concentrating on HRTFs in Finland. See more of my research involvements in the next Section, titled Research.

Moreover, since 1996 I have been doing lots of electro-acoustical measurements for several clients, and written popular articles related to spatial hearing, audio and acoustics and information technology for Finnish magazines.

Acoustics and 3-D audio consulting

If you're laboratory / company need advice on acoustics and / or 3-D audio, e.g., is planning a HRTF-related project or seek for natural (spatial) sound reproduction solutions, don't hesitate to contact me.

KAR HRTF measurements at HUT/Acoustics