Friday, March 13, 2009

headphones testing

Headphone testing

Sennheiser TR/HDR 120, 22 Hz to 19,500 Hz

This is not a success story. I set up the headphones on a desktop at HKNC. The phones came with batteries and adapters for the plugs. Setup was easy. I could not save the sound file, but I was able to play it from the email. The controls for volume and forward/rewind appeared in the email. One feature of the phones I did not like was the “tune” slide-wheel needed to optimize the signal between the transmitter and the phones. If not set just right the signal was less than strong.

I set the phones and the computer volume on maximum; there was no frequency controls. I tested the phones with on deafblind subject and on deaf subject. Hearing loss was severe-profound to profound. Both subjects did not wear hear aids. Neither subject could feel the vibrations from the phones during several sound playback. I removed the pads from each ear phone, but neither could feel the vibration. I asked the subjects to place there hands on the phones, but neither could feel the vibrations.

Possible problems/solutions:

* It seems I could not get sufficient volume. Is it possible to create a file with significantly higher dB output? I would like to raise the volume and the lower frequencies.
* I plan to try ear buds. I have a pair from my iPod.
* A lighter or different phone material – which might reverberate better – might work.

There was literally no recognition from the subjects of any vibrations, even when focused on the task.

We might need to go to plan B for this. I am open to ideas and suggestions.

1 comment:

GB said...

I did some follow up testing of the headphones with sound files from Zach. The files were composed of various frequencies that we suspected would produced the most salient vibratory output for a subject to feel. I asked several folks to feel the headphones with there hands with the padding removed, so that their fingers could touch the actual exterior of the speaker. There was some awareness of vibration on the left and right but it was very slight.

I think it is time this idea be put to rest and we go with the body-mounted extra wii devices to deliver virbo-tactile signals.