Tactile sound, as used in this experiment with the K-MAD, improves,
sometimes significantly, the experience of music for people with hearing loss.
Subjects with hearing loss, half who wear cochlear implants and half who use
hearing aids, did not all benefit from the device, but the majority did and
some by a lot.
Aside from the ratings, subjects were also asked to provide descriptions of what they experienced. Many gave the same description, saying the K-MAD was “filling in” sounds. They often demonstrated this with their hands forming a circle in the air like they were making a basket under something.
It is likely the K-MAD’s ability to add more sound input to their body from a source other than audio is giving their body more information then they get without the K-MAD. Frequencies they miss in their hearing are coming into their body from the vibrations, or if there are frequencies they do not hear fully with their hearing, the K-MAD is probably giving them the ability to experience more of those frequencies. Two neurologists who spoke to me about the experiment after I had the results said it was possible tactile sound was affecting different senses than audio input does.
As expected, subjects with normal-range hearing experienced almost no benefit from the K-MAD. Research shows that tactile frequencies are canceled out when they match audio frequencies, and these subjects were able to hear the music well.
Cochlear implant users have the advantage of better response in the middle and high frequencies over the hearing aid users, which helped them benefit more from the K-MAD.
Two male subjects with hearing loss exhibited very poor sensitivity throughout the testing and gave low scores to the device. In the future, I would add a “sensitivity” test prior to tactile sound testing.
Age is a factor in the results, as expected. So is gender. However, while being younger appears to make people more sensitive to tactile sound, older age and gender are not always negative factors. The lowest scores were given by two male subjects under 60 who showed poor sensitivity. However, other males showed strong results and provided positive feedback.
An important lesson from this experiment is each individual’s hearing ability is different and each individual’s perception of sound, music and tactile experience is unique. The 1-10 rating system was helpful to standardize things, especially because subjects had many chances to evaluate their own ratings and experience since each tested body part was evaluated at least 6 times by each subject and always out of 10.
Seeking the optimal position of the K-MAD on the subjects’ bodies also helped create a set standard since every subject’s final rating is based on the most effective arrangement of the K-MAD on their body.
One other element that was standard was that all the subjects were listening at their ideal levels since they were all asked to wear or set their hearing device to their daily life setting, their “normal” setting.