Hi! What an awesome project, and such a lovely source of inspiration. Making something for my (late) mother has been a major influence on me continuing to dig deeper in search of the right sound.
A few things come to mind. The first is a little goofy, but I wanted to drop this article quickly: The moment Lou Reed and Laurie Anderson staged a concert for dogs
I don’t know a ton about all of this, but I think Hitsware makes a good point about infrasonic pulses, especially due to the fact that lower frequencies seem to be much easier to feel; I’m sure most can recall bass thumping through their whole body at a loud show, or the way your chair will rumble in a cinema during an action movie.
Honestly I’ve gone a bit down the rabbit hole in writing this, and here’s another article my curiosity led me to: Bass: the Physical Sensation of Sound | Audioholics
I’d like to call out a line from it because… wow:
While one test found that none of the participants could sense any vibration at 1 and 2 Hz even at 144 dB, one effect that might be possible for humans at this extremely low frequency and extremely high amplitude is artificial respiration. One Air Force study found decreased respiration in anesthetized animals subjected to frequencies from 0.5 Hz to 8 Hz at sound pressure levels above 166 dB, and at 171 to 173, independent respiration ceased for large dogs, with their chest being virtually motionless below 1 Hz. The animals were not suffocating; what was occurring was the pressure waves were so large that air molecules were being exchanged between the ambient air and the lungs of the dog, so, in a manner of speaking, the sound waves were breathing for the dog.
Probably a reckless thing to try and implement (especially if she’s in an apartment, ha!), but… this is really making me think we wildly underestimate the power of music if considering it as a purely auditory experience. That really is a cool article - it has several diagrams showing where listeners experienced resonance with various frequencies in their bodies. I almost imagine something like a sonic massage; long, bending notes that wash through whoever is perceiving the music… far out.
OK so, let me throw a few ideas out there.
Rather than buzzers, my instinct would be to route various frequencies into different types of speakers, located in different places. For example, what if you panned all of your deep frequencies to the left, and you just hooked a subwoofer up to the left channel, then perhaps provided a bluetooth speaker (which would be your ‘right’ channel) which could be held by whoever is experiencing the music?
Since we’re used to feeling ‘more precisely’ with our hands and fingertips, the more rapid vibrations would be channeled into the hands, and the lower, rolling bass would bounce all around the room. Whoever was experiencing your composition could also try holding the speaker in different ways, maybe pressing it into their chest or below their chin? There’s something really interesting to me about the idea that one might send all of these waves around their body without hearing them. It’s a musical experience folks who can hear could never have!
Another curiosity might be… what might occur when someone who couldn’t hear perceived slightly varying frequencies similar to binaural beats, but rather than through the ears… through the hands or feet?!
Also, maybe you could make use of the RPi as an input device rather than an output device? For example, maybe there’s a way to connect something like a smart watch, and have the music interact with the observer’s pulse.
Last, I think Hydra would be an incredible complement to this sort of thing - it’s a video synth which can take midi/osc inputs. I have seen some awesome work which includes text, which could evoke deep and powerful musical memories in a person by displaying the lyrics of songs they once heard. The expressive capacity in hydra is phenomenal - shapes, colors, tempo… it’s all there. And if you could find a way to link inputs from the observer, it could be a very very unique and remarkable experience.
I love this idea and hope something in this stream of consciousness is a useful sourdough starter for you.
Cheers and best of luck!