I wonder if one can create a similar auditory transfer function that is attuned to a specific voice.... basically evolve a sound cavity of specific shape
You could have a large capture cavity initialy that has various rods of materials that would sympathise with certain frequency ranges. Those rods run into their own chamber's - seperating the frequencies.
Problem is with voice, it's the cadence, content and variations in the tones that help discern an individual. For that you need to factor in a variable amount of past data as you can't just take a snapshot - think taking a picture of a single frame in a movie and knowing what the entire movie is about.
However, you could make something that needs a certain set of frequencies, so with that something that could identify males or females by the sound of the voice and the general rule of male voices being lower in frequency. That would be a start. Though even that simple task, you start to see exceptions.
But if you can flowchart it and have ways to handle the logic, who knows what is possible and impossible.
Probably a cheat, but a piezo disc setup would give you zero power audio capture and with others to power basic processing, you would be able to do something, though may find yourself shouting during testing, though a capture cone to focus the audio onto the piezo would help immensely. Though I'd seriously have to sit down and work out what surface area of pezios and vibration levels and as such power you could produce. Though could mitigate that with some larger capacitors to capture all the passive sound and low level power the piezo's will capture/produce during the day. Triggering processor to check for your keyword and instigate an action.
