Theremin affecting hearing?

Also - Beware.. I suspect that the actual 'loudness' you hear will be a function of harmonic content (sounds rich in harmonics sound louder) so, with an instrument like the Theremin which produces (mainly) sounds with low harmonic content, it is likely that one may compensate by turning the volume levels up!

The problem with this is that the amplitude may be high even if the percieved volume is not particularly high - and this could cause you hearing damage.

I worked as a design engineer in a large London hospital + School of medicine (Royal free), and for one of the research projects I produced low distortion sine oscillators driving high quality headphones, for purpose of sweeping the audio spectrum while scanning neurological signals - One thing I noticed was that, at a safe level, the volume I heard was extremely low (I am used to putting the cans on and cranking my music up loud!) I was worried by this and got my hearing tested while in the lab, and it was fine.

Maybe it's a bit like when you look out the window when it's raining and then when you look away you get little streams in your vision?

Yes, that IS the best I can do!

I dont think there is reason for paranoia over this - just perhaps a little extra care.. If one makes the tone as 'rough' (highest harmonic content) as possible, this should make the sound 'louder', reduce the risk of high amplitude overload, and reduce the neurological effects of long exposure to sine waves (which can cause fatigue and further temporary reduction in the level of the sound heard).. Alternatively, lots of fast vibrato may help to make the sound appear louder.

"Maybe it's a bit like when you look out the window when it's raining and then when you look away you get little streams in your vision?"

Sorry - I dont know that one! Perhaps because I wear glasses or dont look as well as I listen... But I think the visual neurological signals tend to be far more 'processed' than audio signals.. The eye/brain has difficulty with any stimuli occurring more than 30Hz - and much of what we 'see' is probably a complex composite and not 'reality' .. Audio processing is far faster - exact mechanisms not well understood - but we can hear distortion on a 5kHz signal easily, which means we must be able to update a 'snapshot' of audio at least 10,000 times a second - Altenatively, the brain has a real-time spectrum analyser capable of this rapid processing... As far as I know, audio processing is the fastest activity undertaken by the brain.

I practice 8 to 10 hours a day, and I do use a Rockmore style vibrato quite a bit. So far, I think I've been lucky not to have suffered any noticable affects from prolonged exposure to the theremin, but then I don't play as loud as most guitarists would.

The comparison of latent image after affects of the eyes after staring at certain paterns over time, to possible latent audio after affects is quite interesting. I'm sure there's a paper in that somewhere.

I wonder if there is any relation between the described effect and tinitis (ringin in the ears)?