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I need 100 custom polyphonic ringtones for seniors according to Psychoacoustics
Ringtones has to be created having elder people in mind: in particular they must follow guidance of limits of perception and frequencies to allow best chances to be heard by senior people.
Growing old means hearing impairment: aging means hearing loss. In particular people are not able to hear some frequencies.
These 100 polyphonic ringtones will be put as free download on a free site: they have to be created to get the maximum chance to be heard by older people.