ouestion two on frequency.

[justoleme]

What is the highest frequency ? is there a limit by the laws of physics? Or does it go back to zero?because of the limitation of time?

[mastodon]

Highest Frequency to Be Heard by Human
From: ETL Acoustics Group

It had been believed that the audible frequency range of human would be between 20Hz and 20000Hz. Several recent researches, however, had argued about subjective difference between sounds sampled at 44.1kHz and 96kHz. What can make inaudible ultrasounds audible is not known.

Ultrasonic tone is not audible when it is presented alone. If it becomes audible when presented in a complex of sounds, possible explanation may be as follows,
[*] because of parametric effects of the air [*] because of non-linear activities of auditory system [*] because of non-linearity distortions of equipments (probably loudspeakers).

When an ultrasonic tone modulated by audible sounds is traveling through the air and its level is sufficiently intense, it is demodulated and the audible sounds are produced. It is called parametric effect.

When more than two different tones are presented, difference tones and combination tones can be perceived due to non-linear activities in the auditory system. It is not known, however, if ultrasounds can induce non-linear activities of the auditory system.

When more than two different tones are delivered through one loudspeaker, it may produce intermodulation distortions even if the primary tones are ultrasounds. Linearity of even the high-class loudspeakers is not larger than 70dB.

The following experiments were designed so that the audibility of an ultrasonic component in a complex of sounds would be investigated. Influence caused by intermodulation distortions of loudspeakers was also examined.
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as for highest possible frequency, the highest frequency to be resolved rests on the precision and capability of the lab equipment of today.

[justoleme]

That was really good..As i remember we were speaking of instruments for music ,so that would be audible frequencies..so i can understand how this answer came to be..But let us go on up the scale untill it ends way above microwave frequencies.OR does it end?Maybe at one .00001 wave length?