Glossary beginning with N

N

natural frequency

"The frequency of a free vibration... not the same as resonance frequency" [1]

---

References

1. Broughton WB. Glossarial Index. In: Acoustic Behavior of Animals. Acoustic Behavior of Animals. Elsevier; 1963.

natural period

"period of a free vibration." [1]

---

References

1. Broughton WB. Glossarial Index. In: Acoustic Behavior of Animals. Acoustic Behavior of Animals. Elsevier; 1963.

near field

"The area less than one wavelength from a sound source. In this area pressure and particle velocity are out of phase and sound measurements are unpredictable." [1]

---

References

1. Ewing AW. Arthropod Bioacoustics: Neurobiology and Behaviour. Ithaca, New York: Comstock; 1989.

node

"a point, line or surface of an interefrence pattern at which the amplitude of the sound pressure (pressure node) or particle velocity (velocity node) is zero (ir, in practice, a minimum)." [1]

---

References

1. Broughton WB. Glossarial Index. In: Acoustic Behavior of Animals. Acoustic Behavior of Animals. Elsevier; 1963.

noise

"(1) sound which is undesired by the recipient. Undesired electrical disturbance in a transmission channel or device may also be termed noise, in which case the qualififcation electrical should be included unless it is self evident.

(2) Sound without regularities, confused sum of many unrelated sounds heard together.

(3)"white noise", the extreme case of (2), in which the sound spectrum contains all frequencies in more or less equal measure." [1]

---

References

1. Broughton WB. Glossarial Index. In: Acoustic Behavior of Animals. Acoustic Behavior of Animals. Elsevier; 1963.

noise pollution

"Noise pollution refers to the elevation of natural ambient noise levels due to sound-generating human activities, which may have detrimental consequences for humans and animals alike..." [1]

---

References

1. Slabbekoorn H. Noise pollution. 2019. Available at: https://linkinghub.elsevier.com/retrieve/pii/S0960982219308632.

See also: anthropophony

normal mode

"a characteristic distribution of vibration amplitudes, among the parts of a system each part of which is vibrating freely at the same frequency. Complex free vibrations are combinations of these simple normal modes." [1]

---

References

1. Broughton WB. Glossarial Index. In: Acoustic Behavior of Animals. Acoustic Behavior of Animals. Elsevier; 1963.

Normal song

See: Calling song

note

"a. a conventional sign for a tone which indicates its pitch and duration;

b. the tone itself.

N.B. The tone may be, and usually is, complex." [1]

---

References

1. Broughton WB. Glossarial Index. In: Acoustic Behavior of Animals. Acoustic Behavior of Animals. Elsevier; 1963.

nycthemeral

"rhythym with a 24-hour repetition period. The best term of several." [1]

---

References

1. Broughton WB. Glossarial Index. In: Acoustic Behavior of Animals. Acoustic Behavior of Animals. Elsevier; 1963.

Synonyms: nycthemeral rhythm

Go to top