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The distance between the frequencies 20 Hz and 40 Hz is 1 octave. An amplitude of 52 dB at 4 kHz decreases as frequency increases at −2 dB/oct. What is the amplitude at 13 kHz?
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An amplifier or filter may be stated to have a frequency response of ±6 dB per octave over a particular frequency range, which signifies that the power gain changes by ±6
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174:(4) ≈ 6 decibels per octave, corresponds to an amplitude gain proportional to frequency, which is equivalent to ±20 dB per
343:{\displaystyle {\text{Mag}}_{13{\text{ kHz}}}=52{\text{ dB}}+(1.7{\text{ oct}}\times -2{\text{ dB/oct}})=48.6{\text{ dB}}.\,}
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170:(a factor of 4 in power), when the frequency changes by a factor of 2. This slope, or more precisely 10 log
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178:(factor of 10 amplitude gain change for a factor of 10 frequency change). This would be a
156:{\displaystyle {\text{number of octaves}}=\log _{2}\left({\frac {f_{2}}{f_{1}}}\right)}
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is a doubling in frequency. Specification in terms of octaves is therefore common in
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249:{\displaystyle {\text{number of octaves}}=\log _{2}\left({\frac {13}{4}}\right)=1.7}
396:; the association of the word with doubling is solely a matter of customary usage.
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A frequency ratio expressed in octaves is the base-2
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Computer
Controlled Systems: Theory and Applications
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Relative unit corresponding to doubling of frequency
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418:The Control Handbook: Control System Fundamentals
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416:Levine, William S. (2010).
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479:Audio electronics
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102:number of octaves
78:Ratios and slopes
66:used to describe
53:audio electronics
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88:binary logarithm
72:frequency ratios
33:logarithmic unit
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388:The prefix
365:Octave band
41:frequencies
21:electronics
468:Categories
404:References
62:, it is a
474:Acoustics
312:−
309:×
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278: kHz
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84:logarithm
47:where an
27:(symbol:
354:See also
333: dB
291: dB
168:decibels
39:between
186:Example
31:) is a
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360:Octave
176:decade
60:decade
49:octave
37:ratios
25:octave
390:octa-
376:Notes
23:, an
451:ISBN
430:ISBN
422:ISBN
329:48.6
64:unit
55:.
35:for
301:1.7
269:Mag
244:1.7
211:log
110:log
70:or
29:oct
19:In
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86:(
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