LATENT REFERENCES / TAG2
Pink Noise (1/f Noise)
Original title: ピンクノイズ（1/fノイズ）
This reference note belongs to Tag2 in Latent References, an archive curated by Keigo Yoshida. Its archive region is Stax Records. The note preserves its source text and links so that readers can trace the material behind the 3D map.
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- Tag2
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- Stax Records
Archived reference note
English translation of the archived note. JP shows the original text. Source links and literal code are retained; the translation does not update or independently verify the source claims.
The frequency spectrum of pink noise is approximately a straight line on a log-log graph, with equal power in frequency ranges of equal width on that graph. In other words, the power in the frequency range from 40 to 60 Hz equals that in the range from 4000 to 6000 Hz. Human hearing actually has similar characteristics: whatever the original frequency, doubling it is perceived as rising 1 octave (changes of 40–60 Hz and 4000–6000 Hz are perceived similarly). Pink noise, with equal power per octave, is therefore often used as a reference signal in acoustic engineering. In terms of spectral density, it shows a decline relative to white noise of 3dB per 1 octave (10dB per 10-fold frequency increase) (density is proportional to 1/f). Pink noise is consequently also called 1/f (1 over f) noise.
https://scrapbox.io/files/648b1c83c8e35e001b60315c.png
ピンクノイズ周波数スペクトルは両対数グラフで表すとほぼ直線になり、そのグラフ上の同じ幅の周波数範囲でパワーが等しくなる。つまり、40 から 60 Hz の周波数範囲のパワーは、4000 から 6000 Hz の周波数範囲のパワーと等しい。実際ヒトの耳も似たような特性があり、元の周波数がどういう値であれ、周波数が倍になると1オクターヴ上がったと感じる（40–60 Hz の変化と 4000–6000 Hz の変化は同じように感じる）。そこでオクターヴあたりのパワーが等しいピンクノイズは音響工学における基準信号として使われることが多い。スペクトル密度で言えば、ホワイトノイズに対して1オクターヴあたり3dB（周波数10倍あたり10dB）の降下を示す（密度は 1/f に比例）。そのためピンクノイズを 1/f（f分の1）ノイズとも呼ぶ。
https://scrapbox.io/files/648b1c83c8e35e001b60315c.png
Source updated 2023-06-15 · Snapshot 2026-10-08
Source links and calculated neighbors
Cosine values measure shared lexical features, not truth, agreement or identical meaning. Original reference links are labeled separately.
- Purple Noise (Violet Noise)Computed lexical cosine similarity 0.338 · shared title, text, tags and references
- White NoiseComputed lexical cosine similarity 0.260 · shared title, text, tags and references
- Blue Noise (Azure Noise)Computed lexical cosine similarity 0.230 · shared title, text, tags and references
- Grey NoiseComputed lexical cosine similarity 0.223 · shared title, text, tags and references
- Colored NoiseComputed lexical cosine similarity 0.179 · shared title, text, tags and references
- Brown NoiseComputed lexical cosine similarity 0.165 · shared title, text, tags and references
- Spectralism and IRCAMComputed lexical cosine similarity 0.110 · shared title, text, tags and references
- Snow NoiseComputed lexical cosine similarity 0.108 · shared title, text, tags and references