fullseye

weighting_response — ACOUSTICS level op

使い方

The A / C / Z frequency-weighting curve, in dB, at the given frequencies.

Computed from the four pole frequencies that define the networks and normalised so that the response at 1 kHz is exactly 0 dB by construction — the curve is divided by its own value at 1 kHz rather than having a published offset constant added to it. That is why the tests can assert equality at 1 kHz to 0.0 rather than to a tolerance, and why no standard’s table of attenuations appears anywhere in this repository.

The response depends on f only through f**2, so it is an even function and negative frequencies are evaluated at |f| — that is the definition, not a repair. f = 0 has zero response (both curves have a zero at DC) and is reported as floor_db rather than -inf.

Measured (computed, then printed — these are outputs, not transcriptions):

======== ========= ========= f (Hz) A (dB) C (dB) ======== ========= ========= 10 -70.4304 -14.3300 31.5 -39.5250 -3.0305 100 -19.1428 -0.2996 1000 0.0000 0.0000 4000 0.9633 -0.8260 10000 -2.4918 -4.4055 20000 -9.3469 -11.2786 ======== ========= =========

A(1000) and C(1000) are exactly 0.0 — the Python float, not a rounding — because of the construction. The low-frequency asymptote is a closed form and is asserted in the tests: A falls at exactly 80 dB/decade as f -> 0 (f**4 over three constants) and C at exactly 40 dB/decade (f**2). Measured between 0.001 and 0.01 Hz with the floor lowered out of the way: 79.999998 and 39.999998 dB/decade.

That last caveat is real and is why the floor is an argument: with the default floor_db = -200 the A curve reaches the floor below about 0.35 Hz (unfloored, A(0.1) = -228.55 dB), so the asymptote measured against the default floor comes out as 0.0 dB/decade between 0.01 and 0.1 Hz — a clamp, correctly reported, that would look like a bug if the floor were not visible.

Returns a float64 array the same shape as freqs.

Raises ValueError: a non-1-D / non-finite / complex / masked freqs, an unknown kind.

詳しい使い方ガイド

参考(サンプルデータ・文献)

実行できる例(この op を実際に呼ぶ検証済みサンプル)

型が繋がる次の op(signal を入力に取れる)

stft · envelope_spectrum · spectral_kurtosis · cepstrum · angular_resample · order_spectrum · octave_spectrum · apply_weighting

同カテゴリ(level)

octave_bands · octave_spectrum · apply_weighting · equivalent_level · percentile_level


Provenance: acoustics.py — ACOUSTICS operator registry. この per-op ノートは tools/opdocs.py md が自動生成(手編集しない)。

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.