Convert Decinepers to Millibels
Convert Decinepers (dNp) to Millibels (mB) instantly and accurately.
Conversion Formula
mB = dNp × 86.85889638
About Decinepers
The decineper (dNp) is one-tenth of a neper (1 dNp = 0.1 Np ≈ 0.8686 dB). This range directly overlaps the human auditory just-noticeable difference (JND): the typical JND for loudness at a moderate steady tone is ≈ 0.2–1 dB = 0.23–1.15 dNp for trained listeners (ISO 532B; Moore, 2012). In wave propagation, attenuation constants of 1–10 dNp/m (0.87–8.69 dB/m) are typical of semi-anechoic room wedge absorption and microwave absorber material characterisation. In electromagnetic propagation through seawater at 10 kHz, the skin depth is ≈ 2.7 m giving α ≈ 3.7 dNp/m; at 1 MHz, δ ≈ 0.27 m giving α ≈ 37 dNp/m. In control systems, the real part σ (Np/s) of the complex frequency s = σ + jω governs exponential decay of transients; the decineper range of σ corresponds to mildly underdamped oscillators. 1 dNp = 0.1 Np ≈ 0.8686 dB ≈ 0.08686 B.
About Millibels
The millibel (mB) is one-thousandth of a bel (1 mB = 10⁻³ B = 0.01 dB), the finest routine subdivision of the bel family in widespread practical use. The AES17-2015 standard for digital audio converter measurement requires frequency response flatness within ±0.01 dB (±1 mB) across 10 Hz–20 kHz for a reference-quality interface. Audiometer calibration (IEC 60645-1, ANSI S3.6) specifies attenuator step accuracy to ±0.1 dB (10 mB) for research-grade psychoacoustic instruments. Modern audio codec chips (ESS Sabre ES9038PRO) specify passband ripple to 0.01 dB = 1 mB. In broadcast loudness metering (EBU R128, ITU-R BS.1770), integrated loudness is calculated at 0.1 LU = 10 mB resolution. IEC 61672-1 Class 1 sound level meters achieve frequency response flatness within ±0.7 dB (70 mB) from 31.5 Hz to 8 kHz. 1 mB = 0.001 B = 0.01 dB ≈ 1.151 × 10⁻³ Np.
Quick Reference Table
| Decinepers (dNp) | Millibels (mB) |
|---|---|
| 1 dNp | 86.8589 mB |
| 2 dNp | 173.718 mB |
| 5 dNp | 434.294 mB |
| 10 dNp | 868.589 mB |
| 25 dNp | 2171.47 mB |
| 50 dNp | 4342.94 mB |
| 100 dNp | 8685.89 mB |