Conversion: neper to decibel bel napier Np dB pseudo unit - sengpielaudio
Deutsche Version UK-flag s/w - sengpielaudio D-flag - sengpielaudio
Conversion ratios of gain and loss
Level with the pseudo units:
neper (Np), decibel (dB), and bel
Enter the known pseudo unit at the appropriate line.
The other boxes will show the conversions.
You don't need a calculate bar.

Bel B
Decibel dB
Neper Np

Notice: Do not re-enter the exact number of an answer.

Neper Decibel scale - sengpielaudio

The conversion scale of the pseudo units decibel (dB) and neper (Np)

Neper is a unit used to express ratios, such as gain, loss, and relative values.
Note 1: The neper is analogous to the decibel, except that the Naperian base
2.718281828 is used in computing the ratio in nepers.
Note 2: The value in nepers is given by Np = ln (x1 / x2), where x1 and x2 are the
values of interest, and ln is the natural logarithm, i.e., logarithm to the base e.
Note 3: One neper Np ≡ 20 / (ln10) = 8.685889638 dB.
Note 4: The neper is often used to express voltage and current ratios, whereas
the decibel is also used to express power ratios.
Note 5: Like the decibel dB, the Np is a dimensionless unit.
Note 6: The ITU recognizes both units.
The other likely candidate for the base of the log is e = 2.718281828, which has nice properties in equations, etc., and just seems to fall out of all sorts of natural phenomena - unlike 10, which is popular because we have 10 fingers. Using e as your base leads to a less common unit called the neper (Np). Neper is the Latin form of Napier, the guy who popularized the use of logs for computation
(viz. Napier's bones). Nepers are used with voltage (or magnitude) ratios, so
watch out when converting back and forth between nepers and dB. Decibel
and neper have a fixed linear ratio to each other.

1 Np ≡ 20 / ln(10) = 8.685889638 dB
1 dB ≡ ln(10) / 20 Np = 0.115129255 Np      

1 Np = (20 lg e) dB ≈ 8.6859 dB              
1 dB = (0.05 ln 10) Np ≈ 0.11513 Np                

Conversion from dB to Np:
Np value ≡ dB value × ln (10) / 20 = dB value × 0.115129255

Conversion from Np to dB:
dB value ≡ Np value × 20 / ln (10) = Np value × 8.685889638
The voltage level is     Formel Neper dB
x2 is the reference value.

John Napier of Merchiston (1550 - 4 April 1617) - also signed as Neper, Nepair - named Marvellous Merchiston, was a Scottish landowner known as a mathematician, physicist, astronomer and astrologer.

Conversion: bel, decibel, centibel, and millibel

How to calculate decibels? - The dB calculator - a valuable tool
Converting number relations (ratio) to dB level
Impedance bridging or Voltage bridging Zout < Zin
Table: Relative level - decibel chart and dB conversion calculator
Conversion dBu dBV to Voltage V
Conversion: Voltage V to Level, dB, dBu, dBV, and power level dBm
Conversion of dB (decibel) to bel

The Bel is no physical size, but means only that it is the value of the logarithm of a ratio. Sound pressure level (SPL) is the ratio of sound pressure in comparison to a reference sound pressure, the threshold of hearing (0.00002 Pa = 20 µPa).
back zurück Search Engine weiter home Start