Kalkulator Audio

Tontechnika provides a series of audio calculators that sound system designers, engineers, and technicians frequently need to access, such as determining amplifier power requirements, converting between dBu and dBV or volts, or estimating the loss in sound pressure level with an increase in distance. All of the easy-to-use calculation tools are accessible by clicking on the icons below.

 

Penjelasan

Volts, dBV, and dBu are three units describing voltage levels that are used interchangeably in professional audio based on the point of reference. This audio tools provides a quick and convenient means to convert between them. dBV refers to a voltage magnitude referenced to 1 volt, while dBu is referenced to 0.775 volts.

Variabel

  • dBV
  • dBu
  • Volts

Rumus

  • dBV = dBu – 2.21
  • Volts = 10(dBu / 20) x 0.775
  • dBu = dBV + 2.21
  • Volts = 10(dBV/20)
  • dBu = 20 log (Volts/0.775)
  • dBV = 20 log (Volts)

 

Penjelasan

A change in voltage, from V1 to V2 can be expressed as a ratio in decibels with the equation RV = 20*log(V2 / V1). A doubling in the voltage level translates to a power ratio of 6 dB. Similarly, halving the power equals a -6 dB voltage ratio. This calculator can also be used to express differences between two distances or pressures.

Rumus

dB = 20 log (V2/V1)

 
This calculation will give you the ratio, in decibels, between two power values. For example, you can calculate the difference in dB between two amplifiers with different power output specifications.

Enter any two values and press “Calculate” for the remaining value.

Equation used to calculate the data:
dB = 10 * Log (Pout / Pin)

What It Is
A change in power, from P1 to P2 can be expressed as a ratio in decibels with the equation dB = 10*log(P2/ P1) . A doubling in the power level translates to a power ratio of 3 dB. Similarly, halving the power equals a -3 dB power ratio.

Essential Formulas

  • dB = 10 log (P2/P1)

 

What It Is
Sound system designers frequently want to know much amplifier power will be needed to deliver adequate sound pressure levels for the application. This can be determined based on the desired listener distance from the speaker, the desired sound pressure level of the audio at this distance, and the loudspeaker’s published sensitivity rating to provide the reference acoustical output at 1 watt at 1 meter. For Extron speakers, use the dropdown box and select the desired Extron speaker to automatically load its sensitivity into the calculator field. Additional headroom should be added for the amplifier, for example, 10 dB, to account for variability in program audio levels.

This audio tool calculates the acoustical attenuation from the reference location of 1 meter (3.28 feet) to the listener, and then applies this, together with the sensitivity rating and amplifier headroom, to determine the necessary output power from the amplifier.

Rumus Terkait

  • APR = 10((LP + H – LS + 20 log (D2/ DR))/10)

Where:

  • APR = amplifier required power
  • LP = required SPL at listener
  • H = desired amplifier headroom
  • LS = loudspeaker sensitivity at 1 watt and 1 meter
  • D2 = distance to farthest listener
  • DR = 1 meter or 3.28 feet reference distance

 

What It Is

Sound pressure level – SPL decreases 6.02 dB as a listener’s distance doubles from the sound source. This number is commonly rounded down to 6 dB. The opposite is true as the listener halves the distance to the source, so that the SPL decreases or increases by 6 dB with every distance doubling or halving, respectively. The Inverse Square Law is used to calculate the change in SPL with distance, and is useful in predicting the sound pressure level a listener will experience as speaker placement and sound levels are considered.

Sound pressure level showning inverse square law

Essential Formulas

  • LN = LR – 20 log (DN/DR)
  • DR = reference distance
  • DN = new distance
  • LR = SPL at reference distance
  • LN = SPL at new distance