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[null,"Headphone Power Calculator"]
[null,"By Rob Robinette",null,"V1.6"]
[null,"Enter Values In Yellow"]
[null,"Headphone Impedance ",32," ohms Ω"]
[null,"Enter either Headphone Sensitivity: dB/mW OR dB/V"]
[null,"dB/mW Headphone Sensitivity ",89," dB/mW  (dBSPL at 1 milliwatt)"]
[null,"OR dB/V Headphone Sensitivity ",0," dB/V  (dBSPL at 1Vrms)"]
[]
[null,"Calculated Headphone Sensitivity ",{"v":103.94850021680094,"d":"103.95"}," dB/V  (dBSPL at 1Vrms)"]
[null,"Power ",31.25," milliwatts at 1Vrms"]
[null,"Current ",31.25," milliamps rms at 1Vrms"]
[]
[null,"What's Required to Reach a Loudness Level"]
[null,"Target Headphone Loudness ",{"v":95,"d":"95.0"}," dB Sound Pressure Level"]
[null,"Power Required ",{"v":3.9810717055349754,"d":"3.98"}," milliwatts"]
[null,"Voltage Required ",{"v":0.356923373537121,"d":"0.3569"}," Volts RMS"]
[null,"Current Required ",{"v":11.153855423035031,"d":"11.15"}," milliamps rms"]
[]
[null,"How Loud Will an Amp Drive Your Headphones"]
[null,"Amplifier Vrms Rating ",{"v":0.357,"d":"0.3570"}," Volts RMS"]
[null,"Amplifier Power ",{"v":3.9827812499999995,"d":"3.98"}," milliwatts"]
[null,"Amplifier Current ",{"v":11.15625,"d":"11.16"}," milliamps rms"]
[null,"Headphone Loudness ",{"v":95.0018645390448,"d":"95.00"}," dB Sound Pressure Level"]
[{"$nulls":3}," 120 dbSPL is threshold of pain"]
[null,"Instructions"]
[null,"Fill in the yellow boxes:"]
[null,"Enter Headphone Impedance"]
[null,"Enter Headphone Sensitivity in dB/mW OR dB/V"]
[null,"     If dB/mW is entered then dB/V will be calculated and vice versa"]
[null,"For the “Target Loudness” calculation enter your desired loudness in dBSPL"]
[null,"For the “How Loud” calculation enter the amplifier's rated Vrms."]
[null,"dB = decibel"]
[null,"SPL = Sound Pressure Level"]
[null,"RMS = root-mean-square"]
[null,"dB/mW = decibel Sound Pressure Level at 1 milliwatt"]
[null,"dB/V = decibel Sound Pressure Level at 1 volt root-mean-square"]
[null,"Vrms = volt root-mean-square"]
[]
[null,"Example: My HE-500 headphones are rated at 38 ohms impedance"]
[null,"    and 89 dB/mW sensitivity (enter in dB/mW box). The spreadsheet"]
[null,"    calculates 103.2 dB/V sensitivity, 26.3 milliwatts and milliamps at 1Vrms."]
[null,"    To reach a Target Loudness of 95 dBSPL an amplifier will have to"]
[null,"    provide 3.98 milliwatts of power, 0.389 volts rms and 10.24 milliamps."]
[null,"    When I enter my Schiit Mjolnir's Vrms rating of 16 Vrms into 32 ohms"]
[null,"    the spreadsheet calculates 8000 milliwatts (8 watts) and"]
[null,"    headphone loudness of 128.0 dBSPL."]