How to Use
This calculator estimates the maximum headphone loudness in dB SPL when plugged into a motherboard, given the specifications/settings of the motherboard and headphones. To find headphone loudness for an amplifier in general, see the headphone loudness calculator.
System Specs
Select your audio codec from the list. You can usually find your codec on the motherboard manufacturer’s specifications page. This will determine the maximum output voltage. Note that since Realtek datasheets are generally not publicly available and multiple variations of these codecs exist, the actual output voltages may vary somewhat from the numbers used here.
Enter the output impedance of your motherboard. This value is typically not published by motherboard manufacturers. If you are not sure what your motherboard’s output impedance is, enter 75Ω. Most motherboards use a value around 75Ω, as this is the value used in older Realtek example circuits.
Enter the Windows volume you want the calculation to be performed for. Don’t be alarmed if some values don’t change the calculator output at all; not all Windows volume levels are different from their neighbors. If you want to see the maximum loudness for a headphone on your system, use 100. See the article on digital volume tapers for more details about Windows volume.
Headphone Specs
Enter the sensitivity/efficiency of your headphones, which can usually be found on the headphone’s product page, but can also be sourced from third-party measurements. Adjust the units depending on whether the sensitivity is specified in dB at 1 mW or dB at 1 mV. If no units are given, try searching third-party measurements. If the value is given in another format, for instance “94dB at 7mV” or “107dB at 30mW”, you may need to use the headphone sensitivity calculator to find the 1mW or 1mV sensitivity. If all else fails, these values are normally given in dB/mW.
Enter the impedance of your headphones, which can usually be found on the headphone’s product page. Third-party measurements are usually more accurate. If possible, find a frequency vs. impedance graph. If the impedance varies significantly over the frequency range, consider using the output impedance amplitude calculator to see if your headphone’s sound signature will be altered by your motherboard. The attenuation value from that calculator is already baked in to this calculator’s calculation.
Output
The calculator will output a value in dB SPL. This is the maximum loudness of your headphone (using a sine test tone), when played using your system specs. Typically music averages about 15dB quieter than the maximum volume (it is composed of a variety of different sounds, after all), so if your goal is to find the average listening volume at those settings, subtract 15dB or so from the calculator’s output. This value can vary based on genre and song; for instance, pop will usually be closer to 10dB, while classical may be closer to 20dB.
Examples
Sample 1: Finding Safe Listening Volumes
Note: This is not medical advice. This calculator is for informational purposes only. If you are concerned about hearing safety, please talk to a medical professional.
Say you have a Razer Kraken Pro v2 headset and are concerned about hearing damage. You want to know what volume settings are safe to listen at in Windows.
You have a fancy new gaming motherboard with an ALC1220 audio codec, so you select “ALC1220” chipset and “75Ω” output impedance. Razer specs the Kraken Pro v2 at 32Ω, 118dB/mW, so you enter these as the impedance and sensitivity values.
You normally listen to music at around 40/100 Windows volume, so you enter this value into the calculator and hit Calculate.
The calculator returns 115dBSPL output. Since you are concerned about average music levels for safe listening, you subtract 15dB from the output to get 100dBSPL. This is 15dB higher than OSHA’s minimum dangerous sound exposure of 85dB, and 30dB higher than the ~70dB level typically considered safe indefinitely. You might want to limit yourself to volume settings at or below 10, which corresponds to 96dB peak or 81dB average, in order to avoid hearing loss.
Sample 2: Predicting Headphone Loudness
Say you have a HyperX Cloud Headset, which you are happy about the volume level of, and were thinking about buying nicer closed-back headphones. You were considering Beyerdynamic DT1770 Pro (250Ω), but are concerned that your motherboard might not be able to drive it loud enough since it’s a high impedance headphone. Since you’ve been told that low impedance headphones are easier to drive, you’re now also considering the DCA Aeon Closed X, a 12.5Ω headphone.
First, find out how loud your current headset gets. The Cloud is specified at 98dB/mW Sensitivity, 60Ω impedance, so enter these values into the “Headphone Specs” portion of the calculator. You enter ALC897 as the audio codec and keep the default 75Ω output impedance value.
Entering these values and using 100/100 Windows volume outputs 104.76dBSPL. If the other headphones can reach that value on your motherboard, then they will most likely be loud enough for you.
The Aeon is rated 12.5Ω, 91dB/mW. Plugging in these values, the Aeon can reach 94.71dBSPL from your motherboard.
The DT1770 is rated 250Ω, 102dB/mW. Plugging in these values, the DT1770 can reach 107.33dBSPL from your motherboard.
Based on this information, the Aeon will likely be too quiet, while the DT1770 will be loud enough. Preferred listening level and sensitivity have a much larger effect on whether a headphone will be loud enough than impedance does.