|Listening Loudness||Voltage Needed||Current Needed||Power Needed|
|Safe||85 dB SPL||17782.79 Vrms||0 mA||0 mW|
|Moderate||100 dB SPL||100000 Vrms||0 mA||0 mW|
|Fairly Loud||110 dB SPL||316227.77 Vrms||0 mA||0 mW|
|Very Loud||115 dB SPL||562341.33 Vrms||0 mA||0 mW|
|Painful||120 dB SPL||1000000 Vrms||0 mA||0 mW|
When trying to determine if your player or headphone amplifier is capable of properly driving your favorite cans, there are a few things you should keep in mind. First, power isn't just power - it's a function of both voltage and current. To properly drive your headphones, you need sufficient amounts of both. The general rule of thumb is that higher impedance headphones need more voltage and lower impedance headphones need more current.
So when looking for a suitable headphone amp for your high impedance headphones, it's all about the voltage, right? Wrong.
Only a few volts are needed to make a high impedance headphone painstakingly loud - especially in the midrange and treble ranges. But, unless you hate bass, it's important that your amp provide the proper amount of current to ensure your headphones’ voice coil moves enough (or has enough displacement) to produce deep bass too! The secret to fast, detailed and well-controlled bass is lots of current, not voltage. So what this comes down to is this… it’s not about how much raw power you have, it’s about how much of the right kind of power you have that matters.