HiFiMAN is well aware that the power requirements of these headphones is a limitation for some customers, and with this thought firmly in mind they set out to create a model that combined elements of the HE-5LE and HE-6 designs, yet that would be easier to drive than either of them. The rated sensitivity of the HE-500 is 89 dB/mW, a figure that is 1.5 dB higher than the HE-5LE’s rating and a whopping 5.5 dB higher than the HE-6’s. While it might not seem very significant, that step up in sensitivity makes a big difference in terms of real-world usability and amplifier flexibility, although the HE-500 still doesn’t qualify as a “high sensitivity” headphone.
Ironically, the big gain here may be the alterations in sonic signature occasioned by the search for more sensitivity. The sonic signature of the HE-500 is something special, and I think this model finally erases the hesitance of some of our reviewers to admit HiFiMAN to the top echelon of headphone manufacturers.
Consider this headphone if: you want a headphone that delivers pretty much the full wish list: ultra wide-range frequency response, accurate tonal balance, great bass, excellent resolution of low-level sonic details, and low distortion. Oh, and give the HE-500 an extra-careful look if you’re willing to use a headphone that needs a very good amplifier to show its stuff.