I measured the HE1000 V2s using a G.R.A.S. Model 43AG ear/cheek simulator, a Clio 10 FW audio analyzer, a laptop computer running TrueRTA software with an M-Audio MobilePre USB audio interface, a Musical Fidelity V-Can headphone amplifier, and an Audio-gd NFB-1AMP amplifier for distortion measurements. This is a “flat” measurement; no diffuse-field or free-field compensation curve was employed.
The HE1000 V2s’ frequency response is about par for the course for headphones of this type, with flat response below 1kHz and strong treble response between 2 and 10kHz.
Adding 70 ohms output impedance to the V-Can’s 5 ohms, to simulate the effects of using a typical low-quality headphone amp, doesn’t affect the HE1000 V2s’ tonal balance. Still, a low-quality headphone amp may not deliver satisfying volume from the HE1000 V2s.
This chart shows the HE1000 V2s’ measured treble response compared with the original HE1000s and the Audeze LCD-Xes, another set of well-regarded, high-end, open-back headphones. The HE1000 V2s are similar to the original model, but with more treble response between 5 and 8kHz.
This spectral-decay (waterfall) chart indicates that the HE1000 V2s have the “Portuguese man-of-war” plot produced by many large planar-magnetic headphones, with many extremely high-Q (narrowband) resonances, as well as a fairly high-magnitude resonance centered at 5kHz.
The total harmonic distortion (THD) of the HE1000 V2s, measured with pink noise, is practically nonexistent: just 1% at 20Hz, even at the extremely high test level of 100dBA.
In this chart, the external noise level is 75dB SPL; the numbers below that indicate the degree of attenuation of outside sounds. For comparison, I’ve included the isolation plots of the original HE1000s, the Audeze LCD-Xes, and the NAD Viso HP50s, which are midpriced, closed-back headphones. As usual, the open-back models offer almost no isolation from outside sounds.
The HE1000 V2s’ impedance is almost dead flat at 35 ohms; their impedance phase response is also flat.
The sensitivity of the HE1000 V2s, measured between 300Hz and 3kHz with a 1mW signal calculated for the specified 35 ohms impedance, is 86.9dB. That’s very low; consider a decent headphone amp with at least 6dB more output than an iPhone essential to get the best performance from these headphones.
. . . Brent Butterworth