ZMF Atticus Sealed Over-Ear Headphones Measurements

Click on graphs image to download .pdf for closer inspection.

Raw frequency response plots show the Atticus shows some significant changes in level and tonality with pad position and seal. I wouldn't surprise me to find that a better seal on a real person's head would yield a fuller bass response. Raw response shows a bass response with a large, broad mid-bass hump. It drops to the midrange level by 300Hz; I did not hear it as particularly intrusive on the midrange.

Response thereafter to the hump at 3kHz is on a roughly 5dB warm tilt with respect to a neutral target. Above 3kHz a large notch appears that over reduces sibilant and sparkly sounds. Response 10kHz and above is on target.

30Hz square wave is quite swayback echoing the bass hump inflection at 120Hz and possibly the phase shift due to the primary driver resonance at 60Hz, which can be seen in the impedance plot.

300Hz square wave should have more overshoot of the initial transient, and less subsequent undershoot. The general upward slope indicates a warm headphone in the mid to treble transition.

Impulse response shows the headphones were wired in reversed absolute polarity. This and the 300Hz square wave show a somewhat noisy headphone, and, in addition to the tonal imbalance, I did hear the treble as somewhat blurred.

Interestingly, the distortion plot is actually a bit better than the Eikon. Again, I heard no significant change in the character of the sound around the peak at 1.7kHz.

Impedance plot shows a nominally 330 Ohm headphone with a mild primary driver resonance at about 60Hz, and a mild resonance near the driver at 1.7kHz.

Isolation at -21dBspl broadband is good for a headphone of this type. Needing 238mVrms to achieve 90dBspl at the ear mean this headphone will sometimes not play to a solid listening level with portable devices.

ZMF Headphones