Reviewed on: SoundStage! Solo, October 2020
I measured the Beyerdynamic T5 headphones using laboratory-grade equipment: a G.R.A.S. Model 43AG ear/cheek simulator/RA0402 ear simulator with KB5000/KB5001 simulated pinnae, and a Clio 10 FW audio analyzer. For isolation measurements, I used a laptop computer running TrueRTA software with an M-Audio MobilePre USB audio interface. The headphones were amplified using a Musical Fidelity V-CAN and Schiit Magnius. These are “flat” measurements; no diffuse-field or free-field compensation curve was employed. If you’d like to learn more about what our measurements mean, click here.
The first chart shows the frequency response. This is a little unusual in that there is the sharp rise in the bass characteristic of Harman curve headphones -- although at a somewhat higher frequency of about 300Hz, rather than 200Hz. Yet there isn’t the roughly 10dB rise in treble around 3kHz that Harman curve headphones would have.
This chart shows how the T5s’ tonal balance changes when they’re used with a high-impedance (75 ohms) source, such as a cheap laptop or some cheap professional headphone amps, or some exotic tube amps. There’s about a 1dB boost in the treble with the high-impedance source.
This chart shows the T5s’ right-channel response compared with several planar-magnetic headphones -- including the Dan Clark Audio Æon 2 Closeds, which are the planar headphones I’ve found to measure closest to the Harman curve, when they are used with the optional perforated earpads. The T5s’ response shows more of a bass boost than any of the other headphones shown here, but with less energy between 2 and 8kHz than the Æon 2 Closeds and the Audeze LCD-2 Closed Backs. This suggests the T5s would sound dull . . . but they don’t, at least not to me.
The T5s’ spectral decay plot shows a little more resonance in the bass than you’d probably see with a planar-magnetic model, but not enough to be sonically troublesome.
Harmonic distortion in the T5s is relatively high below 100Hz, although above 30Hz, it mostly stays below 2% at 90dBA (which is a very loud listening level) and 5% at 100dBA (a crazily loud listening level). For reference, the generally accepted threshold for audibility of distortion at these frequencies is about 10%, because the harmonics are all at low frequencies where the ear isn’t very sensitive.
In this chart, the external noise level is 85dB SPL, and numbers below that indicate the degree of attenuation of outside sounds. The lower the lines, the better the isolation. The isolation of the T5s is comparable to that of other large, closed-back audiophile headphones.
The T5s’ impedance magnitude is fairly flat, averaging about 40 ohms and swinging between 34 and 44 ohms. Impedance phase angle is also quite flat.
Sensitivity of the T5s, measured between 300Hz and 3kHz, using a 1mW signal calculated for 32 ohms rated impedance, is 102.0dB, so pretty much any source device can easily drive them.
. . . Brent Butterworth