Reviewed on: SoundStage! Solo, August 2020

I measured the EarFun Air earphones 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. An Mpow BH259A Bluetooth transmitter was used to send signals from the Clio 10 FW to the earphones. These are “flat” measurements; no diffuse-field or free-field compensation curve was employed. Note that because of the latency introduced by Bluetooth, I wasn’t able to do a spectral-decay measurement, and of course my usual impedance and sensitivity measurements are irrelevant for wireless earphones. If you’d like to learn more about what our measurements mean, click here.

Frequency response

The above chart shows the Air earphones’ frequency response measured with the RA0402 ear simulator. As with the EarFun Frees, this is pretty much a “by the book” response for good-sounding earphones.

The impulse response shows that the latency with the Mpow BH259A is 246ms. This is typical for true wireless earphones, and it means you will probably notice lip-sync errors when you watch videos using the Airs. In most cases, it’ll be best to stick with music and podcasts when using these.

Frequency response

This chart shows the Airs’ right-channel response compared with other true wireless earphones (EarFun Frees and Sennheiser Momentum True Wirelesses), as well as with the AKG N5005s, the earphones said to best reflect the Harman curve. As with the Frees, the Airs are at least in the ballpark of the Harman curve. The Frees’ weaker peak in the lower treble region is what makes them sound bassier.


Because of the latency of the Bluetooth connection, I could not use Clio’s sine sweep function to measure total harmonic distortion (THD) versus frequency, so I did discrete THD measurements of sine tones in one-octave steps. Distortion is very low at all frequencies and levels; there’s a little more in the upper mids and lower treble, but it’s well below 2%, so unlikely to be audible. Note that these earphones will play louder than the EarFun Frees, which weren’t able to reach 100dBA with pink noise.


This chart shows the Airs’ isolation versus other true wireless models: the EarFun Frees, 1More E1026BT-1 Stylishes, and Technics EAH-AW70s (which incorporate active noise canceling). The Airs’ isolation is very good for true wireless earphones without active noise canceling, comparable to that of the Frees.

. . . Brent Butterworth