Measuring headphone performance accurately and relevantly requires the use of expensive test equipment. but simple subjective evaluations using special test signals can give a quick idea of the headphone’s performance. here are some that you may find useful.
exponential sine sweep
A slow exponential sine sweep (sometimes called a logarithmic or logarithmic sine sweep) is one way to assess the tonal balance of a headphone. The MP4 video below includes a 1Khz starting tone to help you set a suitable and comfortable playback level; start with the volume low, before going from 10hz to 10khz over a period of 40 seconds, which equates to a sweep rate of one octave in four. seconds. over the course of the sweep, the cursor displays the instantaneous rate, so if you hear an anomaly, you can pause the video and see what rate it occurs at.
Reading: Headphone distortion test
You should not expect to hear a constant output level as a function of frequency with this signal. if you use a typical playback volume, then a headphone with a flat frequency response below 1 kHz will provide a gradually increasing perceived output up to that frequency due to the volume characteristics of the ear.
Beyond this, between 1kHz and 10kHz, the output level should appear constant and the sweep tone should remain in a center position rather than moving from side to side. with many modern headphones, which have a light treble tonal balance, the output level will seem to drop a bit above 1khz, but it shouldn’t fluctuate much. spikes in the treble output at around 8 kHz will generally result in sibilant emphasis, while large changes in image position indicate significantly different frequency responses in the two ears. if you hear similar changes regardless of which headphones you use, you may have different hearing acuity in your left and right ears and this is responsible rather than the headphones. try wearing the headphones backwards and see if the same effects persist.
If you listen to the output before the sweep reaches 20hz, you may experience harmonic distortion products if your headphones have poor low-frequency linearity.
For private, non-commercial use, you can download the mp4 video via the right mouse button menu.
As all headphone users know, headphones have quite a different “image” than speakers when playing conventional stereo recordings. the speaker soundstage, which covers an arc from 30 degrees left to 30 degrees right with a conventional equilateral triangle layout of speakers and listening position, with headphones becomes a line of image positions that are extends from the left ear to the right ear. ideally, what are equally spaced positions on the loudspeaker soundstage should translate to equally spaced image positions on the headphone listener’s head. or, if externalization of the headphone image is achieved (usually by electronic processing), it should behave similarly to the speaker image.
This test track helps determine if this is the case. it is constructed from a mono violin recording made in an anechoic chamber. was created for auralization purposes (the simulation of acoustic spaces), while here it is used to flip the speaker image from 30 degrees left to 30 degrees right in 5-degree increments, which is equivalent to the headphones from left to right by 13 degrees. Steps. it starts with the violin playing in the center, to allow level adjustment, then moves progressively from left to right, the green circle showing which position of the picture is currently playing.
Ideally, the 13 image positions should be evenly spaced, the image should always be narrow with no signs of stretching, the central image should be exactly central, and the tonal balance should remain constant. what you will sometimes hear, because the violin recording has a wide bandwidth and strong partials (harmonics), is that the hard left or hard right signals excite diaphragm resonances that are less apparent elsewhere , and/or that the tonal balance differs at each end of the range due to differences in frequency response in the left and right ears. if the center image is shifted, there may be a disparity in the sensitivity of the left and right headphone capsules. As seen with the exponential sine sweep test, if you hear this effect regardless of which headphones you use, you may have different hearing acuity in your left and right ears and this is responsible rather than the headphones. try wearing the headphones backwards and see if the same effects persist.
For private, non-commercial use, you can download the mp4 video file via the right mouse button menu.
lateralization test audio
Headband resonance test
Many headphones suffer from headband resonance, but it is rarely discussed in reviews and measured less frequently. but it’s surprisingly easy to subjectively test the vibration and resonance of the headband, using the audio file below.
comprises 26 successive one-second bursts of periodic pink spectrum noise, having a line spectrum from 20hz to 20khz at 1hz intervals, in the left channel only. because the signal is confined to the left channel, ideally it should be heard as coming from the left headphone capsule only. whereas, generally, what you hear is a sound transmitted towards the right side of the head, sometimes accompanied by an obvious coloration that results from the structural resonance of the headphones. you may find that you can hear this more clearly if, while the signal is playing, you remove the headphones from your right ear and then put them back on.
Tip: If you can figure it out, I’ve found that headband resonances are often more easily heard if the headphones are powered from a high-resistance source. try 100 ohms or so.
For private, non-commercial use, you can download the audio file via the right mouse button menu.
Headband resonance testperiodicpinknoise30s