Treble describes the high-range spectrum of frequency response, which spans from 2.5kHz up to 20kHz.
The high tones are the sharper sounds you can hear in music. Hi-hats, cymbals, sibilance, and the higher harmonics of other instruments all lie within this spectrum and add brightness to the audio.
For treble performance, we measure the low-treble, mid-treble, and high-treble frequency response, then we use these values to test the standard error of the treble reproduction.
Treble matters for vocals and higher harmonics of instruments such as cymbals and hi-hats, which add brilliance to music. Headphones with great treble performance reproduce the high-range spectrum of a track as it was arranged.
An over-hyped treble profile will make audio tracks sound too sharp for most ears, especially if bass and mids are lacking in comparison to the treble. Inversely, an under-hyped treble profile will cause some tracks to sound dull and heavy. Also, frequencies within the 15kHz up to 20kHz range are age dependent and are therefore not audible to everyone.
Treble sensitivity thresholds vary from user to user, some high frequencies causing more discomfort to certain listeners than others. Listening habits are also important as different treble profiles may be more noticeable with music than movies or audiobooks.
Standard Error for the Treble Range shows the amount of deviation of the measured Treble response from the target Treble response. It is calculated using a formula similar to the STDEV.P in Microsoft Excel.
However, a perceptual weighting filter is applied prior to the Std. Err. calculation since humans are less sensitive to sounds in the high-treble region. Our weighting filter starts at 12kHz and progressively reduces the weight of the error down to 20kHz, where it reaches 1/10th of the baseline weight.
Since high frequencies have very short wavelengths, they are highly sensitive to positioning preference and head/ear shape. Therefore, most headphones show inconsistencies in their Treble response across multiple re-seats on the same head, and also between different heads.
The low-treble value is calculated by averaging the amplitudes of each frequency within the low-treble region. The final value is then reported relative to our target amplitude of 90dB.
A low-treble value of +3dB means that the average low-treble amplitude of the headphone under test was 93dB. This value can be considered as a metric for the "amount" of low-treble produced by the headphones, rather than the "accuracy" of the reproduction, which is determined by Treble Std. Err.
Since the low-treble region is where instruments get their clarity, detail, and articulation, a headphone with a negative low-treble value would be perceived as lacking clarity and detail, especially on vocals and leads. Conversely, a headphone with a positive low-treble value could sound harsh and forward and even painful at times.
The treble value, similar to low-treble, is calculated by averaging the amplitudes of each frequency within the treble region. The final value is then reported relative to our target amplitude of 90dB.
A treble value of +3dB means that the average treble amplitude of the headphone under test was 93dB. This value can be considered as a metric for the "amount" of treble produced by the headphones, rather than the "accuracy" of the reproduction which is determined by Treble Std. Err.
The treble region is where presence, brightness, and sibilance (S and T sounds) come from. Therefore, a headphone with a negative treble value would tend to sound dark and lispy (lacking S and T). Conversely, a headphone with a positive treble value could sound overly bright, piercing, and even painful at times.
The high-treble value, just like low-treble and treble, is calculated by averaging the amplitudes of each frequency within the high-treble region. The final value is then reported relative to our target amplitude of 90dB.
A high-treble value of +3dB means that the average high-treble amplitude of the headphone under test was 93dB. This value can be considered as a metric for the "amount" of high-treble produced by the headphones, rather than the "accuracy" of the reproduction which is determined by Treble Std. Err.
High-treble, similar to low-bass, is mostly felt than heard. However, in high-treble, this is due to the very high frequencies that occupy the high-treble region, whereas in low-bass it is the opposite. Humans tend to lose sensitivity to very high frequencies with age, so some of the errors and deviations in this region may not be audible to some.
This is the region where airiness and brilliance come from. Therefore, a headphone with a negative high-treble value would be perceived as lifeless and closed-up. Conversely, a headphone with a positive high-treble value may be perceived as sounding hissy and excessively airy. It should be emphasized that measurement results in high-treble are highly sensitive to placement and head/ear shape.