- Audio frequency response over Bluetooth
- 4 Answers 4
- Sony WH-1000XM4
- Test report — general data Sony WH-1000XM4 headphone
- Frequency response of headphone
- Perception of headphone frequency response curves of equal loudness ISO 226-2009
- Frequency response of headphone Sony WH-1000XM4 Bluetooth headphone
- Perception of headphone frequency response curves of equal loudness ISO 226-2009
Audio frequency response over Bluetooth
Introduction : Using some binaural beat meditation, the vendor claims that their sound frequency goes down to 5 Hz to get better meditation quality. Even though the human ear can’t hear 5Hz, the brain responds to it. The vendor advised using wire headphones because the Bluetooth frequency response is from 20Hz. Question: Why can’t Bluetooth decode 5Hz frequency? I thought the audio is transmitted in binary raw data, and the headphone will decode wherever it receives.
4 Answers 4
Ignore their recommendations.
Binaural beats generate the beat in your mind. They use audible sounds that are close together in frequency (say, 1000 and 1005 Hz.) Your hearing generates the beat from the difference. Playing the 1000 and 1005 Hz will cause you to perceive a 5Hz «beat» that exists nowhere physically — it is literally all in your head.
It doesn’t matter if the speaker, headphone, or audio system can convey a very low frequency signal because the low frequency isn’t actually there. Only the normal audio frequencies need to be conveyed. Bluetooth should do just fine. Hifi systems may go down to 20Hz while others may cutout the low frequencies below 100Hz.
Bluetooth and other audio systems usually filter out low frequencies. Your ear can’t hear them and the speakers can’t effectively reproduce them, so they are filtered out. It saves bandwidth and power when you don’t transfer sounds that no one can hear anyway.
Binaural beats are a thing.
Whether they have any influence on your meditation or whatever is an entirely different question that can’t be answered here.
Sony WH-1000XM4
Test report — general data Sony WH-1000XM4 headphone 
Frequency response of headphone
Perception of headphone frequency response curves of equal loudness ISO 226-2009
| Variation in frequency response in band from 100 Hz — 10 kHz | 0.0, +0.0 | dB |
| Measurements were performed on the stand: | HDM-X  | |
Translation of the description is not yet ready
Clicking on the graph will take you to the comparison page of different models with advanced graph display settings.
Frequency response of headphone Sony WH-1000XM4 Bluetooth headphone
| Channel: | Left | Right | |
| Variation in frequency response in band from 100 Hz — 10 kHz | -9.3, +6.8 | -7.0, +8.3 | dB |
Graph of frequency response the shows the balance of the frequency of the headphones (reproduced frequency spectrum) in dB. 0 dB is the average of the amplitude.
The frequency response of the headphones can be represented as the selected equalizer setting in the player, applicable to headphones with a flat sound. Subjective «flatness» is perceived differently from external conditions: the volume level of the external noise and noise isolation headphones. When connected to an amplifier, the frequency response can change .
The difference in amplitudes of 6 dB is equivalent to a twofold ratio of signal levels.
Original text in Russian report. You can help with translation via the feedback or select text and press Ctrl+Enter (anonymously).
Clicking on the graph will take you to the comparison page of different models with advanced graph display settings.
Perception of headphone frequency response curves of equal loudness ISO 226-2009
Variation in frequency response in band from 30 Hz — 12 kHz
| Channel: | Left | Right | |
| Deviation -36.0 dB | -9.0, +11.2 (20.2) | -10.0, +13.3 (23.3) | dB |
| Deviation -24.0 dB | -8.7, +9.2 (17.9) | -9.7, +11.3 (21.1) | dB |
| Deviation -12.0 dB | -8.7, +7.2 (15.9) | -9.5, +9.4 (18.8) | dB |
| Deviation 0.0 dB | -10.6, +6.9 (17.5) | -9.2, +7.4 (16.6) | dB |
| Deviation 12.0 dB | -12.5, +11.1 (23.6) | -9.7, +10.1 (19.8) | dB |
| Deviation 24.0 dB | -14.4, +15.2 (29.6) | -11.6, +14.2 (25.8) | dB |
| Deviation 36.0 dB | -16.1, +19.3 (35.5) | -13.4, +18.3 (31.7) | dB |
Variation in frequency response in band from 40 Hz — 1 kHz
| Channel: | Left | Right | |
| Deviation -36.0 dB | -9.0, +11.2 (20.2) | -10.0, +13.3 (23.3) | dB |
| Deviation -24.0 dB | -8.7, +9.2 (17.9) | -9.7, +11.3 (21.1) | dB |
| Deviation -12.0 dB | -8.7, +7.2 (15.9) | -9.5, +9.4 (18.8) | dB |
| Deviation 0.0 dB | -10.6, +6.9 (17.5) | -9.2, +7.4 (16.6) | dB |
| Deviation 12.0 dB | -12.5, +11.1 (23.6) | -9.7, +10.1 (19.8) | dB |
| Deviation 24.0 dB | -14.4, +15.2 (29.6) | -11.6, +14.2 (25.8) | dB |
| Deviation 36.0 dB | -16.1, +19.3 (35.5) | -13.4, +18.3 (31.7) | dB |
The graph shows the change in the perception of the frequency response of the headphones when listening to music with a different loudness relative to the natural level. When listening to headphones at a low volume, the perception of recoil in the low frequency range decreases, and when you listen to it at a high volume, it increases.
According to this graph, you can estimate at what volume the headphones will be perceived more flat.
The perception of the number of low frequencies depends on the volume according to the curves of equal loudness. (ISO 226-2009 Acoustics. Normal equal-loudness-level contours). For the base level, 72 dB SPL (live performance of several instruments with vocals without amplifiers with acoustics) is selected.When you select another base level, the dependence varies slightly and is suitable for almost all levels.
Original text in Russian report. You can help with translation via the feedback or select text and press Ctrl+Enter (anonymously).
Clicking on the graph will take you to the comparison page of different models with advanced graph display settings.