The Sennheiser CX 400BT ranks #629 out of 668 total In-Ear Headphones for sound quality. See all Headphones rankings for every top pick.
Brand: Sennheiser
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#629 Sennheiser CX 400BT TWS Discontinued eBay
Pros: Bass is lifted about 3.9 dB with extension to 20 Hz, giving kick drums and bass lines extra weight. Lower mids sit within about 0.7 dB of target, keeping voices and guitars natural. It uses 1 x 7mm dynamic.
Cons: Discontinued, so it is mainly found used. Presence sits about 5.5 dB low with a 6.9 dB dip near 3.0 kHz, so vocals and instruments lose some bite. A Harman score of 49 places it in the lower part of the in-ear rankings.
| Released | 2020 (6 years ago) |
|---|---|
| Connection | True wireless |
| Deviation From Target | 3.52 dB standard deviation |
| Driver Type | Dynamic |
| Drivers | 1 x 7mm dynamic |
| Form Factor | In-ear |
| Frequency Response | 5Hz - 21kHz |
| Harman Preference Score | 49 (measured by oratory1990, via AutoEQ) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+1.2 dB at 30 Hz) |
| Tonal Tilt | -1.46 (negative is warmer, positive brighter) |
| Weight | 0 lbs (6 g) per earbud |
EQ preset to match the Harman target
Set a preamp of -4.7 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by AutoEQ from its measured frequency response.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | -3.1 dB | 0.70 |
| Peak | 179 Hz | -5.6 dB | 0.79 |
| Peak | 2,889 Hz | +4.8 dB | 0.72 |
| Peak | 67 Hz | +0.8 dB | 0.85 |
| Peak | 9,726 Hz | +1.3 dB | 1.91 |
| High shelf | 10,000 Hz | -0.2 dB | 0.70 |
| Peak | 794 Hz | +1.4 dB | 1.66 |
| Peak | 1,503 Hz | -0.8 dB | 2.02 |
| Peak | 307 Hz | -0.8 dB | 1.68 |
| Peak | 211 Hz | +0.6 dB | 2.88 |
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