Sennheiser CX 400 In-Ear Headphone (Black)


Pros: light, extension cable, competent
Cons: veiled

The CX 400 is high quality, noise-isolating ear-canal earphone with a powerful, bass-driven stereo sound for listening on the go. It's feature a short cable, perfect for use with mobile phones or MP3 players with a remote-control and/or microphone. With the included 1 m extension cable the CX 400 can also be used with a player carried in your pocket.

General Information
Manufacturer Website Address
Brand NameSennheiser
Product SeriesCX
Product TypeEarphone
ManufacturerSennheiser Electronic Corporation
Manufacturer Part Number500937
Product NameCX 400 Stereo Earphone
Product ModelCX 400
Technical Information
Sound ModeStereo
Minimum Frequency Response17 Hz
Connector PlatingGold Plated
Connectivity TechnologyWired
Impedance16 Ohm
Cable Length30 cm
Maximum Frequency Response21 kHz
Package Contents
  • CX 400 Stereo Earphone
  • 1 x Set of CX ear fit adapters (S/M/L)
  • 1 x Cable Clip
  • 1 x Carrying Pouch
  • 1 x Cable Winder
  • 1 x Extension Cable (1 m)
Earpiece DesignEarbud
Earpiece TypeBinaural
Physical Characteristics
Form FactorOpen
Host InterfaceMini-phone
Limited Warranty2 Year


Solid, small, light, comfortable IEM. Ergonomics are really fantastic. Fit is great so reproduction easily goes to sub bass frequencies. Bass is elevated but not overwhelming. Veiled sound, lacking details.
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New Head-Fier
Pros: Ok for the price.
Cons: fit was average, sound was average, quality was average.
I was hoping for a bit more but I guess I should have spent more. They were used for a few months of jogging before I started looking for a replacement.


1000+ Head-Fier
Pros: Comfort,
Cons: Overly boomy bass,
I bought my pair of cx400 to replace my cx300 and was expecting it to be a more refined version. I was, it's pretty safe to say, disappointed. The sound you get from these is far too similar to the 300's for their own good. I had the same problems with the cx400 as the 300. So I got boomy bass which drowns out the rest of the range.In this day and age I can't think of one good reason why you should buy the cx400's, there are earphones out there which are just as cheap and do everything better. They're certainly not worth the full retail price.
The shallow fit and comfort could be a good selling point but because of this and the cable design micro-phonics and isolation are not very good either. As with most sennheiser's there are many fakes of varying quality out there.