Summary: I bought these thinking they'd be a better alternative to the IPOD headphones. Truth is, now I have more respect for the little white earbuds that shipped with my IPOD nano video.
These sennheisers don't live up to the name, and appear weak in every aspect of sound compared to the standard issue ipods.
Also, the buds on the sennheisers are slightly larger than those on the ipods .. so they don't fit in my ear as well.
Summary: but that's it, just OK. I wouldn't say they're any better than the iPod earphones. The bass is just average, the overall clarity is average. They're good for the price, however. And Sennheiser is a great company with solid products. I also own Etymotic er4 isolators, and they're far superior, but they cost well over $150.00. I guess for the price the MX51's do the job.
Summary: Very good entry level earphones and for the price probably the best. And for all the people who don't like IECs this is a very good option. Far far better than what iPod or creative mp3 players comes with by default. You must buy atleast these if not better ones if you at all care for quality in listening to music on portable players.
Excerpt: THE SENNHEISER EAR PHONE ARE BRILLIANT IN EVERY THING I HAVE TRIED THEM IN ,EVEN AN OLD STEREO RADIO WHICH USED TO HAVE AN ANNOYING BACKGROUND HISS BUT NOT ANY MORE THE HISS HAS COMPLETELY GONE I HAVE PUT THIS INFO IN THE REVIEW BECAUSE ITS A SIGN OF GOOD QUALITY EAR PHONES. I HAVE EVEN USED THEM WITH MY MOBILES MP3 PLAYER WITH FANTASTIC RESULTS ,AS WE ALL KNOW MOBILE PHONES ALWAYS SEEM TO COME WITH CHEAP TINNIE ONES FOR SOME REASON.
Excerpt: These headphones are ok, they produce very nice sound, good treble tones, but they lack BASS!!!!!!!!!! Which is the reason i bought them for £15 from HMV because it said POWERFUL BASSWIND system!! The headphones sound rubish at high volumes. They are reasonably comfortable, but sometimes keep dropping out my ears which is annoying.
Excerpt: Sennheiser MX51 Ear Phones are a reasonably priced, reasonably designed earphones that slot in just under the average price for sennheiser earphones and so sit in the middle of Sennheiser's vast range. Basic Stats Frequency Response: 19 -21,000 Hz Impedance: 64 ohms Sound Pressure Level: 116dB. Cable: Symmetrical Cable Length: 1.2m Design These earphones are black with some chrome-effect edge to detail on the ear piece.
Pros: Slim and subtle design . Quality of sound . Sennheiser reliability .
Cons: Slim design could be a potential structural weakness .
Summary: Der Klang ist ok, aber er ist leiser als der Originalkopfhörer der zu meinem MP3 Player mitgeliefert wurde. Ergonomisch guter Sitz, aber nichts für Leute mit kleinen Ohren. Für Gelegenheitshörer empfehlenswert, für Junkies nix. Dann lieber nen Euro mehr ausgeben.