Sennheiser MM 500-X Review

We can’t imagine that another set of headphones offers this much sound quality and convenience for anywhere near this price, making these the best all-around, reasonably priced set of headphones we have heard yet.
We can’t imagine that another set of headphones offers this much sound quality and convenience for anywhere near this price, making these the best all-around, reasonably priced set of headphones we have heard yet.
We can’t imagine that another set of headphones offers this much sound quality and convenience for anywhere near this price, making these the best all-around, reasonably priced set of headphones we have heard yet.

Highs

  • Supremely well-detailed and highly engaging sound
  • Wonderfully articulate bass; even better treble
  • Excellent fit, comfort and all-around build quality
  • Killer value
  • Fine assortment of accessories

Lows

  • Noise isolation only average
  • Price is starting to creep up

DT Editors' Rating

Home > Product Reviews > Headphone Reviews > Sennheiser MM 500-X Review

With a long and storied history as a high-quality transducer company, Sennheiser has developed a reputation for making some of the best traditionally designed headphones around. Some might say “conservatively designed,” but that ethos has continuously turned out one great-sounding set of cans after the next. Apparently, someone at Sennheiser saw fit to stir things up a bit: The company has started a line of less traditional, Bluetooth wireless-capable headphones to go along with the wired ones. The model we received for review, the MM 500-X, slots in at second-from-the-top of the Bluetooth line. Read on for our findings.

Out of the box

Pulling out the headphones from their high-quality window-box packaging was a snap – as long as we paid attention to which end we were trying to open. At the bottom of the box, we noticed a little graphic telling us to first snip the clear plastic retainer strip with pair of scissors. Then open the bottom flap and pull out the contents. We’re not sure why a plastic strip “seals” the box instead of tape, but we imagine Sennheiser has its reasons. As long as we didn’t try to open the package from the top and consequently ruin that beautiful packaging, getting to the goods was easy-peasy.

Other than the absence of a wire and an inconspicuously integrated button pad on the right ear-cup, the MM 500-X looks and feels like any other premium-quality set of Sennheiser cans. We appreciated the simple, not quite “murdered-out” smooth black finish of the headphones. We also liked the precision with which all of the various bits ‘n bobs fit together. The leatherette-wrapped ear cushions and headband feel especially nice to the touch, and everything else about the MM 500-X exudes quality.

Once we pulled out the inner contents, we found a well-thought-out assortment of accessories, including a USB-compatible wall charger and cable, US, UK, EU and AU power adapters, headphone-to-mini-jack audio cable, in-flight and quarter-inch adapters, a carrying case, a quick-start guide, and a full CD-ROM user manual.

Features and design

The Sennheiser MM 500-X features a circumaural (around the ear), closed-back design, making the headphones suitable for commuting or travel via public transport. The leatherette headband we mentioned earlier features plenty of padding on its underside; the same leather-like material wraps the ear-cup cushions. The ear-cups are attached via internal metal bands that slide in and out of the headband for a wide range of adjustment. The ear-cups also include tilt/rotate adjustment for compact storage and better fit for various noggin sizes.

sennheiser mm 500 x review black headphones bottom bluetooth over the ear headphones

The MM 500-X utilizes Bluetooth technology for its wireless audio transmission. A built-in microphone is available for talk functions when used with compatible Bluetooth devices. The MM 500-X is also Apt-X compatible, meaning it can deliver high-resolution audio quality over Bluetooth transmission that’s said to be indistinguishable from wired when streaming from other Apt-X-capable devices.

As mentioned previously, a multi-function, soft-touch button pad is integrated into the right-side ear cup, and offers control over basic listening and talk functions. A dedicated Bluetooth button is located on the lower edge of the ear-cup and switches Bluetooth functions on and off. The button’s placement next to a headphone cable jack provides more traditional wired listening if desired. The MM 500-X also features a replaceable, rechargeable battery that lasts for up to 10 hours of listening and 20 hours of talk time; full battery charge takes approximately three hours.

If many quality features seem to be built into the MM 500-X, it’s because there are: All of the little design touches – including the cleverly concealed USB cable port, easily removable battery, supplied accessories and user-replaceable parts – point to a well thought-out and smartly designed set of headphones.

Performance

We used a variety of components to test the MM 500-X’s capabilities including a Dell Latitude D810 laptop; an Apple iPhone 4; a Schiit Lyr headphone amplifier; a Marantz NR-1602 A/V receiver; and a Denon DCD-CX3 SACD, Samsung BD-C5500 and Oppo BDP-83 Blu-ray player. We also had on hand a pair of Bowers and Wilkins P5 headphones for comparison.

Although the MM 500-X sounded great right out of the box, we decided to let the headphones break in for about 20 hours before putting them through their paces. Once we started listening, we were treated to some of the most detailed, highly engaging and naturally revealing sound we’ve ever heard from headphones, regardless of price. We were pretty much gob-smacked by the gads of detail we heard. Listen to anything that’s densely layered and well-recorded such as Strawberry Fields Forever from the Beatles’ Magical Mystery Tour album. You’ll hear how every instrument’s complete sonic envelope – including the attack, sustain and decay components – are reproduced cleanly and clearly through the MM 500-X.

sennheiser mm 500 x revew black headphones folded over the ear headphones

To give you a better idea of just how much detail we’re talking about, try listening to Freddie Freeloader from that seminal Miles Davis album, Kind of Blue. Through the Sennheisers, we could easily hear every note of Paul Chambers’ wonderful but woefully under-recorded bass solo, a major accomplishment for any set of cans. Most other headphones would have us “squinting” our ears, straining to hear that upright bass through the mix. Not so with the Sennheisers: They cleanly, clearly, and effortlessly delivered all of the timbrel nuances and textural density of Chambers’ rich ‘n‘ fulsome bass.

Speaking of bass, the MM 500-X also delivered some of the most articulate bass we’ve heard from dynamic driver headphones. And there was plenty of it, too. Not too much, mind you, but definitely not anemic. Regardless of the type of music, everything we tried through the Sennheisers had a newfound level of pitch definition, articulation and clarity while delivering thumping goodness when called for. Listening to the synth bass from the title track of Massive Attack’s Protection album, we could feel those deep bass notes pulsating in our ears, all the while presenting the music with much more tone and tautness than we’ve ever heard through lesser cans.

If the Sennheiser’s bass was excellent – and it certainly was – its treble was even better. The MM 500-X had a brilliant, pristine clarity in the upper registers with some of the best top-octave extension we’ve heard yet. Turning back to that same Freddie Freeloader track, we could hear all of the natural shimmer and fine, bell-like ringing from Jimmy Cobb’s cymbals. These Sennheisers have a distortion-free purity in their treble that reminded us of a really good pair of electrostatic headphones – only without the super-high price tag.

Try as we might, we never had trouble with the Sennheiser’s wireless transmission quality. Sure, if we moved them beyond the max, 10 meters, line-of-sight distance to the transmitter, we could cause them to drop a signal. But never once did we experience any unintended dropouts, burps, hiccups or other strange noises. And they picked up the signal every time as long as our iPhone’s Bluetooth was active and connected.

sennheiser mm 500 x review black headphones earcups over the ear headphones

Seeing that these cans can also be used wired, we went back and forth between Bluetooth and wired, playing the same files from the same source (an iPhone 4) over and over. Even without an Apt-X compatible device on hand, we were hard-pressed to hear any meaningful differences. The Sennheiser MM 500-X sounded excellent both ways, and most of our audio performance observations are based on using them as Bluetooth headphones. Moreover, the fact that the MM 500-X sounded totally awesome when we used them with the lackluster audio output from an iPhone 4 speaks volumes about their versatility and overall sound quality, wireless or not.

Once we tried the Sennheisers with our Schiit Lyr headphone amp, however, the results were a different story: The MM 500-X sounded even better. Perhaps this should come as no surprise, seeing how the Lyr wipes the floor with the op-amp built into the iPhone. But if you really want to hear what these cans are capable of, run them with a good headphone amp. The MM 500-X were perfectly capable of keeping pace with the Lyr. They now had even better detail, more treble refinement and overall clarity. The hybrid amp brought out the best of the Sennheisers, allowing us to hear deeper into our favorite music.

In terms of fit and comfort, these Sennheisers are some of the best-fitting, most comfortable headphones we’ve tried. We could (and did) listen for hours on end, draining the battery down until we could listen no longer. Never once did we experience any listener fatigue – both physically and sonically. The MM 500-X never got hot or clammy either, providing a good, well-cushioned seal without putting our head in a vise grip. Furthermore, the headphones always remained secure, regardless of how crazily we decided to shake or move our heads.

sennheiser mm 500 x review black headphones headband over the ear headphones

The Sennheisers are about average regarding noise isolation. They did attenuate some noise, allowing us to better focus on the music. But we could still hear most normal-level conversations and TV sounds come through. Still, if these are anything like Sennheiser’s other headphones, my guess is the company knows full well how much noise isolation these headphones offer and decided to focus on sound quality instead. For those seeking a higher level of noise reduction, Sennheiser also makes the MM 550-X, which features active noise cancellation.

Conclusion

We’re completely smitten with the Sennheiser MM 500-X. Although their $330 retail price could put them beyond reach for some, their value is unquestionably off the charts. Their unrivaled combination of superior sound, excellent comfort and overall fit and finish puts them firmly at the top of their price class and makes them highly competitive with headphones costing much, much more. The fact that they’re also Bluetooth capable is icing on an already extra-special tasty and well-layered cake. Perhaps the best way to think of these headphones is not as a Bluetooth headphone first, but as a supremely musical and killer-sounding set of headphones that just happen to have Bluetooth built in.

Bottom line: We can’t imagine that another set of headphones offers this much sound quality and convenience for anywhere near this price, making these the best all-around, reasonably priced set of headphones we have heard yet. ‘Way, ‘way recommended for all music lovers.

Highs

  • Supremely well-detailed and highly engaging sound
  • Wonderfully articulate bass; even better treble
  • Excellent fit, comfort and all-around build quality
  • Killer value
  • Fine assortment of accessories

Lows

  • Noise isolation only average
  • Price is starting to creep up