Design and features:The headphones work with or without the noise-canceling feature being turned on. You can use the noise-canceling feature without listening to music. These headphones can be used wirelessly with Bluetooth devices or can be cord connected. When cord connected they have high sensitivity when the noise cancelation feature is turned on so they can provide satisfying volume levels when used with lower-powered portable audio devices. When unpowered or powered but the noise cancelation feature is turned off they have medium-high sensitivity; so they can provide satisfying volume levels when used with home audio equipment and even lower-powered portable audio devices. The MDR-1000X has an integrated microphone and touch sensitive volume, music player function, and call connect/disconnect controls that work with paired Bluetooth devices. Additional features include automatic optimization of its noise cancelling characteristics based on the noise environment, a function claimed to optimize noise reduction if the ear pads don't seal around the ears because of the user's head shape, hair style, or eye glass use, momentarily audio program muting and engagement of the ambient sound monitor mode when the entire hand is placed on the right earcup, the ability to receive high resolution audio Bluetooth transmissions from selected Sony products, optional NFC Bluetooth pairing, and earcups swivel to flat for ease of carrying and storage. This model comes with a detachable 56-inch long standard audio cable, a USB charging cable, a mini-plug-to-airplane-jack adapter, and a carrying case.
Sound quality: We found the MDR-1000X provides excellent active noise reduction and that the sound quality was in the same range regardless of whether the noise cancelling feature was turned on or off, or whether it was used in the Bluetooth or powered wire connected mode. When used in any of those four modes it delivers sound quality that falls in the very good range - it reproduces music and voice very well although it does have some noticeable sonic quirks. When the noise cancelling feature is turned on there is no significant difference between the Bluetooth and the powered cord connected modes and the overall sound can best be summarized as a bit bassy and plasticy. Bass (as in bass drums, bass guitars, stand-up bass, etc.) has good impact and goes deep, but is slightly prominent and boomy. The midrange (voices, guitars, horns, etc.) is fairly even, but is a bit soft and has a noticeable plastic resonance (something like what you would hear if you talked into a semi-rigid plastic cup). The treble (cymbals, the upper range of violins, etc.) is extended but sizzly (sounds that should have a delicate shimmer have a sound reminiscent of bacon frying) and uneven - depending on the program material it can sound a bit prominent or subdued. While the sound has a good sense of liveliness it is somewhat closed-in -- sound-wise it is somewhat obvious that you have something covering your ears. When the noise cancelling feature is turned off the sound is similar, but the bass goes from slightly prominent to slightly subdued and the treble goes from slightly subdued to somewhat prominent; and again there is no significant difference between the Bluetooth and the powered cord connected modes. When cord connected and unpowered (the 5th mode) the overall sound can best be summarized bassy and somewhat muffled, and the overall score drops to the low good range. These headphones provide excellent noise reduction that is fairly even across the entire frequency range. A very faint hiss can be heard when there is no audio program to drown it out. The noise cancelling optimizer function did not seem to make much of a difference, so if it does have an effect it appeared to be very subtle.
Comfort: We found that these headphones produce a sense of moderate pressure on the ears. As typical of over-ear models the ear pads might feel hot and/or sticky after prolonged use. Incidental contact with the touch controls on the right outer earcup can cause unintentional pausing, track skipping, or volume level changes. When wearing this model while walking the vibrations from each foot step can be heard through the headphones when the power is off; the sound of your footsteps are reduced as you go from ambient mode to ambient voice mode, and can only faintly be heard in noise-cancelling mode. We also found that this model has a poor folding design - if care is not taken when unfolding the MDR-1000X the hinges can pinch a finger. While the pinch is not severe enough to break a bone it can be painful.
