Design and features:This noise-canceling home/studio-style over-ear model has a closed design and electronic noise canceling feature reduce both outside noise and sound leaking out into your environment. The headphones work with or without the noise canceling feature being turned on. You can use the noise-canceling feature without listening to music, and the audio cable can be detached to get it out of the way when the headphones are being used for noise reduction only. The headphones have very high sensitivity in the active mode and when the noise cancelation feature is turned on--they have medium-high sensitivity in the passive mode--so they can provide satisfying volume levels when used with home audio equipment and even lower-power portable audio devices. The M4U 2 has an in-line integrated microphone, player function controls, and call connect/disconnect controls that are compatible with iPads, some iPods, and some iPhones and some other cellphones. Additional features include an amplified non-noise-canceling operation mode, dual-input connections, and earphones that fold for ease of storage. This model comes with extra earpads, a detachable audio cable with built-in remote and mic for iPod/iPhone connections, an alternative detachable audio cable for non-iPod/iPhone connections, a 1/4-inch plug adaptor, mini-plug-to-airplane-jack adapter, and a carrying case.
Sound quality: The M4U 2 delivers very good overall sound quality, with a very warm character and excellent active noise reduction. Bass has good impact but so-so definition, and lacks crispness. Midrange is smooth but a little dark and soft. Treble is detailed, but upper treble is slightly rolled off. Overall sound is a bit closed in, with decent dynamics. In the active mode with the noise reduction feature turned off, the sound quality is similar to when the noise reduction feature is turned on, except the bass is a bit recessed and the midrange is more neutral sounding. In the passive mode with the noise reduction turned off, the sound quality is similar except the bass is slightly more recessed and lacks a bit of impact, and midrange is smooth but a little soft. These headphones provide excellent noise reduction , but produce a very slight hiss and mid-pitched whine which is evident in quieter passages in music and when ambient noise doesn't mask it.
Comfort: We found that these headphones are generally comfortable, though there is a sense of moderate pressure around the ears. The vinyl earpads might feel hot and/or sticky after prolonged use. The loudness difference between active and non-active modes is huge, and can be very jarring if you switch between these modes while wearing headphones and listening to a program. When using the active operation, we had compatibility issues with some home audio equipment that produced various levels of hiss and other noises in the headphones.
