Design and features:This model has touch controls for music player play/pause, next/prev track, call connect/disconnect, and volume; the controls can also be set to operate noise cancellation/ambient sound monitoring or digital voice assistant activation. Either earphone can be used alone for one ear monitoring of Bluetooth streamed audio and telephone communications. It has an automatic pause feature - audio pauses when one earphone is taken out of ear and resumes when both are put back. It has an "Immersion" spatialization feature that works with any audio content, and it supports digital voice assistants when used with Bluetooth devices that have those capabilities. The charging/carrying case has a built-in rechargeable battery that the manufacturer claims can be used to recharge the earphone batteries up to 3 times (to add an additional 18 hrs. of playtime for a total of 24 hrs.) between its own charges. The free Bose Music app for Apple and Android mobile devices adds additional features.
Sound quality:We found the QuietComfort Ultra Earbuds provides excellent active noise reduction and 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. The overall sound can best be summarized as bassy and somewhat grainy. With the noise cancelling mode set to Quiet and the EQ set to flat (the default setting) in the Bose Music app, the bass (as in bass drums, bass guitars, stand-up bass, etc.) goes deep, but is prominent and thuddy, and the impact can be a touch excessive. The midrange (voices, guitars, horns, etc.) is a touch thin, somewhat grainy, a bit hazy and congested (think sonic traffic jam), and is somewhat overwhelmed by the bass. The treble (cymbals, the upper range of violins, etc.) is extended, but is a bit smeared. The sound also has a good sense of liveliness and is somewhat open--sound-wise it almost seems like you don't have anything plugging up your ears. It also does a decent job of recovering the room ambience of recordings. These earphones provide excellent noise reduction across the entire frequency range with the low frequencies reduced the most. A rushing noise is audible when there is no audio program material to mask it.
Comfort and Fit:This is a hybrid ear insert/ear bud design - the earpieces seal the ear canals but they don't insert into the ear canals as far as typical ear insert models, and they are supported by ear bowls like a ear bud model rather than the ear canals.
Small
Users with small ear bowls might find that the earphone body feels a bit bulky in their ear bowl and that they stick out too far and feel like they may lever out of place, but that they will generally stay in place during casual use and are very stable even with vigorous head movement.
Medium/Large
Users with medium and large size ear bowls will probably find that they stay in place during casual use with no problem, and that the ear bowl supports make the ear pieces very stable even with vigorous head movement.
Incidental contact with the touch controls can cause unintentional playing and pausing.
Hitting the stem that hangs out of the ear can knock an earphone loose and cause it to fall out of the ear.
