Design and features:Although this portable ear-insert model lacks active noise reduction, the earplug-like design helps to reduce both outside noise and sound leaking out into your environment. The earphones also have high sensitivity, so they can provide satisfying volume levels even when used with lower-powered portable audio devices. The Synchros S100a has an inline volume control that works with some Android models, plus an integrated microphone and player function controls that are compatible with Android devices, iPads, some iPods, and some iPhones, and some other cellphones. The call connect/disconnect button can be used with some Android and iPhones and some other cellphones. These earphones may not operate properly with some non-Android, non-iPod players or other audio equipment. This model comes with four pairs of earpieces of various sizes and types and a carrying case.
Sound quality: The Synchros S100a delivers good overall sound, with a warm character. Bass has good impact but is prominent and boomy, and midrange is even but a bit soft. Treble is extended, but recessed and slightly soft. Overall sound is somewhat closed in, with decent dynamics.
Comfort: We found that these earphones fit and stay in place with no problem, but they produce a sense of pressure in the ear opening that might be uncomfortable for some.
