Gear & technology
Wireless
Also called wireless headphones, true wireless, TWS
Wireless headphones and speakers receive audio over Bluetooth or Wi-Fi instead of a cable, with a battery, DAC and amplifier built in. They trade some fidelity and the ability to upgrade parts for convenience and features such as noise cancelling.
Over Bluetooth the audio is compressed by a codec such as SBC, AAC, aptX or LDAC, so a wireless headphone rarely receives a Lossless signal; aptX Lossless can deliver one on the few phone and headphone pairs that support it. Wi-Fi speakers and streamers can carry lossless audio, and most run on mains power.
Because the DAC and Amplifier are inside and tuned by the maker, the sound of a wireless headphone is fixed, and digital processing often shapes it heavily. That is not a flaw in itself: many popular headphones are wireless, and many owners value noise cancelling over the last degree of fidelity. The catalog flags products as wireless where the maker says so.