Наушники — Koss UR23i

The Koss UR23i is a wired full-size headphone with closed cups, an over-ear fit and a microphone and remote built into its cable, aimed by Koss at personal listening, travel and phone calls. Its earcups follow the D-Profile shape Koss uses on this model, and it is offered in black, white, blue and lime. Koss prices it at USD 19.99, and a Limited Lifetime Warranty applies. No batteries are required, since all functions work from the phone or player it is plugged into.

Key specs that matter

Frequency response is 20 to 20,000 Hz, impedance 34 ohms and sound pressure level 94 dB SPL. The drivers are 40 mm dynamic units with neodymium magnets. The cable is straight and dual entry, 1.2 m long, and it terminates in a gold-plated 3.5 mm TRRS plug that carries the microphone signal as well as stereo audio. The headphone weighs roughly 120 to 131 g.

Engineering and use context

The in-line one-touch microphone is omnidirectional and lets the wearer answer calls and play, pause or skip tracks without reaching for the phone. Isolation comes from the closed back of the cups together with ultra soft ear cushions, which Koss credits with keeping outside noise out and the music in. The headband is adjustable, and the durable, low-mass construction is meant for carrying in a bag on daily trips. A flat, tangle-resistant cable is used rather than a round one, which makes it easier to coil for storage, and the dual-entry layout means a separate lead runs into each earcup. The four-conductor TRRS plug is the standard used by current phones and many laptops, so the microphone and remote functions work on most devices with a combined headset socket, and the headphone still plays music through a regular stereo jack.

Pairing

With its low impedance, the UR23i is meant for direct connection to a phone, tablet, computer or portable music player, and Koss states compatibility with most devices through the standard headset connection. A dedicated headphone amplifier is not needed for this type of use. On older equipment with a three-pole socket the microphone will not be active, and hi-fi components with a 6.3 mm output need an adapter.

Alternatives

The Koss UR20 is another closed over-ear Koss model, with a 32 ohm impedance, 97 dB SPL sensitivity and a single-entry cord.