Sennheiser CX 350BT Wireless Neckband (Black)

Sennheiser CX 350BT Wireless Neckband (Black)

The Sennheiser CX 350BT is a Bluetooth in-ear headphone in the neckband style: the two earbuds are joined by a soft band that rests around the neck, with an in-line remote and microphone on the cable. The earbuds are always within reach, and there is no charging case to carry or lose. This listing is the Black version.

Sound is handled by 9.7 mm dynamic drivers, and the codec support is broader than most at this level: alongside SBC and AAC, the CX 350BT supports aptX and aptX Low Latency. On compatible devices, aptX Low Latency keeps audio in sync with the picture, which matters for video and gaming. Battery life is rated at up to 10 hours, with USB-C charging.

Key features

• Bluetooth 5.0 with multi-pairing for two devices
• Codec support: SBC, AAC, aptX and aptX Low Latency
• Up to 10 hours of battery life, USB-C charging
• 9.7 mm dynamic drivers
• Dedicated voice assistant button for Siri or Google Assistant
• Sennheiser Smart Control app with equaliser and podcast mode
• Four sizes of ear tips for a secure, isolating fit
• Lightweight 12 g neckband design

Sound and the low-latency advantage

The frequency response runs from 17 Hz to 20,000 Hz, with 28 ohm impedance and a sound pressure level of 112 dB, so any phone drives it to comfortable levels with ease. Total harmonic distortion is below 0.5 percent. The tuning follows the house approach: clear, detailed presentation with a solid bass foundation rather than exaggerated low end. The Low Latency mode is the feature video watchers will notice most, removing the lip-sync drift that makes dialogue feel wrong on lesser earphones.

Fit and isolation

Four sizes of ear tips, from extra small to large, are supplied. Choosing the right size does two jobs at once: it seals the ear canal for full bass response, and it provides the passive noise isolation that makes music and calls clearer in traffic, offices and trains without any electronic cancelling. The neckband keeps the cable off your chest and the buds hanging ready at collar level, and at 12 g the whole system is light enough to wear through a full working day.

Controls, calls and the app

The in-line remote handles music playback, volume and calls, with a microphone covering 100 Hz to 8,000 Hz for speech. A separate button summons Siri or Google Assistant directly. Multi-pairing keeps two devices connected at once, so you can listen on a laptop and still take a phone call without re-pairing. Through the Sennheiser Smart Control app you can adjust the equaliser to taste, switch on podcast mode for clearer speech, check battery status and receive firmware updates.

Battery and charging

Ten hours of playback covers a long workday or a full day of travel between charges, and charging is by USB-C, the same cable as most current phones. The built-in 100 mAh lithium polymer battery keeps standby time long when the earphones are idle. There is no case battery to manage; the neckband itself is the whole product, which is precisely the simplicity its users value.

For listeners who like the neckband form and want proper codec support, reliable Bluetooth and sound tuned by an established headphone maker, the CX 350BT in Black remains a sensible, fuss-free daily companion.