Sennheiser CX 300S In-Ear Headphones White

Sennheiser CX 300S are wired in-ear headphones that deliver detailed sound and stronger bass with a one-button smart remote for playback and calls.

Designed by Sennheiser’s audio engineers, the CX 300S combines compact comfort and precise transducer tuning to reveal musical detail while improving low-end punch. The package includes four ear adapter sizes for a tailored seal, a 3.5mm stereo connector for universal compatibility, and an inline smart remote to control music and answer calls without reaching for your device.

How do the CX 300S improve clarity and bass in a small earbud?

Rather than relying on gimmicks, these earbuds use Sennheiser-tuned transducers that prioritize frequency balance and driver control, so vocals and instruments remain clear while the bass is tighter and more controlled. The in-ear design creates a good acoustic seal that reduces outside noise and lets the drivers perform efficiently.

• Precision-tuned drivers for accurate midrange and controlled low frequencies
• In-ear fit enhances passive noise isolation for clearer listening
• Four silicone tip sizes to optimize seal and bass response

Will the inline smart remote work with my phone for calls and music?

The one-button inline remote offers play/pause control and call handling across most smartphones and media players that use a standard TRS headset connection. It’s a straightforward, single-press interface that saves you from unlocking your phone for simple actions.

• One-button control for play/pause and answer/end calls
• Compatible with devices using a 3.5mm stereo headset jack
• No app or pairing—plug in and use immediately

How comfortable are they for long listening sessions?

The CX 300S include four ear tip sizes (XS, S, M, L) so you can find the best fit for longer wear and better isolation. The lightweight, in-ear profile sits snugly without excessive pressure, making them suitable for daily commutes or extended listening periods.

• Four silicone tip sizes for a personalized fit
• Low-mass design minimizes ear fatigue during prolonged use
• Secure in-ear placement helps keep earbuds stable during movement

What connectivity and compatibility should I expect?

The CX 300S are a wired solution that use a standard 3.5mm stereo connector, so they plug into smartphones, tablets, laptops, portable players and other devices with a headphone jack. Because they’re passive wired headphones, there’s no pairing, battery charging, or latency issues to manage.

• Wired connectivity with universal 3.5mm stereo plug
• Works with most phones, computers and audio players that support TRS headsets
• Simple plug-and-play operation with no charging required

Who is this for: The Sennheiser CX 300S suit listeners who want precise, unadorned sound and improved bass in a compact wired earbud, plus the convenience of an inline smart remote. They’re a good match for commuters, students, and anyone who prefers a reliable, no-fuss wired connection with multiple ear tip sizes for a comfortable seal.