Sennheiser CX 300S Black
Sennheiser transducer technology delivers detailed sound with enhanced bass through a 17Hz-21kHz frequency response, while the ergonomic in-ear design provides passive noise isolation. The heavy-duty, tangle-free cable and built-in one-button remote with microphone add practical durability and call control at an accessible price point. This wired headset is best for budget-conscious listeners who prioritize clear audio and reliable build quality for daily commutes and calls.
Snapshot
The 30-Second Version
Fantastic sound and all-day comfort in a budget wired package, but the build quality is a total crapshoot. Buy them for the audio, but keep the receipt.
Pros & Cons
Pros
- Incredibly comfortable for hours of wear 95th
- Clear, balanced sound that's rare at this price 73rd
- The tangle-free cable is a genuine lifesaver 72nd
- Multiple ear tip sizes for a perfect seal 66th
Cons
- Build quality is a coin flip, durability is a real concern
- Bass response can be inconsistent between units
- Mic quality is just mediocre for calls
- No active noise cancellation, just passive isolation
What owners think
The Word on the Street
How owner sentiment changed over time
ExclusiveBased on when customers actually wrote their reviews - so you can see whether early praise held up.
Based on 12 dated customer reviews, grouped by calendar quarter. Period analysis is in English.
The proof
Performance
The sound profile is what surprised us most, landing in the 72nd percentile. It's a strong, clear presentation with a focus on detail rather than just blasting you with muddy bass. The 17Hz low end is present, but don't expect skull-rattling sub-bass. It's a refined, balanced listen that punches above its price for music and podcasts. The real shocker, though, is the comfort. At the 95th percentile, these things just disappear in your ears, making them perfect for long listening sessions.
Specifications
Full Specifications
Design
| Form Factor | in-ear |
| Wearing Style | ear-tip |
| Ear Tips | XS, S, M, L |
| Weight | 0.0 kg / 0.0 lbs |
Audio
| Freq Min | 17 |
| Freq Max | 21000 |
| Impedance | 18 |
| Sensitivity | 118 |
Noise Control
| ANC | No |
| Transparency | Yes |
Connectivity
| Wired Connector | 3.5mm |
Earbud Battery
| Charging | proprietary |
Case Battery
| Case Charging | proprietary |
Microphone
| Microphone | Yes |
Features
| Touch Controls | Yes |
vs Competition
The CX 300S sits in a weird spot. It's a wired bud in a wireless world. If you need ANC and true wireless freedom, the Sony WF-C700N is the obvious upgrade, but it costs significantly more. The Soundcore P31i also offers a wireless experience with more features for a similar price to the higher CX 300S listings. But if you just want a cheap, great-sounding wired backup that never needs charging, the Sennheiser still makes a strong case against any budget wireless bud.
| Spec | Sennheiser CX 300S Black | Samsung Galaxy Buds3 Pro | Sony WF-C700N WFC700N/B | Soundcore P31i | Nothing Ear (3) | EarFun Air Pro 4+ |
|---|---|---|---|---|---|---|
| Form Factor | in-ear | in-ear | in-ear | in-ear | in-ear | in-ear |
| Driver Type | - | dynamic | dynamic | dynamic | dynamic | hybrid |
| Wireless | - | true | true | true | true | true |
| Active Noise Cancellation | false | true | true | true | true | true |
| Bluetooth Version | - | 5.4 | 5.2 | 6.0 | 5.4 | 6.0 |
| Battery Life Hours | - | 6 | 15 | 10 | 10 | 12 |
| Case Battery Hours | - | 26 | 15 | 50 | 19 | 54 |
| Water Resistance | - | IP57 | IPX4 | IP55 | Water-Resistant | IP55 |
| Multipoint | - | true | true | - | true | true |
| Compare | Compare | Compare | Compare | Compare |
| Product | Anc | Mic | Build | Sound | Battery | Comfort | User Sentiment | Connectivity | Social Proof |
|---|---|---|---|---|---|---|---|---|---|
| Sennheiser CX 300S Black | 66.1 | 44.1 | 35 | 71.5 | 48.8 | 94.7 | 20.4 | 49.3 | 73.1 |
| Samsung Galaxy Buds3 Pro Compare | 97.4 | 97.4 | 98.9 | 93.5 | 77 | 94.7 | 80.1 | 99.7 | 90.3 |
| Sony WF-C700N WFC700N/B Compare | 97.4 | 83.9 | 81.4 | 82.9 | 82.1 | 73.8 | 97.3 | 89.9 | 73.1 |
| Soundcore P31i Compare | 90.7 | 97.4 | 92 | 97.4 | 93.7 | 73.8 | 97.3 | 87.5 | 90.3 |
| Nothing Ear (3) Compare | 93.5 | 97.4 | 73.3 | 93.9 | 77.9 | 94.7 | 80.1 | 100 | 81.5 |
| EarFun Air Pro 4+ Compare | 97.4 | 97.4 | 92 | 99.8 | 96 | 73.8 | 97.3 | 99.4 | 90.3 |
Price
Value & Pricing
The value story is weird here. Prices are all over the map, from a sensible $29 to an insane $1,001. Ignore the crazy listings. If you can snag these for around $30, they're a steal. The sound and comfort you get for that price is fantastic. Just know you're rolling the dice on how long they'll physically hold together.
Amazon 3 offers From $29
Newegg 1 offer From $78
Price History
Read more
Overview
The Sennheiser CX 300S is a classic wired IEM that refuses to die, and for good reason. For under fifty bucks, you're getting that signature Sennheiser sound, a surprisingly comfortable fit, and a tangle-free cable that actually lives up to the name. The one thing to know? The sound is clear and balanced, but the build quality is a gamble. Some pairs last for years, others fall apart in months.
Common Questions
Q: Do these have a microphone and remote?
Yes, there's a one-button smart remote and mic on the cable. It handles play/pause, calls, and track skipping. The mic quality is just okay for calls, nothing special.
Q: Are these good for working out?
Honestly, no. Our data shows fitness is their weakest area. They're not water-resistant, and the cable will get in the way. Grab some cheap wireless buds with an IPX rating for the gym.
Q: Do they block out noise?
They offer passive noise isolation thanks to the in-ear seal, which is decent for reducing background hum. But there's no active noise cancellation, so they won't silence a loud commute.
Who Should Skip This
If you're looking for a durable, daily-driver headphone that can survive a beating in your bag, this isn't it. The build quality is the biggest letdown here. Go get something like the Soundcore P31i or spend more on a pair with a proven rugged build instead.
Verdict
Buy these for the sound and comfort, not the durability. The Sennheiser CX 300S delivers an audio experience that's way better than its price suggests, and they're one of the most comfortable pairs of earbuds we've ever tested. Just treat them gently, and maybe don't make them your only pair if you're rough on your gear. For a cheap wired backup or a first step into decent audio, they're a solid recommendation with a big asterisk.
