Helix Compose Basic CB C87.2-S3 Coaxial Speaker Kit 3.4 Inch 8.7cm 40w RMS Pair
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The Helix Compose Basic CB C87.2-S3 is a 3.4 inch (87 mm) 2-way coaxial car speaker pair from the Helix Compose range, handling 40W RMS with a 3 ohm impedance and a 13 mm PEI dome tweeter.
Key specifications
- Size: 3.4 inch / 87 mm coaxial, sold as a pair
- Power handling: 40W RMS
- Impedance: 3 ohms
- Tweeter: 0.5 inch / 13 mm PEI dome, neodymium magnet
- Midrange cone: polypropylene, steel basket with ventilation holes
- Crossover: integrated, 6 dB slope
- In the box: 2 x CB C87.2-S3, 1 x mounting material
Helix Compose — universal speakers evolved
The Helix Compose platform was developed to meet the demands of modern vehicle installation. It combines proven universal speaker design with the precision of vehicle-specific systems, under the principle of "developed inside the vehicle, for the vehicle". The result is high efficiency, strong sound quality and broad vehicle compatibility.
The essentials for an exceptional sound experience
The Compose Basic range is the entry point into the Helix Compose system. All components are designed to work together and pair well with Helix and MATCH amplifiers for consistent performance. The Basic tweeter also features smart mechanical connection technology for safe, professional installation.
High efficiency
Helix Compose uses 3 ohm technology across the range, designed to work with Helix and MATCH amplifiers and deliver a clear gain in efficiency and maximum sound pressure. Some models are available as optional 2 ohm variants for maximum output when paired with a suitable amplifier — for example, the Helix Compose i3 Ci3 K100.2FM-S3 4 inch FlexMount component speakers show how the Compose range extends across different formats and power levels.
Powerful bass, always on point
The Compose Basic bass-midrange driver uses a lightweight polypropylene diaphragm for strong sound performance. The steel basket includes additional ventilation holes for improved cooling, and a powerful magnet system ensures accurate impulse response. A soft polyurethane dustcap optimises frequency response in the upper midrange. The compact form factor suits installation in tight spaces.
High-frequency reproduction with unique dynamics
The Basic tweeter uses a PEI dome and a highly efficient neodymium magnet for dynamic high-frequency reproduction and clear, detailed sound.
Explore the full range in Helix Compose Basic.
Specification
| Size | 3.5 Inch |
|---|---|
| Shape | Round |
| Type | Coaxial |
| Series | Compose Basic |
| Article Number | CB22310 |
| Country of Manufacture | China |
More specs
| |
What's Included
- 2 x CB C87.2-S3
- 1 x Mounting material
Helix
About the Helix CB22310
From our tech experts at CEN
Helix Compose Basic 3.4 inch coaxial speakers, with the tweeter mounted in the centre of the woofer, rated at 40w RMS.
Who it suits
Drivers replacing tired factory speakers who want a clear improvement without relocating tweeters.
Our tech experts advise
Sizes, adapter rings and harnesses vary by vehicle, year and trim, so we confirm what your car takes before ordering rather than guessing. Door treatment and tweeter placement change the result as much as the speaker does. Installation and tuning are priced per vehicle, so get in touch with your make, model and year and we will confirm what it needs. See car audio installation.
Explore the full Helix range at CEN, with fast UK dispatch and expert advice from our Nottingham team. Shop all Helix
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Have it Fitted By Our Team
Our team fits car audio, stereos, dash cams and vehicle security at our workshop in Beeston, Nottingham. Tell us your vehicle and we'll confirm the parts and a fitted price.
- 1
Tell us your vehicle
Make, model and year, and what you'd like fitted.
- 2
We confirm the parts
Fascia, wiring and interfaces checked for your car, with a fitted price.
- 3
Fitted at our workshop
Bring it to our Beeston workshop and we do the rest.
Unit 25 Technology Drive, Beeston, Nottingham NG9 1LA
More from Helix Compose Basic
More options from the same range, in stock and ready to go
Helix Compose Basic CB K130.2-S3 FlexMount Speaker Kit 5 Inch 13cm 70w RMS Pair
£179.99
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Helix Compose Basic CB C130.2-S3 Coaxial Speaker Kit 5 Inch 13cm 70w RMS Pair
£104.99
Helix Compose Basic CB C460.2-S3 Coaxial Speaker Kit 4x6 Inch 50w RMS Pair
£104.99
Helix Compose Basic CB W165-S3 Midbass Speaker Kit 6.5 Inch 16.5cm 80w RMS Pair
£119.99
Helix Compose Basic CB C570.2-S3 Coaxial Speaker Kit 5x7 Inch 70w RMS Pair
£119.99
Frequently Asked Questions
Q: Will these speakers fit my car?
A: Most car speakers are standard sizes, but mounting depth and fitting rings vary by vehicle. Check the size in the Specification tab against your vehicle, or contact CEN with your registration and we will confirm fitment and any adapters or fitting kits you need.
Q: Do I need an amplifier to run these speakers?
A: Not always. Most speakers will run from a standard head unit, but a dedicated amplifier lets them perform at their best, particularly for component sets and higher power handling models. The RMS figure in the Specification tab is the guide to how much clean power they can use.
Q: What is the difference between coaxial and component speakers?
A: Coaxial speakers combine the tweeter and woofer in one unit for a simple like-for-like upgrade. Component sets separate the tweeter and woofer with a crossover for better imaging and detail, and suit installs where sound quality is the priority.
Q: Do these come as a pair?
A: Unless stated otherwise, car speakers are sold in pairs. Check the product title and What's Included tab, which lists exactly what is in the box.
Q: Can CEN fit these speakers for me?
A: Yes. CEN offers professional installation from our Nottingham premises. Contact us to book an installation slot or ask for a fitting quote.
Q: What size is the HELIX CB C87.2-S3?
A: It is a 3.4 inch (87 mm) 2-way coaxial speaker, sold as a pair.
Q: What impedance is the HELIX CB C87.2-S3 and will it work with my head unit?
A: It is a 3 ohm speaker. 3 ohm technology raises efficiency and maximum sound pressure, and it is matched to HELIX and MATCH amplifiers. It handles 40W RMS, so a dedicated amplifier lets it perform at its best.
Q: What tweeter does the CB C87.2-S3 use?
A: A 0.5 inch (13 mm) PEI dome tweeter with a neodymium magnet, high-passed by an integrated 6 dB crossover.
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