In this guide
Helix has expanded its Compose i5 range, and it solves the oldest problem in car audio: fitting proper speakers to a car that was never designed for them. FlexMount adaptors let one driver suit many vehicles, so you get German engineering in a factory-shaped hole.
The FlexMount idea
Traditionally, upgrading speakers meant hunting for a driver that happened to fit your car's aperture, depth and connector. FlexMount inverts that: the driver is designed around a mounting system, and vehicle-specific adaptors handle the rest. The result is a proper fit without hacking at door cards, and a speaker chosen on merit rather than on whether it happened to match the hole.
What's new
The range now covers a full active build. Up top, the Ci5 T25FM-CA tweeters (£124.99). In the middle, M50FM-S3 widebands (£174.99) and M80FM-S3 midranges (£149.99), joined by the new M80FM-D3 CTR centre speaker (£119.99) for cars with a centre channel. We covered the M50FM-S3 and M80FM-S3 in more depth in our Ci5 compact speakers article.
For low end, there's the W165FM-S3 6.5-inch midbass (£199.99), the new W200FM-S3 8-inch woofer, and S200FM hybrid subwoofers (£254.99). There are even BMW and Mini underseat woofers (£309) for cars that put their bass under the seats from the factory.
Why it sounds the way it does
The 3 Ω impedance across much of the range squeezes more usable power out of a given amplifier, and silicon-coated paper cones deliver wideband detail with controlled bass rather than the hard, bright character of cheaper drivers. These are speakers designed to be processed and amplified properly — pair them with a DSP and the difference is substantial.
Our take
This is the range we reach for when someone wants a genuinely high-end system in a car that has to stay looking standard. Tell us your vehicle and we'll work out which adaptors and drivers suit it — and whether a 2-way or full active build makes sense for your budget.
Frequently asked questions
What is FlexMount?
Helix's mounting system — the same driver adapts to different vehicle fitments using model-specific adaptors, instead of needing a different speaker for every car.
Do I need an amplifier for these?
They'll run from a capable head unit, but Compose i5 drivers reward proper amplification and processing. Our amplifier and DSP guides cover the options.
Can you build a 3-way active system with these?
Yes — the range is designed for it, with tweeters, wideband and midrange drivers, midbass and dedicated woofers all available.
Will they fit my car?
That's what FlexMount adaptors are for, and there are vehicle-specific options including BMW and Mini underseat woofers and a Porsche adaptor cable. Send us your car and we'll confirm.
Written by the CEN team in Nottingham — Helix and Audiotec Fischer specialists. Questions? Contact us or call 0115 924 0666.
