BMW i3 Premium Speaker System | HELIX Ci7100 | Premium Tweeters

The premium 2-way replacement speaker system for BMW i3/i3S.

The speaker system consists of a high-end 100mm mid-bass driver with vehicle-specific adaptation, plug & play connection adapter, and a 25mm premium tweeter in a 3D-printed surface-mount enclosure. The enclosure clips onto the inside of the mirror cover, positioning the tweeter neatly and precisely in your BMW i3! Installation is simple and requires no wiring.

The system is based on the HELIX COMPOSE i7, which represents uncompromising high-end performance for an extravagant in-car sound experience.

With a clear influence from its high-end sister brand BRAX, the i7 speaker series is entirely "made in Germany" and optimized for pure musical enjoyment. It is combined with our premium NT25S tweeter. Supplied with a customized crossover and BMW i3 adapter.

Features

• 2-way high-performance speaker kit, which combines unique sound characteristics with versatile integration options
• High efficiency and 3-ohm technology for maximized amplifier power output
• Sophisticated automotive-grade connectors for a secure, reverse-polarity-independent connection – COMPOSE Connect & FlexConnect

Tweeter

• Premium NT25S - 22mm fabric dome tweeter with coupling volume
• 22mm dome for optimal dispersion and frequency response
• Coupling volume for low fs and reduced distortion
• Outer ring neodymium magnet
• Precisely coated textile diaphragm
• Optimized dome shape for wide frequency range
• Ventilated voice coil former for reduced distortion and compression
• Cup-clad aluminum voice coil wire
• fs: 825Hz, dB(2.83V): 89.5dB/1m, 4Ohm, 65W (HP 2.5kHz/12dB/Oct.)
• 3D printed enclosure for BMW i3/i3S

Midrange speaker

• 100 mm high-end midrange speaker, combining unique sound characteristics with versatile integration options

• High efficiency and 3-ohm technology for maximized amplifier power output
• Ultra High Damping paper cone for excellent impulse response and unsurpassed frequency response
• Glass bead reinforced high-tech polymer composite basket for maximum rigidity and minimal resonances
• Specially shaped rubber surround for large linear cone excursion
• Polyurethane dome (dustcap) for optimizing the frequency response in the upper midrange
• 25 mm voice coil for minimal thermal compression and high power handling
• Powerful Push-pull neodymium magnet system for particularly high efficiency and minimal distortion
• Adapted mounting adapter with cable adapter for BMW i3/i3S

Crossover

• High-quality, separate crossover with compact dimensions for easy installation
• 6-stage tweeter level adjustment with integrated tweeter protection for optimal adaptation to the installation position
• Extensively tuned – with a 12 dB slope for the tweeter
• Reversible connection to the original vehicle wiring harness

Technical Data

Power handling RMS / Max.	P	100 / 150 Watt
Impedance	Z	3 Ω
DC resistance	Re	3.0 Ω
Frequency range		110 Hz - 7,000 Hz
Resonance frequency	Fs	85 Hz
Mechanical quality	Qms	4.58
Electrical quality	Qes	0.52
Overall quality	Qts	0.47
Compliance	Cms	590 µm/N
Equivalent volume	Vas	2.5 L
Force factor	B*I	4.3 Tm
Efficiency	SPL	91 dB @ 2.83V / 1m 87 dB @ 1W / 1m
Membrane area	Sd	55 cm²
Moving mass	Mms	5.9 g
Membrane material		UHD (Ultra High Damping) paper membrane
Mechanical resistance	Rms	0.69 kg/s
Voice coil diameter	ø	25 mm
Voice coil winding width		5.5 mm
Max. linear diaphragm stroke	Xmax	+/- 1.3 mm
Outer diameter	ø	98 mm
Outer diameterwith universal mounting ring	ø	104.5 mm
Installation diameter	ø	89 mm
Crossover		Tweeter: 12 dB high-pass filter, tweeter protection and level adjustment