Helix Ci3 T20FM-AL MK2 – 20 mm aluminium dome tweeter
The Ci3 T20FM-AL MK2 is a compact 20 mm tweeter from the COMPOSE i3 series, the price-performance line of the HELIX COMPOSE platform, which combines universal speakers with the advantages of vehicle-specific solutions. Speaker impedances in the series are matched to HELIX and MATCH amplifiers.
Its black aluminium dome balances low moving weight with high rigidity for clear, detailed and natural highs, driven by an efficient neodymium magnet system with linear magnetic flux. Thanks to its very small dimensions it offers several mounting options: flush-mount and angle-mount pods are included, and the tweeter is prepared for car-specific FlexMount20 adaptors and WireKits for installation in the original position.
Key Features
- 20 mm tweeter: 0.75″ tweeter for accurate, detailed high-frequency reproduction
- Black aluminium dome: low weight and high rigidity for natural brilliance and fine detail
- Neodymium magnet: efficient magnet system with linear magnetic flux
- Compact design: small housing allowing several mounting options
- Pods included: flush-mount and angle-mount pods are supplied in the box
- FlexMount20 ready: designed for optional car-specific FlexMount20 adaptors for integration in the original mounting location
- WireKit ready: designed for optional car-specific WireKits – adaptor cables built to automotive standards that connect the speaker to the factory harness or an optional crossover without cutting the original wiring
- Amplifier matching: impedance matched to HELIX and MATCH amplifiers, as for the whole i3 series
Drivers & Construction
- Dome: black aluminium
- Voice coil: 20 mm diameter
- Magnet: neodymium
- Delivered as: pair: 2 × tweeter, 2 × tweeter flush mount, 2 × tweeter pod, 2 × mounting material
Acoustic Performance
- Impedance: 4 Ω (DC resistance 3.2 Ω)
- Sensitivity: 91 dB @ 2.83 V / 1 m; 88 dB @ 1 W / 1 m
- Frequency response: 2,000 Hz – 25,000 Hz
- Resonance frequency (Fs): 1,800 Hz
Crossover
- Recommended high-pass, 6 dB/oct: above 5,000 Hz
- Recommended high-pass, 12 dB/oct: above 3,500 Hz
- Recommended high-pass, 24 dB/oct: above 3,000 Hz
Installation Notes
- Outer diameter: 32 mm / 1.26″
- Installation diameter: 28 mm / 1.10″
- Installation depth: 9.8 mm / 0.39″
- Mounting options: flush mount or angle mount (both pod types included) or car-specific FlexMount20 adaptors
- Accessories named: FlexMount adaptors CFMK20 BMW.1, CFMK20 TES.1, CFMK20 TES.2, CFMK20 POR.1, CFMK20 MB.1; WireKits CWK TES1.T-225TC, CWK TES2.T-225TC, CWK FX.T-550CC
Technical Specifications
| Impedance | Z | 4 Ω |
| DC resistance | Re | 3.2 Ω |
| Frequency response | 2,000 Hz – 25,000 Hz | |
| Resonance frequency | Fs | 1800 Hz |
| Sensitivity | SPL | 91 dB @ 2.83V / 1m 88 dB @ 1W / 1m |
| Voice coil diameter | Ø | 20 mm |
| Cone material | Aluminum | |
| Outer diameter | 32 mm / 1.26″ | |
| Installation diameter | 28 mm / 1.10″ | |
| Installation depth | 9.8 mm / 0.39″ | |
| Recommended crossover frequencies for the highpass | ||
| Slope | Minimum crossover frequency | |
| 6 dB/Octave | > 5,000 Hz | |
| 12 dB/Octave | > 3,500 Hz | |
| 24 dB/Octave | > 3,000 Hz |
Scope of Delivery
2 x Ci3 T20FM-AL MK2
2 x Tweeter flush mount
2 x Tweeter pod
2 x Mounting material
