The Ci5 W165FM-S3 is the 6.5″ midbass from Helix’s Compose i5 range, which sits between the i3 and i7 series and is aimed at a true hi-fi result. It’s an all-rounder, tuned to work in a classic 2-way front stage or as the midbass in a 3-way system. Sold as a pair.

Power handling is 125 W RMS (175 W max), and it runs at 3 Ohms to get the most from Helix and Match amplifiers. Sensitivity is 92 dB at 2.83 V, and it covers 50 Hz to 5,000 Hz. A large 37 mm voice coil keeps thermal compression low and power handling high.

The silicon-coated paper cone is light but very stiff, with excellent damping to suppress unwanted resonances, and a phase plug improves upper-midrange response and reduces compression. The glass-bead reinforced polymer basket is rigid with minimal ringing and keeps the mounting depth to 66.8 mm. The ProConnect terminal takes ordinary speaker cable or Helix’s plug-in WireKits, and the speaker is designed for Helix’s optional FlexMount165 rings for a vehicle-specific fit in the factory location.