Cicada Audio CH65.4V2 — 6.5″ Horn Coaxial Motorcycle Speakers (4Ω)

What’s Inside the CH65.4V2

The CH65.4V2 shares its construction with the CH65.2V2 — all components, materials, and V2 upgrades are identical between the two variants. The only difference is impedance. All construction notes below apply equally to both versions.

The tweeter is an aluminium dome in a horn waveguide with a removable threaded horn flange. The flange unscrews for colour modification — a practical accommodation for custom builds where speaker aesthetics are part of the design. The aluminium dome delivers a bright, low-distortion, extended high-frequency response — harder and more projected in character than a soft dome. On the road: the horn waveguide couples the tweeter’s output more efficiently to the air than a free-air dome, which is the primary reason for the 99 dB sensitivity figure — and why the CH65.4V2 maintains clarity at highway speed where lower-sensitivity drivers struggle.

The mid-bass cone is water resistant treated paper — lightweight, thermally stable, and efficiently coupled to the motor. The 2-inch mid-bass voice coil is wound with Black Coat™ OFC copper, Cicada’s high-conductivity, thermally optimised winding treatment that reduces resistance and handles the thermal load of sustained 250W RMS operation. At 4Ω, the voice coil operates with lower current draw from the amplifier, adding thermal margin to both the driver and the amplifier stage. The 1.4-inch / 36mm aluminium diaphragm high-temp tweeter voice coil completes the signal path with minimal thermal compromise. On the road: consistent mid-bass output and tweeter clarity across a full riding day, without the performance drop that comes from thermal compression in lower-rated voice coils.

The motor is an N35SH neodymium — H-grade temperature rating for sustained thermal stability in a fairing enclosure. The die-cast aluminium basket with Vortex Flow Venting™ channels airflow through the motor to manage heat at high output levels.

Shortening Ring — What It Does

A shortening ring (Faraday ring) is a conductive ring fitted around the pole piece of the motor. As the voice coil moves, its inductance varies — and inductance variation causes non-linear distortion and blurs transient detail, particularly at higher output levels where coil excursion is greatest. The shortening ring creates a mirror current that opposes and cancels the inductance variation, holding the voice coil’s electrical behaviour more linear across the excursion range. The practical result is lower distortion at high output and tighter, more controlled transient response. On the road: at volume levels where other 6.5-inch drivers start to blur and compress, the CH65.4V2 remains controlled.

Bi-Amp Capability

The CH65.4V2 supports bi-amplification — the horn tweeter and mid-bass cone can be driven from separate dedicated amplifier channels. In a bi-amp configuration, the passive crossover is bypassed (or supplemented by the active crossover in a DSP), and each driver receives its own dedicated channel with independent level, time alignment, and gain control. For builds using a DSP amplifier with per-channel processing at 4Ω, bi-amping the CH65.4V2 gives full control over the tweeter level and timing relative to the mid-bass. Confirm crossover point and channel assignment with your DSP before wiring.

Crossover and Tweeter Attenuator

The external 12 dB crossover crosses over at 4 kHz with a 12 dB/octave slope. It includes an optional tweeter attenuator resistor — a passive component that reduces tweeter output level relative to the mid-bass. On a Street Glide fairing where the upper midrange is already acoustically reinforced by the enclosure geometry, or for riders who prefer a less prominent treble balance, the attenuator resistor can be installed at the crossover to reduce tweeter level without EQ. Default configuration runs without it; the attenuator is a field-adjustable option at installation.

Sensitivity — What 99 dB Means in Practice

At 99 dB (1W/1m), the CH65.4V2 is among the most sensitive 6.5-inch motorcycle coaxials available. The gap between 99 dB and a conventional 91 dB motorcycle speaker is 8 dB — requiring the 91 dB speaker to use approximately 6.3× the amplifier power to match the CH65.4V2’s output at 1W. In a bridged amplifier configuration where per-channel power is already elevated, the 99 dB sensitivity means that elevated power translates into proportionally more SPL. For a Harley at highway speed where 85–95 dB of ambient noise is normal, the sensitivity advantage of the CH65.4V2 is what makes the system audible over the environment.

Why 4Ω — Bridged Amps and Thermal Margin

A 4Ω speaker presents a higher electrical load to the amplifier than a 2Ω speaker — lower current demand, less heat generated, and more tolerance for wiring impedance variation. For bridged amplifier configurations — where two amplifier channels are combined to drive a speaker pair at higher per-channel output — the 4Ω load satisfies the minimum impedance requirement on most motorcycle amplifiers including the FLX500.4 and FLX700.4. For stereo installs at the amp’s rated 2Ω output, the CH65.2V2 (2Ω) is the matching choice.

Fitment

• Designed for 2014+ Harley-Davidson factory 6.5-inch speaker positions.
• Harley-Davidson Street Glide (2014+): Batwing fairing lower speaker positions.
• Harley-Davidson Road Glide (2014+): Fairing speaker positions.
• Lower Fairing (Road Glide® 2015–2023): Factory lower fairing speaker positions.
• Harley-Davidson Ultra Limited (2014+): Fairing and lid positions.
• Harley-Davidson CVO models (2014+): Factory 6.5-inch speaker positions.
• Mounting Depth: 76 mm (3.0 in). Mounting Diameter (cutout): 145 mm (5.7 in).
• Compatible with 4Ω-rated amplifiers including bridged configurations — FLX500.4, FLX700.4, and other 4Ω-stable motorcycle amplifiers.

Technical Specifications