Cicada Audio FLX1000.4 — High-Power 4-Channel Class-D Motorcycle Amplifier (1,000W RMS / 254W x4 @ 2Ω)

Power Output — What the Numbers Mean

The FLX1000.4 is rated at two supply voltages, which matters for real-world motorcycle installs where charging voltage varies with RPM and electrical load. At 14.4V — a fully charged, engine-running system — the amp delivers 168W × 4 at 4Ω and 254W × 4 at 2Ω. At 12.5V — closer to battery voltage under heavy load — output drops to 150W × 4 at 4Ω and 220W × 4 at 2Ω. The 2Ω figures drive the product name: 254W × 4 yields approximately 1,000W total RMS at rated voltage.

Bridged, the amp produces 530W × 2 at 4Ω at 14.4V (461W × 2 at 12.5V) — the configuration for a high-output two-channel front stage, a mid-bass enclosure, or a compact subwoofer application where maximum per-channel power is the priority.

Crossover and Signal Control

The FLX1000.4 runs HPF, LPF, or Full Range crossover modes with a frequency range of 30 Hz – 300 Hz and a fixed 12 dB per octave slope. This covers the primary use cases for a high-power 4-channel motorcycle amp — high-pass filtering for fairing speakers, low-pass filtering for a rear mid-bass or subwoofer channel, and full-range operation for coaxial speakers.

The 12 dB/octave slope is well-matched to coaxial and mid-bass builds. For builds that require steeper driver-separation slopes — separating dedicated horn tweeters and midrange drivers where 24 or 48 dB/octave gives cleaner isolation — the FLX700.4's crossover architecture handles that role more precisely. The FLX1000.4 is the high-output choice for coaxial and mid-bass builds where headroom and current delivery matter more than multi-octave crossover flexibility.

Input sensitivity runs 0.2V – 12V, covering both OEM Harley signal levels and standard RCA output from aftermarket head units.

Built for the Motorcycle Environment

The circuit board is conformal coated — a protective film sealing the electronics against moisture, humidity, and vibration-borne dust — and the whole amplifier is encased in an extruded aluminium heatsink chassis. On the road: road spray, humidity swings, and constant vibration are the normal operating environment for a fairing- or bag-mounted amp, not an edge case — this is the packaging that survives them.

The ICAD overload protection circuit guards the output stage against short circuits, thermal overload, and wiring faults, and two indicators handle the diagnostics: a power/protect LED that shows blue in normal operation and red in protect mode, and a dedicated clip LED that should only flash on musical peaks. If the clip LED holds solid for more than 2–3 seconds, back the volume or gain off. On the road: gain setting and fault-finding by eye — a shorted speaker wire or an overheating amp announces itself before it becomes a failure.

The crossover and gain potentiometers are detented — they click through fixed positions rather than sweeping freely, so settings are exact, repeatable, and immune to vibration drift. On the road: the crossover point set in the workshop is still the crossover point after a corrugated highway — and a known-good tune can be replicated on a second bike click-for-click.

Power and ground run through busbar-style terminals accepting up to 4 AWG wire, with 12 AWG busbar speaker terminals that clamp solid on bare speaker wire — no crimped pins to work loose under vibration. Signal input is via Molex® connectors, hooking up through standard RCA or H-D custom-terminated harnesses, and the speaker-output side can run plug-and-play through the HDFLXFO front and HDFLXRO rear H-D speaker output harnesses.

Mounting Options

Every FLX amplifier ships with two sets of mounting brackets: standard brackets (preinstalled) for flat-surface mounting, and inverted brackets that mount the amp top-face down — keeping the cooling fan on fan-equipped models facing downward with proper airflow clearance. The brackets carry multiple mounting points and can be trimmed or modified to suit a specific fairing, amp rack, or bag install without compromising structural integrity. Where there is no surface to screw into, the included 3M® locking velcro, zip ties, or straps secure the chassis directly. For 2024+ Road Glide® and Street Glide®, the model-specific 24HDAR-RG and 24HDAR-SG single-amplifier mounting systems bolt an FLX amp into the fairing without custom fabrication. On the road: the amp adapts to the space the bike actually has — factory amp tray, amp rack, or a tight custom cavity — rather than dictating it.

System Integration

The FLX1000.4 accepts high-level speaker output from the factory Harley Boom! Box radio directly — no additional converter required for 2014–2023 models — or low-level RCA from any aftermarket head unit.

Turn-on supports REM and DC offset modes. DC offset turn-on is useful on older Harley platforms where routing a clean remote wire to the factory head unit is not practical.

At 60A music-level current draw, the FLX1000.4 operates at the upper limit of most factory Harley charging systems. Maximum draw is 116A; a 120A fuse is recommended on the power feed. For builds pairing the FLX1000.4 with additional amplifiers or high-draw accessories, verify total system current load against the bike's alternator output before finalising the design.

The FLX1000.4 does not include onboard DSP. For builds requiring time alignment, multi-band EQ, or advanced signal routing, pair with a dedicated DSP processor upstream of the amp inputs.

A 2ch/4ch input switch lets channels 1/2 feed all four outputs from a single stereo pair — no external Y-adapters needed when running a 2-channel source into a four-channel or bridged configuration. For bikes retaining the factory Harley amplifier, Cicada's HDFiMY or HDFiM56Y-1.5 harness handles the OEM amplifier connection.

Wiring matters at these current levels: use properly sized OFC (oxygen-free copper) power and ground wire only — never CCAW (copper-clad aluminium), which carries less current for the same gauge and heats under sustained draw — and locate the main fuse within 457 mm (18") of the battery terminal.

2024+ Platform Notes

For 2023.5 CVO and 2024+ Harley-Davidson Touring models running Skyline OS, the FLX1000.4 can be integrated as part of an aftermarket audio system when paired with a NAV-TV ZEN-H or ZEN-H Pro. The ZEN-H / ZEN-H Pro handles the Skyline OS signal interface — the FLX1000.4 then receives the processed output and powers the speakers downstream from it. Without a NAV-TV ZEN-H or ZEN-H Pro, integration with a 2023.5 CVO or 2024+ Harley is not supported. For 2014–2023 models (excluding 2023.5 CVO), the high-level input connects directly to the factory Boom! Box radio.

Fitment

• Harley-Davidson Street Glide: Batwing fairing — fits standard fairing amp tray.
• Harley-Davidson Road Glide: Sharknose fairing — fits standard amp tray positions.
• Harley-Davidson Ultra Limited / Ultra Classic: Fits fairing amp rack positions.
• Harley-Davidson CVO models: Fits fairing amp rack (see 2024+ note above for Skyline OS bikes).
• Harley-Davidson Trike: Compatible — fits fairing, trunk, or saddlebag amp rack positions.
• Compatible with OEM Boom! Box radios (high-level input) and all aftermarket head units (high-level or RCA inputs).
• Run 2Ω speakers for maximum rated output; 4Ω for bridged applications.

Technical Specifications