Reference Series · Build Guide
Harley Audio Upgrade Stages Explained: Speakers, Amp and DSP
Quick answer: This is MAA's practical framework for planning a Harley audio system, not a universal industry standard (manufacturers and installers use "stage" terminology differently). Stage 1 is a compatible speaker upgrade on existing power. Stage 2 adds an external amplifier. Stage 3 adds dedicated DSP control, whether the DSP is built into the amplifier or a standalone unit. Beyond that is custom and competition territory: active multi-way systems, multiple amplifiers, subwoofers, fabrication and electrical upgrades. Pick the stage that matches how you ride.
"Stage 1, Stage 2, Stage 3" is common shorthand, but different manufacturers, dealers and riders use it differently, so treat what follows as MAA's framework for thinking about a build rather than a fixed definition. Each stage changes something real about what the system can do. Here is what each delivers and how to decide which suits your riding.
Stage 1: The Speaker Upgrade
Stage 1 is replacing the factory speakers with compatible aftermarket units on existing power: no amplifier, no DSP, just better speakers in the same positions running from the factory head unit or amplifier.
What changes: the most noticeable improvement is clarity and detail at low to moderate volume. Factory speakers are often built to a cost point with paper cones and basic tweeters. Aftermarket speakers such as the Cicada CX (IMPP cone) or CXX (Kevlar cone) use better cone materials, tweeter designs and higher-temperature surrounds and baskets, so the sound is cleaner and voices more intelligible.
What does not change: volume headroom at highway speed. The existing factory amplification (the radio's internal amplifier, or a separate factory amplifier where fitted) is limited, and on open-air highway riding it runs out of clean headroom against wind and road noise. A Stage 1 system sounds meaningfully better in suburban and low-speed riding, but at sustained highway speed you will still push the factory power to its limits.
Stage 1 speaker selection: the CX range in the fairing and saddlebag lids is a natural starting point. If you know an amplifier is coming, the CXX range is worth choosing now, because it handles higher power cleanly when you step up, while the CX range is optimised for lower factory power.
Who it suits: riders who listen mostly at low to moderate speed, mainly stream over Bluetooth, want a noticeable improvement without extra hardware, or want to settle speaker preference before committing to a full system.
Stage 2: Speakers Plus an Amplifier
Stage 2 adds an external amplifier to the speaker upgrade. This is where the system becomes genuinely capable at highway speed, and in MAA's experience it is the change most riders describe as making the biggest difference.
What changes: clean headroom. The Cicada FLX700.4 delivers 120 watts RMS per channel at 4 ohms (175W at 2 ohms). As a simple example, moving from roughly 40W to 120W per channel triples the available electrical power, but it does not sound three times as loud, and the actual factory-to-aftermarket comparison depends on the radio, amplifier and audio package fitted to the bike. The audible gain from more power is far smaller than the watt ratio suggests, and speaker sensitivity, distortion and positioning matter just as much as raw power.
Reading the specs: RMS output is measured under specified voltage, load and distortion conditions; peak or max power is a momentary lab figure that is not useful for comparison unless the method is defined. Always compare by RMS. See the amplifier guide and how to match speakers and amplifiers.
Stage 2 amplifier examples:
- FLX700.4: 120W per channel at 4 ohms. A common starting point for 4-speaker Harley builds, commonly used with CXX65 and CXX69 speakers, subject to the motorcycle's charging output, wiring and use pattern.
- FLX1000.4: 168W per channel at 4 ohms. More headroom for regular highway distances.
Stage 2 speaker pairing: running CXX65 in the fairing and CXX69 in the saddlebag lids with an FLX700.4 is a popular Stage 2 build that covers all four positions and is within reach of most riders, subject to the bike's charging output and wiring.
Who it suits: riders who spend regular time at highway speed and want the system to keep up. In MAA's experience, the jump from Stage 1 to Stage 2 is the single most significant performance improvement, and it is where many riders settle.
Stage 3: Speakers, Amplifier and DSP
Stage 3 adds dedicated DSP control to the amplified system, whether the DSP is built into the amplifier (an FLX PRO model) or a standalone processor. The DSP gives precise control over EQ, crossover frequencies, arrival-time alignment and output levels, so the speakers work together as a coherent system rather than four independent drivers.
What changes: the quality of the sound, not just the quantity. You can set EQ per position to suit an open fairing and helmet, and you can use delay to improve arrival-time alignment between speaker locations. It is worth being precise here: delay improves relative arrival time, it does not make all sound reach you "in phase," because phase varies by frequency and is also affected by crossovers, polarity and acoustic distance. Crossover, polarity and phase adjustments manage how drivers combine through their shared frequency ranges. Set correctly, the result is a system that sounds deliberate rather than a collection of well-specified parts.
Stage 3 options (integrated or standalone DSP):
- FLX1400.4PRO: high-output amp with built-in DSP, 225W per channel at 4 ohms. The integrated route to Stage 3 in a single unit.
- FLX1000.4 or FLX1400.4 plus HKI Mini DSP: a standard amplifier with a compact standalone DSP. It adds multi-channel processing and software tuning; confirm the current channel count, sample rate, tuning method and weather protection on the product page.
- FLX1400.4 plus DSP412PRO: for builds with more channels, or where a published IP65 rating for the processor matters. Its up-to-12 outputs and IP65 rating suit complex or exposed installations.
Stage 3 speaker pairing: CHX65 horn coaxials in the fairing and CHX69.2 in the saddlebag lids with an FLX1400.4 and a DSP. The horn coaxials benefit from the extra headroom and from DSP crossover control. This is a full-capability touring system: capable of strong sustained highway output when correctly matched, limited, installed and supported by the electrical system, and tuned rather than just connected.
Who it suits: riders who do significant highway distance and want the best from the platform, and riders who have completed Stage 2 and want to hear what proper tuning does.
Beyond Stage 3: Custom and Competition
Some builds go further: separating woofer and tweeter onto independent amp channels (active), running multiple amplifiers for different zones, or adding a subwoofer, often with Tour-Pak enclosures, lower-fairing subs or bespoke fabrication. These need more amp channels and DSP outputs, and may need an electrical upgrade to support the total current draw, though that is not automatic. Whether a battery or charging upgrade is required depends on the current draw, charging capacity, amplifier efficiency, use pattern and engine speed. If your build is heading here, a phone consult to design the architecture first is the sensible starting point.
Stage Comparison at a Glance
| Stage | Components | Tier | Highway performance |
|---|---|---|---|
| Stage 1 | Compatible speakers on existing power | Entry | Better clarity; still limited by factory power at speed |
| Stage 2 | Speakers plus external amplifier | Mid-level | Significantly more headroom; can be genuinely capable at highway speed when correctly matched, filtered, installed and electrically supported |
| Stage 3 | Speakers, amplifier and DSP (integrated or standalone) | Premium | Tuned, arrival-time aligned, full parametric EQ |
| Beyond | Active, multi-amp, subs, fabrication | Custom | Bespoke; designed per build |
For current Australian pricing by stage, see the Harley audio upgrade cost guide. Costs vary with the speaker range, amp model and whether DSP is integrated or standalone, and do not include installation.
Frequently Asked Questions
Can I skip Stage 1 and go straight to Stage 2?
Often yes, if budget allows. Stage 1 without an amplifier is limited by factory power, so if you are planning an amp eventually, buying the speakers and amp together (and choosing speakers rated for the amp's output) gives a better result from day one and can avoid selecting a lower-power speaker that does not suit the planned amplified system. The CXX and CHX ranges are designed to be driven by amplifier power, so starting with them at Stage 2 is the logical order.
How much does DSP actually improve a Stage 2 system?
Usually more than riders expect. A Stage 2 system is already much better than factory; adding a properly tuned DSP with arrival-time alignment, per-channel EQ and correct crossovers makes the same hardware sound more organised and clear. It is the same hardware producing a better result because the signal reaching each driver is correct for that driver and listening position.
Do I need to upgrade my battery for Stage 2 or Stage 3?
Not automatically. It depends on the amplifier's current draw, the charging capacity, amplifier efficiency, your riding pattern and engine speed. FLX700.4 and FLX1000.4 systems often operate on a healthy standard electrical system, but charging output and current demand still need to be checked; higher-output or multi-amplifier builds may warrant an electrical upgrade. Use the correct wiring kit for the amp and confirm the electrical picture rather than assuming. See the wiring and grounding guide.
What is the difference between an FLX PRO amp and a separate DSP?
The FLX700.4PRO and FLX1400.4PRO have a DSP built in, so you get tuning control without a separate unit, which simplifies the install. A standalone DSP (such as the HKI Mini DSP or DSP412PRO) paired with a standard amplifier lets you upgrade amp or DSP independently and can offer more output channels for complex builds. Both are Stage 3 in this framework, because both give you dedicated DSP control. For a straightforward 4-speaker system, the PRO amps are the simpler choice. See Cicada DSP Amps vs Standalone Processors.
Which stage should I start with?
If you ride mostly at low to moderate speed or are testing the waters, start with Stage 1 speakers. If you do regular highway riding and know an amp is coming, go straight to Stage 2 so you are not selecting a lower-power speaker that will not suit the amplified system. If you are building a long-term system, discuss Stage 3 with us first, because the component and amplifier choices interact.
Not sure which stage is right for your build?
Tell us your bike, how you ride, and what you are starting with, and we'll recommend the right entry point and map a path from there.
Plan My Build →Related Guides
- Do You Need an Amplifier for Harley Motorcycle Speakers?: RMS vs peak power and what headroom means at speed.
- Cicada DSP Amps vs Standalone Processors: choosing integrated vs standalone DSP for Stage 3.
- Best Speakers for a Road Glide: position-specific recommendations.
- Best Speakers for a Street Glide: fairing, saddlebag and grille tweeter options.
Motorcycle Audio Australia. Sound That Rides.