"How do I make my bike louder?" It might be the most common question we get at Mavericks Customs—and the honest answer surprises most people. The easy reply is "add more power," but that's also the wrong reply. Our friends at Cicada Audio put out a fantastic tech paper breaking down the real physics of getting loud on a motorcycle, and we wanted to put it into plain English for our riders. The short version: the speakers you choose matter far more than the size of your amplifier—and understanding why can save you a fried charging system and a pile of wasted money.
The easy answer that doesn't work
When people want more volume, the instinct is to throw a bigger amplifier at the problem. More watts, more loud, right? Not exactly. Your amplifier doesn't make sound—your speakers do. If your speakers are inefficient or can't handle the extra power, all those watts just turn into heat and distortion. Bigger power is the easy part; it's also the part most likely to lead you down an expensive dead end.
The physics of loud: the 3dB and 10dB rules
Here's the law of the land, and physics doesn't negotiate. To gain 3 decibels of output (a measurable but modest bump), you have to double your power. So going from 50 watts RMS per channel to 100 watts RMS nets you a whopping 3dB—noticeable, but not the wall of sound you pictured.
Now here's the kicker: to make a system sound twice as loud to your ears, you need roughly 10 decibels more output—and that takes ten times the power. Going from 50 watts per channel to a system that actually sounds twice as loud means jumping to around 500 watts per channel. That's not a small upgrade. That's a completely different machine.
The hidden cost: your charging system
Big power isn't just expensive at the register—it's expensive in current draw, and that's where bikes get into trouble. Every 100 watts RMS of real output pulls roughly 11.6 amps. Do the math on a serious system and the numbers get scary fast: a 500-watt-by-four amplifier pushed to full output can demand well over 200 amps of current.
Your Harley's stator might put out around 55 amps. See the problem? A stock Harley charging system was never designed to feed a monster stereo. Push it hard enough and you'll kill the battery, cook the charging system, or both. This is exactly why we always tell riders that powering a big system is its own project—one that usually means a high-output lithium battery and upgraded wiring.
But wait—music isn't a sine wave
Those worst-case current numbers come from lab tests using steady tones. Real music is dynamic—it swings from near-silence to full peaks constantly, something engineers call crest factor or dynamic range. So in the real world your average draw is much lower than the peak. That's the good news. The bad news? Those peaks are still real, and if you genuinely crank a big system, you will stress a stock charging setup. And let's be honest—nobody builds a loud stereo to keep it quiet.
The "Parking Lot Queen" trap
You've seen the builds on social media—bikes running 2,000, 3,000, even 4,000 watts RMS. Here's the part they don't show you: many of those are what the industry lovingly calls "Parking Lot Queens." They're running dual lithium batteries in the bags and often an external power supply plugged in at the show. They sound incredible… sitting still. They are not making those numbers rolling down the highway on the bike's own charging system. If your goal is a bike you actually ride that's still seriously loud, you need a smarter approach than brute force.
The smarter path: speaker sensitivity
This is the secret the pros know. Instead of buying loudness with raw watts, you buy it with speaker efficiency—measured as sensitivity (dB at 1 watt / 1 meter). A more sensitive speaker turns the same power into more volume. And on a motorcycle, where charging capacity is precious, that efficiency is everything.
Dome-style coax speakers (car-audio style)
These are the familiar coaxial speakers with a soft dome tweeter. They typically sound smooth, often have nice bass, and cost less. The trade-off is lower sensitivity—usually around 89–92dB. To make these really loud, you need a lot more power (think 4x the power for 6dB more output), which drags you right back into the current-draw problem.
Horn-style coax speakers (pro-audio style)
These use a horn-loaded compression tweeter and are built for output. Their sensitivity is dramatically higher—often 94–100dB. That means they need roughly one-quarter of the power to reach the same volume as the dome-style speakers. A quarter of the power means a quarter of the current draw—a massive advantage on a bike. They usually give up a little low-end bass and cost more (those lightweight neodymium magnets aren't cheap), but for getting loud on a motorcycle, horns win going away.
Don't forget power handling
Sensitivity gets you loud efficiently, but the speaker also has to survive being pushed. That comes down to voice coil size—bigger voice coils handle more power. It's why Cicada's CH series uses oversized coils (2" on the midbass, 1.4" on the horns): so the speakers can take the kind of abuse real bikers dish out. As they put it, if you blow their speakers, you're really working it.
What we recommend at Mavericks Customs
Pulling it all together, here's the play for a bike you ride and still want loud:
- Run high-sensitivity horn speakers all the way around—in the fairing and in the bags. They get loud on modest power and truly come alive when you add more.
- Match a medium-to-high power amplifier, like the ones in our SounDigital lineup. You won't need a monster amp to get there.
- Consider 2-ohm speakers to get more output from a smaller, more efficient amp.
- Shore up your electrical with a quality lithium battery and proper wiring if you're building big.
The bottom line
More power isn't the answer to "how do I get louder"—efficient speakers are. High-sensitivity horn drivers paired with a sensible amplifier will get you where you want to go quicker, easier, and cheaper than chasing giant wattage—without turning your bike into a parking-lot-only showpiece. Big power is great, but be smart about the battery and wiring it demands.
Hats off to Cicada Audio for the engineering breakdown that inspired this post. Want help spec'ing a system that's loud and rideable? Check out our guide to choosing bagger speakers or reach out to the Mavericks Customs crew—we ride these bikes too.