If you want to get a decent tune while out on the water, install the best audio system you can afford. This includes a marine stereo that will store and play your music, an amp to power up the signals from the stereo and good marine cables that feed a setup of about half a dozen speakers. Though each component is important in its own way, here we’ll be focusing on speakers and subwoofers.
A marine audio system differs from the one you have at home or in your car. Yes, the basics are all quite the same, but the packaging makes a whole lot of difference. Here speakers don’t go overboard in designs or shape, but are geared more towards function than form. To work in an environment where there’s constant exposure to water and sunlight, they need to be built tough, while also providing some substance.
What to Look for in Marine Speakers?
Speakers for boat audio systems are either waterproof or water-resistant, with different Ingress Protection or IP ratings. They need to stand up to water spray and the corrosive effect of sea salt. And since most will be installed along open decks, humidity or fog can also ruin speaker drivers, as can the prolonged exposure to the sun’s UV light. Outer casings and baskets are therefore made of UV-resistant plastics with rubber surround to wick off any incoming water or spray. Inside, speaker cones (the parts that vibrate and produce sounds) are made of durable polypropylene and the high-pitched notes come from mylar tweeters. The cones vibrate when pushed from corrosion-resistant ferrite magnets housed in sealed water guards. All this is connected by cables with PVC sheathing and additional internal insulation.
So, yes, quite a bit different from the exposed copper cables, polished wood trims and paper or composite cones and tweeters snuck tight in metal frames of your speakers in your home hi-fi. Of course, here you don’t have water constantly splashing around.
To hear anything amid the rumble of waves and the onboard engines, boat speakers need to have the appropriate output. This is measured in watts, the bigger the number the louder the speaker. Look for high RMS wattage or the continuous power a speaker can handle. Decent speakers start at 50W RMS, with peaks of 100W, whereas high-end speakers for boat average around 100W RMS, with peaks of 200W. Subwoofers for louder and deeper base can handle 200W RMS and peaks of 400W. A common setup is 4 speakers and a subwoofer.
Pairing speakers to the right amplifier also makes a difference in sound. A 5-channel amplifier is required to run the setup described above. For 100W speakers, an amp with a total of 500 W can run 75W per channel and 200W for the subwoofer. A little maths, but necessary so you don’t blow the speakers. Most amps are digital, meaning they can adjust the sensitivity according to that of the speaker. This is impedance, measured in Ohms, the lower the number (usually 4Ω in most marine speakers) the easier they are driven by the amp.
The sound quality in speakers for boat audio largely depends on the number of individual speakers within each casing. There are three basics types:
- Dual cone speakers – These are simple designs consisting of two cones, one for the midrange tones, and another smaller cone for the higher-pitched sounds directly attached over the larger cone. They are fed only by a single wire, so sound can be muddled.
- Coaxial speakers – or two-way speakers consist of a separate tweeter and midrange woofer. Like the dual cone design, the tweeter is set in the middle of the larger cone. The different frequencies are fed through two separate wires, meaning better sound separation making them the most popular choice in marine audio.
- Component speakers consist of detached woofers and tweeters meaning less distortion. Each unit is separately run by the amp, so no meddling of sounds. This is the most expensive speaker setup, but with the clearest sound.
- Subwoofers – Subwoofers handle the bass, have higher power ratings, and are paired with several coaxial or component speakers for the best sound. You’ll need a separate amp to drive it, so factor in the cost.
Speaker Placement and Installation
Speakers are either flush-mounted into the side walls along the deck or placed higher up. Consider the size of the flush mount speaker, both in terms of overall diameter including outer seals and the depth of the speaker. These need to align with the rest of the boat surfaces for the best sound. Also, there needs to be minimal air space behind the speaker, so you get fuller, more defined music. If you don’t have adequate space for flush-mount speakers, then go for box mounts, which are usually installed higher up. Where you place the speakers is also important for the soundstage. You should hear equal volumes and definitions in different areas in the boat. Ideally, place the subwoofer in an enclosed area, like under seats, in the centre.
Pair your equipment at equal price points. No use in having an expensive amp running cheap speakers, or the other way round. For installation, speaker types, equipment pairing and output consult your nearest store selling quality marine audio equipment.