Underwater Speakers: Sound Submerged

Willem Grobler | September 19, 2023 12:52 am

We’re all used to listening to music in the above-ground world. We all know and understand that sound travels underwater as well. Even though we don’t often think about it, the reality is that nothing prevents you from listening to music underwater. The market today is flooded with waterproof Bluetooth speakers. Some will float (others will sink like a rock!), allowing you to listen to music in or around your pool. You can readily find floating pool speakers designed specifically for pools or spas.

Enter the world of underwater speakers, where sound doesn’t just travel; it immerses. The speakers mentioned above are very different from those intended to function underwater. Let’s dive into the world of underwater speakers for pools.

Clark Synthesis AQ339 Aquasonic Underwater Speakers

Best Underwater Speaker For Pools

Clark Synthesis AQ339 Aquasonic Underwater Speaker is a versatile full-range sound speaker. It is intended to be a non-permanent installation, so you can drop it into the pool and remove it at your convenience. The sound quality underwater, especially the bass, is great. This is the fastest way to add music to your pool.

electro-voice underwater speaker

Budget Option Underwater Speaker

The Electro-Voice UW30 is an omnidirectional underwater speaker with a 30W output. It is designed to be installed into the walls of your pool, making it more suitable for new pool installations. Nothing prevents you from just dropping it into the pool, though. It is supplied with a 50-foot cable.

The Science Behind Underwater Sound Transmission

Unsurprisingly, sound transmits differently underwater from in the air. Sound travels four to five times faster through water than air since water is about 800 times more dense. The wavelength of the sound for any given frequency is stretched due to this higher density. Water’s elasticity contributes to the higher transmission speeds of sound waves under water.

There are challenges associated with this phenomenon. Higher frequencies get absorbed and break down quickly, losing clarity much faster, especially over longer distances. This is the reason most marine animals use lower frequencies to communicate. There are many characteristics specific to a water mass that will further impact how sound transmits: temperature, salinity, and depth can influence the speed and direction of sound underwater. These can cause waves to change direction, slow down, speed up, or refract.

The table below summarizes how frequency ranges differ and react and how sound travels in the air vs. water. Remember, these are generalized ranges; all the above factors can influence the actual transmission efficacy.

Frequency Range (Hz)Transmission in AirTransmission Underwater
20 – 100Low frequencies can travel long distances but generally less audible to humansExcellent transmission, travels long distances and often used by marine mammals for communication
100 – 1,000Good transmission, still travels effectively, and is clearly audibleGood transmission, still travels effectively and is clearly audible
1,000 – 5,000Voice frequencies, most speech intelligibility is in this rangeReduced efficacy, attenuation (absorption) starts increasing
5,000 – 20,000High frequencies, details in music, “brightness” in soundSignificant attenuation, high frequencies don’t travel well underwater
Above 20,000Ultrasonic, generally inaudible to humansLimited transmission, used in specialized equipment like sonar

As you can see, generating and transmitting sound waves within the frequency range audible to the human ear underwater is completely possible. It becomes even more plausible when you don’t try to transmit these signals across vast bodies of water but contain them in environments as relatively small as a pool.

Sound in Water Vs Air

Some Applications of Underwater Speakers

Though the market is by no means huge, underwater speakers have found application in a few different areas and scenarios:

Recreational Swimming Pools & Spas: If you’re reading this article, chances are you’re considering adding speakers to your pool to spice up your swimming experience with music. Underwater pool speakers are becoming increasingly popular as the technologies enabling them to function meaningfully to deliver music have improved.

Professional Training: Before people started considering underwater speakers for pools at home, sports like synchronized swimming and dive training were used to enable them to train and function more effectively in those specific disciplines.

Research & Marine Communication: Scientists have been using underwater speakers and sounds for a long time in their marine life studies and communicating with divers. The actual acoustic sounds and ‘languages’ made by marine animals are where much of the knowledge regarding the underwater transfer of sounds originated. And after all this time, we are still learning!

Underwater Events: Today, it is not uncommon to see special events and performances in unique underwater settings. An annual Underwater Music Festival at Looe Key Reef, Florida Keys National Marine Sanctuary, is a good example. This unique festival features divers dressed as mermaids, sea creatures, and musicians who pretend to play instruments underwater. The music, which ranges from ocean-themed tunes to public service announcements promoting reef preservation, is broadcast through underwater speakers.

Underwater Speaker Design and Technology

Unsurprisingly, when you design a speaker to deliver sound, your first concern is waterproofing, and your second is corrosion resistance. Any speaker designed to function underwater will have to withstand the unique challenges of that environment, the first of which would be to keep water out and away from the electronic components. Advances in waterproofing have made this much easier than it used to be. Modern composite materials and plastics can survive underwater for many years. These two technologies provide the basis for all underwater speakers.

These speakers often have a higher power output to produce clear sound underwater. As discussed above, this makes up for water’s dampening effect on certain frequencies. Their diaphragms are designed to be more responsive to the medium’s density, ensuring effective sound wave production. These speakers also tend to emphasize low-frequency sounds as a workaround to this problem.

Choosing The Best Underwater Speaker for Pools

Some of the factors you need to consider when choosing an underwater pool speaker are not unlike that of any above-water speaker, but needless to say, they often have a bit of a twist. Here’s a quick checklist to consider:

Waterproof Rating

In electronic devices, the level of protection against water and dust is expressed in an internationally defined rating called an IP rating. You can read more about that rating system in our article here. Fully waterproof (IPX7-rated) speakers have almost become the norm for above-water Bluetooth speakers. Developing speakers to function for a limited time at relatively shallow depths is not hard. Manufacturer-defined IPX8 ratings will indicate that the speakers can function beyond the standard IPX7 parameters of 30 minutes underwater at no more than 1-meter depth. You must find out how the manufacturer defined IPX8, as they all may differ.

Sound Quality

You will seek a speaker that can deliver clear audio at varying depths. Unlike with above-water speakers, chances are you will not be able to listen to the speakers before making your purchase decision so you will be heavily reliant on customer reviews for individual products. Look for reviews that emphasize a balanced bass and treble sound.

Depth Rating

There is no formal “depth rating” beyond IPX7 waterproofing. Speak to the manufacturer and ensure that the speaker you purchase is powerful enough to deliver sound over your pool’s complete breadth and depth. The more water the sound needs to fill or cross, the more powerful your device will need to be.

Material and Durability

Underwater pool speakers should be manufactured from rust and corrosion-resistant materials, especially those in salinated pools. Outdoor pool speaker materials should also be UV-resistant. Examples of good speaker materials include:

  1. Stainless Steel (especially Marine-Grade, like 316L)
  2. Titanium
  3. Polymer Plastics
  4. Bronze (especially Aluminum Bronze)
  5. Neoprene Rubber (for seals and gaskets)

Power Source

Cables power most underwater speakers for pools, though some battery-powered models are starting to enter the market. If you’re building a new pool, planning for underwater speakers up-front is a good idea as it enables you to provide cabling cavities, unlike you would for a poll light. Some underwater speakers are designed to slot into the same hole as an existing pool light.

Volume Control

Volume control on an underwater speaker can often be done outside the pool. Still, the better option is to be able to daily the volume while underwater – either with a remote button or a daily on the speaker itself. It makes sense to be underwater, listening to how loud the music or sound is playing and then tuning it there, rather than going in and out of the water to try and optimize the volume levels.

Safety

Related to the power source, if your underwater speaker system is wide, then all safety precautions related to electricity and water need to be taken. Wires and cabling have to be fully and completely isolated. As per regulation, you must use low-voltage power sources to prevent eclectic hazards.

Size and Aesthetics

There aren’t many underwater speakers available, but from the range you can choose, pick a size and aesthetic that will blend with your pool. Speakers that protrude too far from the side of the pool can hurt swimmers for getting damaged when children play in the pool. Flush-mount speakers are ideal, especially those that sink into existing cavities in the pool walls.

Maintenance

You should be able to remove and install your underwater speaker easily. Regardless of how durable your set is, there will inevitably be occasions when you need to do basic maintenance or troubleshooting. Cleaning your speaker grid or removing mold from the casing should not become a complex chore.

Reviews And Brand Reputation

As mentioned before, you will very likely not be able to listen to the performance of the speakers you are interested in underwater before buying them. You must do your due diligence by reading trusted reviews and discovering the established and reputable brands in this niche-speaker space. Here are some reputable brands that manufacture underwater speakers for pools:

  1. Clark Synthesis – Known for their Aquasonic underwater speakers, frequently used in synchronized swimming and professional training environments.
  2. Lubell Labs Inc. – Renowned for producing high-quality underwater loudspeakers for various applications, including research and recreational purposes.
  3. AquaSound – They offer a variety of waterproof and underwater audio solutions, including speakers suitable for pools and spas.
  4. Oceanears – Specializes in low-cost, high-power underwater loudspeakers and surface sound sources for synchronized swimming, underwater theater, and aquatic research.
  5. Underwater Audio – While better known for their waterproof iPods and headphones, they also have experience in the underwater sound domain.

Final Thoughts

Installing a speaker in the pool may not be everyone’s cup of tea, but the good news is, if this is something you are considering, there are speakers specifically designed for this purpose. Waterproofing technologies have reached a point where you can do this safely and easily. An underwater speaker may be the ultimate party speaker.

.

Frequently Asked Questions

What are underwater speakers used for?

Underwater speakers produce sound underwater and are commonly used in recreational pools for music, synchronized swimming events, dive training, underwater film screenings, and marine research. They enhance underwater experiences by delivering clear audio below the surface.

How do underwater speakers differ from regular speakers?

Underwater speakers are specially designed to handle water’s unique acoustic properties. They are made with corrosion-resistant materials and waterproof seals and are calibrated to produce sound frequencies optimal for water transmission, ensuring clarity and longevity in submerged conditions.

Can underwater speakers be used in both freshwater and saltwater?

While many underwater speakers can be used in fresh and saltwater, it’s essential to check the manufacturer’s specifications. Saltwater is more corrosive, so speakers intended for such environments usually have enhanced corrosion resistance.

How do I maintain and clean my underwater speaker?

Regularly check for any visible damage or wear. After use, especially in saltwater, rinse the speaker with fresh water to remove salt and debris. Ensure connectors are clean and dry before charging or connecting. Store in a cool, dry place away from direct sunlight.

Do underwater speakers pose any danger to aquatic life?

Sound pollution can disturb marine life. While occasional use of underwater speakers at moderate volumes might not cause significant harm, it’s essential to be mindful. Constant loud noises or specific frequencies could interfere with marine animal communication and behavior.

Was this helpful?

Thanks for your feedback!
Share:
Photo of author

Author: Willem Grobler

Willem is an audio enthusiast who's office and home is cluttered with Bluetooth speakers and headphones. He appreciates honest speakers which delivers on their design and marketing promises. His go to speaker when traveling with his family is a JBL Flip 6, but as he loves the outdoors makes no secret of his love for the Turtlebox Gen 2.

See All His Posts