Powerful underwater speaker

[LEO1982]

This is a good idea! But we need the director to direct the people in the water more often.

 

[OMyMyOHellYes]

Please keep your music out of the tranquil water.

 

[Sure Squintsalot]

Wasn't there some acoustics-based system that had come out recently to be used as the basis for divers being to locate each other? sounded like the perfect system for a DM to keep track of his/her group.

What ever happened to that?

 

[OMyMyOHellYes]

Wasn't there some acoustics-based system that had come out recently to be used as the basis for divers being to locate each other? sounded like the perfect system for a DM to keep track of his/her group.

What ever happened to that?

Useless concept.

Sound travels so fast in water that it is, in all practical terms, impossible to tell directionality or distance based on stereo differential.

 

[Sascha314]

I like diving also because I can enjoy the silence and no disturbtion or someone just talking and talking or some loud music I do not like.

So that would be a reason to never dive there.

 

[34109411]

For many years, we have been using a homemade underwater loudspeaker at our base to entertain and notify divers. We simply put a powerful speaker in a pressure cooker, installed ip68 cable gland in the lid and connected the wire to an amplifier on the shore. The pressure cooker is at a depth of 5 meters, the speaker power is 50 RMS, the amplifier power is 25 RMS. The speaker was loudly audible underwater at a distance of 30-50 meters, weakly audible at a distance of up to 100 meters.
This year, we replaced this speaker with a 50-watt vibration speaker and received an incredible increase in volume. Now music or our voice commands can be clearly and loudly heard at a distance of 450 meters on the opposite shore.
I do not propose to pollute all the seas and lakes with loud sounds, but I want to share an economical technical solution that competes in efficiency with expensive specialized systems and it can be useful for various purposes.
For example, in our case, we transmit voice commands during underwater sports events, repair work, etc. Also, some experienced divers quite accurately indicate the direction of the sound source and use it for underwater navigation.

mmm world of silence... to entertain and notify diver ?? Use it for underwater navigation???

You should consider to add a big screen tv to entertain people at safety stop or if they get bored. So like this you will have à underwater home theatre.

If i be a dolphin swimming around i will say what the f... is going on around here.

oh i am speechless i don't wont to debate that one.

 

[34109411]

Good morning, we do not transmit alert tones, but simply speak into the microphone and the divers clearly hear the commands even when exhaling. We also turn on music and the sound quality is very good, without wheezing and distortion. So I am sure that any sound tones will also be reproduced very loudly and with high quality.
As for the cost of all the parts:
A wide-range vibration speaker from Aliexpress costs about 75 euros (depending on delivery).

80W-15W Full Range Vibration Lautsprecher Anti-neighbor Audio Tragbare Lautsprecher Vibro Resonanz Bass Sound Erreger subwoofer - AliExpress 44

Smarter Shopping, Better Living! Aliexpress.com

de.aliexpress.com

As an amplifier, we use a powerful car radio with a nominal power of 25 watts according to the specification (the measured average maximum is about 80 watts), we do not turn it on at full power, I think about 50 watts. And although the vibration speaker heats up to about 50 degrees, it has been working great for more than six months. The radio was bought a long time ago and I don't remember the price.
The only direct costs left are the pressure cooker and thick wire. We bought the pressure cooker at a sale for $30, and took a regular cable for electrical wiring.
If I were you, I would buy only a vibration speaker and test the result with any pressure cooker and an available amplifier before buying anything specifically for this project. The speaker is simply glued to the pressure cooker with hot glue and even if you don't like the first pressure cooker you come across, it will remain undamaged.

Good morning, we do not transmit alert tones, but simply speak into the microphone and the divers clearly hear the commands even when exhaling

man you make my day ok diver at 20 feet you are at 500 psi time to go up !

 

[Waterwulf]

I'd be upset about it if it happened near me. I go underwater to get away from crap like that. I also do a lot of offroading with my Rat Rod Trail Rail. Nothing like cruising along a neat old mining trail and have some jerk in a SXS come along the same trail but he has his sound system blasting as loud as it will go. AAARRRGGGHHH!!! Turn that crap off.

 

[Sure Squintsalot]

Useless concept.

Sound travels so fast in water that it is, in all practical terms, impossible to tell directionality or distance based on stereo differential.

Good thing you don't work in the patent office.

Acoustic based underwater positioning systems are a thing, and, apparently industry proven. From Subaboard's own pages:

Presenting RedWAVE, a ready and available underwater GPS system​

We took the functioning of satellite navigation systems as a basic principle, but instead of satellites, four small RedBASE buoys on the surface of the water retransmit the satellite signal underwater in the form of acoustic waves. This type of navigation system is called a long base-line, or LBL.

From other places where determining "directionality or distance based stereo differential" using acoustics wasn't a useless concept:

Acoustic navigational tech gets scuba divers using GPS maps​

Because GPS doesn't work underwater, divers usually can't track their real-time position on a digital map. The new Diver Navigation System (DNS) gets around that problem, however, using both floating and wearable acoustic transponders.

Ocean Plan

Ocean Plan brings together many skilled scientists with exceptional R&D experience in the field of underwater communication and underwater positioning, uses advanced underwater acoustic science and technology to creatively apply underwater positioning, underwater navigation, and underwater communication technologies together and develop Underwater Communication and Navigation System 400D, 1500D series.

Navygator-T is a miniature DiverTrack system. After connected with host device Navygator-Pro or Commander-10, the host device can grasp Navygator-T's underwater location and diving activity status in real time, that means Navygator-T is passively tracked device when underwater; Navygator-T can send SOS alarm signal to other divers or boat stuff to get immediately support.

 

[Sascha314]

The human cannot differentiate the direction as he is "used" to the speed of sound in air and thats how the ear distance is "built".

With very quick sensors you can of course achieve otherwise ... but yeah I want to enjoy the silence.