Unknown Extremely loud sound?

[MB NZ]

I know you were solo, but were there other divers from the boat? Anyone else hear it?

No, I was first in the water by about 45 minutes judging by my dive time.

 

[The Chairman]

The loudest sound I ever felt UW was being gronked by a Jewfish in the belly of a shipwreck. Ouch. I had ear problems for a week afterwards. Not what the OP described.

 

[tursiops]

The "metallic" sounds implies a lot of high-frequency content in the signal. That doesn't like propagate nearly as far as the low-frequency part of the signal. I'd guess it came from the dive boat.

 

[RyanT]

Geological seismic survey?

 

[Biotech Diver]

I think the sound was mechanical rather than biological or geological because it was so metallic in nature, but it sounded so close that I was convinced it was something going on with my first stage/tank valve. That turned out not to be the case. I wasn't too far away from the dive boat, so it could have emanated from there, but I've never heard anything like it before.

Intermitent tinnitus, maybe?

 

[lexvil]

Spear hitting you tank fired by an underwater assassin.


May as well have a fun story to tell.

 

[ontdiver]

Have you ruled out a commercial vessel? The first time a lake freighter/bulk carrier went directly over me while diving in the St Lawrence River I figured my time was up. The sound envelopes you and you have no idea where it is coming from.

 

[BoltSnap]

The sound of huge shark teeth scratching his tank when a pre-historic sized shark tried to gobble him down but couldn't after it broke its teeth and ran away.

 

[davehicks]

In Cuba I dove with some Goliath Grouper (maybe 200kg and 1.5m long) who were hunting for lobster. When they found one and chomped down on the lobster, it was incredibly loud. Like a hammer hitting an anvil loud. It would have been scary and startling if I didn't see what was happening in front of me. They must have super powerful jaws.

But I've heard dynamite fishing and that was even louder.

 

[grantmac]

Are you running environmentally sealed 1st stages and are the seals intact?