BrendanS
Well-Known Member
Re: Ah but Brendan and Brett H...
Apologies, but the git was asking for it! Ooops!
Apologies, but the git was asking for it! Ooops!
'Snap crakle and Pop' noise from under hull?
- Thread starter Anthony
- Start date
Freebee
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
I can also claim to have heard this type of noise, it was 1965 I was a teenager and on holiday with my folks on the Norfolk broads moored at Salhouse broad in a hire boat made of ferrocement. On Salhouse broad you moored by boshing the bow up the bank.
Any way in the middle of the night we were treated to the snap crackle pop noise, my dad tried everything he knew how to see if anything on the boat was causing it. This included a vicious pumping session on the sea toilet, running taps and eventually cutting through the gas line on the gas bottle and dumping it over the side, still the noise continued-the story of my fathers frantic attempts to find the source has long since passed into family folklore. we came to no conclusion and to this day I cant explain it.
I can also claim to have heard this type of noise, it was 1965 I was a teenager and on holiday with my folks on the Norfolk broads moored at Salhouse broad in a hire boat made of ferrocement. On Salhouse broad you moored by boshing the bow up the bank.
Any way in the middle of the night we were treated to the snap crackle pop noise, my dad tried everything he knew how to see if anything on the boat was causing it. This included a vicious pumping session on the sea toilet, running taps and eventually cutting through the gas line on the gas bottle and dumping it over the side, still the noise continued-the story of my fathers frantic attempts to find the source has long since passed into family folklore. we came to no conclusion and to this day I cant explain it.
paulburton44
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
I thought it was the fibreglass/ metal work contracting / expanding after a day in the hot sun...???
I thought it was the fibreglass/ metal work contracting / expanding after a day in the hot sun...???
tcm
...
Re: \'Snap crakle and Pop\' noise from under hull?
again, that must be a different noise. The snap crackle pop in question is most audible from inside the bilges with engines off in calm or calmish anchorage or in marina. You could hear it over the engines and it is constant - at least as constant as ciccadas in the med frexample, endlessly going on and on and on, continuoully without stopping er i think that explains "constant" fairly fully, ahem.
There could be a noise from differential expansion/contraction but that would be a one-off-ish noise, not constant. Outside the house frinstance when the sun comes from behing a cloud and if your house has got newish but cheapish contract guttering it will all creak. But once expanded, that's it, it has taken a new position. It doesn't chunter along endlessly cos it's warm. Ok, it might creak if your guttering is not that cheap too. But if it was ded expensive it would be nice zinc stuff that lasts a zilion years like in france and germany with all proper joint so no plasticky snap-on joints. Hopefully we don't need to discuss guttering too much.
again, that must be a different noise. The snap crackle pop in question is most audible from inside the bilges with engines off in calm or calmish anchorage or in marina. You could hear it over the engines and it is constant - at least as constant as ciccadas in the med frexample, endlessly going on and on and on, continuoully without stopping er i think that explains "constant" fairly fully, ahem.
There could be a noise from differential expansion/contraction but that would be a one-off-ish noise, not constant. Outside the house frinstance when the sun comes from behing a cloud and if your house has got newish but cheapish contract guttering it will all creak. But once expanded, that's it, it has taken a new position. It doesn't chunter along endlessly cos it's warm. Ok, it might creak if your guttering is not that cheap too. But if it was ded expensive it would be nice zinc stuff that lasts a zilion years like in france and germany with all proper joint so no plasticky snap-on joints. Hopefully we don't need to discuss guttering too much.
paulburton44
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
guttering ????? thought we were talking boats ?????
guttering ????? thought we were talking boats ?????
tcm
...
Re: \'Snap crakle and Pop\' noise from under hull?
i was just using guttering as an example of how things expand and contract. Anyway, i've got guttering on my boat (a bit) so no need to jump out of the tree just yet - stay up here with the rest of us!
i was just using guttering as an example of how things expand and contract. Anyway, i've got guttering on my boat (a bit) so no need to jump out of the tree just yet - stay up here with the rest of us!
Trevor_swfyc
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
Clearly its not prop noise as the noise would come and go, no it is continuous and tends to be of constant volume. In greece the noise of the crickets during the day is very similar, in that it is constant when you are within earshot of land. I would suspect the water born noise is a creature and that they are doing the same thing, trying to attract attention maybe to propagate and from the sound of it they are as successful as the crickets.
Could the sound be a clue in that it sounds like electric discharge, maybe its fish settling their potential differences. /forums/images/graemlins/wink.gif
Trevor
Clearly its not prop noise as the noise would come and go, no it is continuous and tends to be of constant volume. In greece the noise of the crickets during the day is very similar, in that it is constant when you are within earshot of land. I would suspect the water born noise is a creature and that they are doing the same thing, trying to attract attention maybe to propagate and from the sound of it they are as successful as the crickets.
Could the sound be a clue in that it sounds like electric discharge, maybe its fish settling their potential differences. /forums/images/graemlins/wink.gif
Trevor
alahol2
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
I've only ever heard it in one place, northern end of Portland harbour. I've heard it several times over the years and long ago came to the conclusion that it was shrimps (or some other crustaceans) either eating or 'chatting' about the days happenings.
I've only ever heard it in one place, northern end of Portland harbour. I've heard it several times over the years and long ago came to the conclusion that it was shrimps (or some other crustaceans) either eating or 'chatting' about the days happenings.
tcm
...
anthropomorphised shrimps
Hm - if they were just chatting wouldn't there be some guffaws and raised voices? I don't suppse there are too many jokes made by shrimps really, though, so maybe not. Perhaps it's more like the noise made by loads of people in very large and free underwater restaurant, do you think? Perhaps clinking a glass would make them pipe down a bit at night.
Hm - if they were just chatting wouldn't there be some guffaws and raised voices? I don't suppse there are too many jokes made by shrimps really, though, so maybe not. Perhaps it's more like the noise made by loads of people in very large and free underwater restaurant, do you think? Perhaps clinking a glass would make them pipe down a bit at night.
whisper
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
The only time I've heard it was about 15 yrs ago in Lulworth Cove during my Day Skipper Practical. After much wondering about the scource we detected lights under the water. Three scuba divers were swimming about amongst the anchored yachts - we therefore assumed it was them, eating crisps as they went along /forums/images/graemlins/confused.gif.
The only time I've heard it was about 15 yrs ago in Lulworth Cove during my Day Skipper Practical. After much wondering about the scource we detected lights under the water. Three scuba divers were swimming about amongst the anchored yachts - we therefore assumed it was them, eating crisps as they went along /forums/images/graemlins/confused.gif.
Courageous
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
Sorry to poop on your rice krispies but this is a common phenomena here in the med and as with most of these things you can't do much wrong if you at least ASK the locals what you are experiencing. I was swiftly informed that the noises are caused by fish the spanish refer to as castanetes (presumably after castanetts). They aren't feeding off the hull of my boat as it was the first night in the pond after fresh scrub and antifoul........ Prop noise indeed - whilst NOT the most gallant of repostes I have to agree with BrendanS as to the ridiculous nature of the continued response..... Have noticed some people DO claim to be expert in all things on this forum and do not always have the credentials to support it (Particular thanx go to the clown who advised me to scrub my stainless pushpit with a stainless dish scrubber - it's as dull as mild steel now thanx!!!) /forums/images/graemlins/grin.gif
Sorry to poop on your rice krispies but this is a common phenomena here in the med and as with most of these things you can't do much wrong if you at least ASK the locals what you are experiencing. I was swiftly informed that the noises are caused by fish the spanish refer to as castanetes (presumably after castanetts). They aren't feeding off the hull of my boat as it was the first night in the pond after fresh scrub and antifoul........ Prop noise indeed - whilst NOT the most gallant of repostes I have to agree with BrendanS as to the ridiculous nature of the continued response..... Have noticed some people DO claim to be expert in all things on this forum and do not always have the credentials to support it (Particular thanx go to the clown who advised me to scrub my stainless pushpit with a stainless dish scrubber - it's as dull as mild steel now thanx!!!) /forums/images/graemlins/grin.gif
BrendanS
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
Oh OK, I wasn't feeling very 'gallant' at the time! Response still stands though
Oh OK, I wasn't feeling very 'gallant' at the time! Response still stands though
ShipsWoofy
Well-Known Member
Re: \'Snap crackle and Pop\' noise from under hull?
how loud is this noise, the sound Brendan posted sounded like a well established bonfire, and quite obviously I could change the volume.
Is it background, where you have to shut everything off to hear it and stay really still with shallow breathing. Or, is it overwhelming like Chinese torture where you would rather stick knitting needles down your lug holes than listen to another second of that damn racket.......
how loud is this noise, the sound Brendan posted sounded like a well established bonfire, and quite obviously I could change the volume.
Is it background, where you have to shut everything off to hear it and stay really still with shallow breathing. Or, is it overwhelming like Chinese torture where you would rather stick knitting needles down your lug holes than listen to another second of that damn racket.......
BrendanS
Well-Known Member
Re: \'Snap crackle and Pop\' noise from under hull?
Knitting needles, without the sound control.
Think we can get this thread to over 100 despite the innocuous start?
Knitting needles, without the sound control.
Think we can get this thread to over 100 despite the innocuous start?
TheBoatman
Well-Known Member
For what its worth!
Whilst on hols in the Med we had exactly the same noise, it was so bad that we thought there was an electrical fault and something was arcing out. All investigations revealed nowt. When I mentioned it to a local he said [ QUOTE ]
"its small freshwater springs discharging near the boat and it makes a crackling sound"
I didn't believe him for one minute until I dived down and tried to find the source, when I did there was a small water jet bubbling out of the rocks making a crackling sound.
So there you have the answer,,, its freshwater discharging into saltwater.
Next time you hear it get the snorkle out and have a look.
Peter. /forums/images/graemlins/smile.gif
Whilst on hols in the Med we had exactly the same noise, it was so bad that we thought there was an electrical fault and something was arcing out. All investigations revealed nowt. When I mentioned it to a local he said [ QUOTE ]
"its small freshwater springs discharging near the boat and it makes a crackling sound"
I didn't believe him for one minute until I dived down and tried to find the source, when I did there was a small water jet bubbling out of the rocks making a crackling sound.
So there you have the answer,,, its freshwater discharging into saltwater.
Next time you hear it get the snorkle out and have a look.
Peter. /forums/images/graemlins/smile.gif
Ships_Cat
Well-Known Member
Re: \'Snap crackle and Pop\' noise from under hull?
We get it here in NZ in some locations (and that prompted the earlier thread on the same thing), just as Brendan's audio link and as described. Is definitely not propeller noise cos you get it in some places and not others regardless of boat traffic far or close. Perhaps it could be argued that location specific means that the water is somehow different in each place and that makes it not heard in some places but heard in others, but I suggest anyone going down that track would likely prompt a few guffaws.
Is claimed to be shrimp here in NZ and seems to be likely as a port we regularly visit and the noise is often very strong, does seem to have a very happy and large population of shrimps. But some may also be due to small fishes sucking the bottom, at least in our case in that our bottom is both often dirty and only 4 mm thick - so lots of little fishies sucking its bottom.
John
We get it here in NZ in some locations (and that prompted the earlier thread on the same thing), just as Brendan's audio link and as described. Is definitely not propeller noise cos you get it in some places and not others regardless of boat traffic far or close. Perhaps it could be argued that location specific means that the water is somehow different in each place and that makes it not heard in some places but heard in others, but I suggest anyone going down that track would likely prompt a few guffaws.
Is claimed to be shrimp here in NZ and seems to be likely as a port we regularly visit and the noise is often very strong, does seem to have a very happy and large population of shrimps. But some may also be due to small fishes sucking the bottom, at least in our case in that our bottom is both often dirty and only 4 mm thick - so lots of little fishies sucking its bottom.
John
MASH
N/A
Re: \'Snap crakle and Pop\' noise from under hull?
Dear Mr (Captain) Courageous posing in your left hand seat, it ain't no fish! How could a fish all made of jelly and soft stuff make such a mechanical noise? No Sir! It's crustacea clicking their legs on their shells or something, just like grasshoppers do. But grasshoppers do it on land and these fellas do it underwater...see?
Its shrimps. Bloody shrimps I tell you!!! Aint no fish in my part of the Med anyway, all been hoiked out for tourists like me to scoff...fried with fennel and garlic and lemon juice and hf hf hf fhthrmm slurp omigod I'm hungry!
point is, it is just as loud in the marina as in the open bays and there are
virtually none of the small fish in the marina that you do see iin the bays. Marina is, however, full of crustacea.
Couldn't be the glass fibres snapping as a result of overstress from a granite intrusion, could it Courageous? /forums/images/graemlins/wink.gif
Heads down! Incoming!
ps. Solvol Autosol and a bit of rag will sort out your SS problems. Sorry to hear the Good Ship is not at her shiniest at present...What the hell do you liveaboards do all day? Work or something??
Dear Mr (Captain) Courageous posing in your left hand seat, it ain't no fish! How could a fish all made of jelly and soft stuff make such a mechanical noise? No Sir! It's crustacea clicking their legs on their shells or something, just like grasshoppers do. But grasshoppers do it on land and these fellas do it underwater...see?
Its shrimps. Bloody shrimps I tell you!!! Aint no fish in my part of the Med anyway, all been hoiked out for tourists like me to scoff...fried with fennel and garlic and lemon juice and hf hf hf fhthrmm slurp omigod I'm hungry!
point is, it is just as loud in the marina as in the open bays and there are
virtually none of the small fish in the marina that you do see iin the bays. Marina is, however, full of crustacea.
Couldn't be the glass fibres snapping as a result of overstress from a granite intrusion, could it Courageous? /forums/images/graemlins/wink.gif
Heads down! Incoming!
ps. Solvol Autosol and a bit of rag will sort out your SS problems. Sorry to hear the Good Ship is not at her shiniest at present...What the hell do you liveaboards do all day? Work or something??
oldharry
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
Frustrated and hungry gribble, teredo etc trying desparately to find their next meal....?
Frustrated and hungry gribble, teredo etc trying desparately to find their next meal....?
bbg
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
I also think that the critters that are making the noise are not necessarily on the hull, for several reasons. First, I have never seen creatures feeding on the slime on the hull when I have been snorkelling, although I haven't specifically looked. Next, you can hear the same sound if you go snorkelling - even quite far away from other boats - and I have never noticed creatures feeding on the slime inside my ear (although I haven't specifically looked). Next, the link that BrendanS gave us is from a hydrophone, which picks up sounds in the water, not sounds from creatures that are feeding on the hydrophone itself. Finally, I have heard this sound as soon as we turn the engine off after anchoring, which wouldn't give much time for the creatures to find their way to the boat. And I have never heard the sound gradually grow in intensity / volume which would indicate that more and more shrimps are sitting down (on the hull) for dinner.
BrendanS - when you look back at BrettH's original post, do you really think he was "asking for it"? Did it really justify your response? It looks to me like he was giving an explanation for a sound he has heard. Many of us have heard a different sound which has a different explanation, but I don't see his original post as anything other than his view on it.
I also think that the critters that are making the noise are not necessarily on the hull, for several reasons. First, I have never seen creatures feeding on the slime on the hull when I have been snorkelling, although I haven't specifically looked. Next, you can hear the same sound if you go snorkelling - even quite far away from other boats - and I have never noticed creatures feeding on the slime inside my ear (although I haven't specifically looked). Next, the link that BrendanS gave us is from a hydrophone, which picks up sounds in the water, not sounds from creatures that are feeding on the hydrophone itself. Finally, I have heard this sound as soon as we turn the engine off after anchoring, which wouldn't give much time for the creatures to find their way to the boat. And I have never heard the sound gradually grow in intensity / volume which would indicate that more and more shrimps are sitting down (on the hull) for dinner.
BrendanS - when you look back at BrettH's original post, do you really think he was "asking for it"? Did it really justify your response? It looks to me like he was giving an explanation for a sound he has heard. Many of us have heard a different sound which has a different explanation, but I don't see his original post as anything other than his view on it.
BrendanS
Well-Known Member
Re: \'Snap crakle and Pop\' noise from under hull?
They are not on the hull, they are in the water like normal.
Think it's time for some IQ tests around here.
They are not on the hull, they are in the water like normal.
Think it's time for some IQ tests around here.