More sonar engine sounds?

[wdq4587]

There are 2 kind sound: engine sound and propeller sound. If someone can got sound recording from modern submarine hydrophone, that will be easy. And if SH3 allow extend number of engine type, that will be not difficult to add it.

[geosub1978]

Guys, guys, guys!

What the sonarman hears by the hydrophone is NOT the engine sound. This is impossible! Only modern LOFAR procedures can create a frequency pattern of an engine, but certainly NOT an acoustic effect. The only case is if you are 10 meters UNDER the target or something like that!

What a sonarman listens are:

1st: Flow noise. This is the passing of the hull through the water. This has to do with the shape-speed-clariy of the hull-waves. This coases the initial contact and usually warships have a more clear hull and they are more slimm lined (cruisers-destroyers) and they are distincted. I don't know about battleships......

2nd: Propeller sound. This can be distinctive form great distances but maybe not as well. This has to do with the number of propellers, the shape/size and the RPM. The sonarmen should be able to distinct a merchant from a warship by the propeller sound. Counting the beats of the propeller and knowing the TPK could determine the speed or reverse. They determined the speed by plotting, the sonarman counted the beats and thus prodused the TPK for that specific class of target and could use it for future speed calculations when they met that class of target again!

I doupt that any sonarman ever heard engine sound itself!

What should have been done in SH3 which is realistik is the distinction of fishimg boats and the rest junk! The sonarman should be able to identify a fishing boat and prevent you from spending 2 hours approaching just to realise that this is a fishing boat!

So I think a more reasonable classification would be:

1. Merchant Big
2. Merchant Small
3. Warship Big
4. Warship Small
5. Fishing boat/trawler

Based on what geosub says, my reasoning tells me that the hull on a battleship is much wider and flatter than that of a frigate. Also, it'll have bigger and possibly more props (not got time to load the museum atm cos i work nights at the weekends).
Both instances tell me the sound of the above 2 ships will be markedly different.

I agree completely with your fishing boat comments.

I wonder though, if the sonar won't pick up the mechanical noise of the engines if it's capable of picking up the tap of a metal object on a hull?

The engines in these ships are BIG diesels, in metal hulls.

I have to admit i've never heard the RL feedback from sonar, and from a submarines perspective in my life, so i'll have to leave that debate to better informed people.

I do drive articulated lorries for a living tho, and they don't all sound the same.
Water transmits sound and vibration further than air or solid ground i believe?

So . .IF . . mechanical noise can be distinguished an experienced sonar operator may even be able to distinguish between a WW1 era merchant/cargo and a WW2 one, if the older one sounds coarser or has more rattles lol.

The prop and hull configurations alone suggest to me there would be more variation in the hydro sounds than exist in SH3 currently.
It wouldn't surprise me if the sounds were done like so many things in stock SH3, as a rush job in order to meet a deadline. So what we have is the most basic set of hydro sounds, that can be improved upon.
Even so, based on what they've included in stock we already have different sounds for Tankers compared to merchant/cargos.
Destroyers and frigates.
Battleships and carriers ( the carrier has a kind of rattle in the sound, and i think a slightly more meshy sound, distinguishing it from a battleship).
Plus there's the passenger ship hydro, of similar size, hull dimensions, prop numbers and performance to the BB's and AC's, yet different.

Large merchant/cargos and smaller ones.

Excepting the latter group, each group is mostly of similar size, hull dimensions and performance to each other, yet they have different sounds.


Sailor Steve i wasn't thinking of quite that much individuality m8

I've never heard a story in which a soundman says "Captain, that's an American C-3!"

Just more than exists at present


And thanks again Task Force, i hope you're right.

Specially since PT's good with sound files

[geosub1978]

Originally Posted by roadhogg

I wonder though, if the sonar won't pick up the mechanical noise of the engines if it's capable of picking up the tap of a metal object on a hull?

The engines in these ships are BIG diesels, in metal hulls.

1. It is exactly as above water. Have you ever heard the engine of a ship underway when you are on the deck of a liner (if you have travelled with a ship f course)? Ceratinly NOT! You can only hear the passing of ship through the water. Only in small/very small ships you can hear the engine! The same happens underwater but because of the greater density of water mass the sound travels at greater distances!

2. NOOOO! At 50% of the merchants the engines are old styled steam cylinder engines (triple exhaustion/expantion or something like that). At 20% of the merchants the engines are diesels (motorships) and at 30% are steam turbines. As for warships: At 95% their engine is steam turbine, at 4% diesels (e.g. GRAF SPEE), at 1% old style steam cylinder (WW1 era e.g. AVEROF)

3. The capability of a sonarman to distinguish something is a matter of skill/knowledge/experience/sound propagation.

4. In the game the individual sounds can made very distinguishing of course, but again the report will remain the same "WARSHIP" or "MERCHANT" as it is once again hardcoded matter...You have to identify it by yourself!

[Philipp_Thomsen]

Roadhogg, mind beta-testing some new hydrophone sounds for the sound pack V4 for me?

[wdq4587]

Really interesting. It seems SH3 hydrophone sound: ship sound and ping sound are all wrong.

When I first time play SH3. I wonder why ship sound are different compare to Danger Water's sound. I can here the engine sound. And then I guess may be that old style steam cylinder engine sound are much loudder and the ship hull are works like a speaker. Now I know that's not true.

1) I don't think i've ever been on anything bigger than the Woolwich Ferry

Must fix that one day and book myself a cruise on a big liner.

2) The different sound files of the tankers compared to merchants may be partly due to them being wider than the cargo's and merchants then, therefore displacing water at a wider angle - flow noise. And possibly different prop sizes/numbers.

By the same token a 10,000 ton ship should create a different flow noise to a 5,000 ton ship due to the width and length of hull , number/size of props etc.

3) which would result in benefits to the game players in building up experience at the sonar station to differentiate between the different hydro sounds, IF there were more subtle variations in the sounds.

4) If the reports stayed the same, see 3) above .
Saves the game doing the work for you. If you don't wanna waste your time chasing useless contacts, get on the sonar yourself.


Yes PT, i'd be happy to.

Had a look on your "version 3.2" thread and noticed the comment for V4 says " New multiple hydrophone engine sounds". Seems you're on the case already. Thanks dude

Couldn't find the download of V4 on your filefront page tho.

You mean the hydro sounds in SH3 differ from those in Dangerous waters wdg4587?

Are the hydro sounds in Dangerous Waters realistic?

And how do you know the hull doesn't work like a speaker and the steam cylinder engines are not much louder, on the basis of what geosub has said?

Engines create vibration, vibration creates sound, and given the size of the engines used in ships, and the effectiveness of water as a sound conductor....

No disrespect intended to geosub, and he obviously knows more about the dynamics of sonar than i do, but his comments suggest to me that to an extent, even he is guessing.
Or is he?
Certainly geosub has been ON a ship, but has he ever been UNDER one?

Has anyone actually heard the sonar sound of different ships received by a sub?

Anyone that has please step forward. And i mean that most sincerely

[geosub1978]

Originally Posted by roadhogg

You mean the hydro sounds in SH3 differ from those in Dangerous waters wdg4587?

Are the hydro sounds in Dangerous Waters realistic?

And how do you know the hull doesn't work like a speaker and the steam cylinder engines are not much louder, on the basis of what geosub has said?

Engines create vibration, vibration creates sound, and given the size of the engines used in ships, and the effectiveness of water as a sound conductor....

No disrespect intended to geosub, and he obviously knows more about the dynamics of sonar than i do, but his comments suggest to me that to an extent, even he is guessing.
Or is he?
Certainly geosub has been ON a ship, but has he ever been UNDER one?

Has anyone actually heard the sonar sound of different ships received by a sub?

Anyone that has please step forward. And i mean that most sincerely

I know what I am saying! And believe me I have been below another ship. Thank God it wasn't just 10meters:rotfl: .

As for the flow noise, there is a level of distinction like that:

Warship/Merchant/Well maintained/new merchant/motorship/fishing boat.

Don't take for granted that because the flow noise of a 5000tn ship is diffrent that a 10000tn ship this will lead the sonarman to determine the displacment! He will identify a MERCHANT!

[wdq4587]

Originally Posted by roadhogg

You mean the hydro sounds in SH3 differ from those in Dangerous waters wdg4587?
Are the hydro sounds in Dangerous Waters realistic?

In game Dangerous Waters you most time are hearing hydrophone sound and of course looking at sonar screen. And there are less graphics you can see and even no one picture of submarine interior. And I guess these guys also develop simulator for Navy.

Were you in a submarine when you were below this ship wdg?

If so did you hear any engine noise?

And hello btw

All i'm trying to find out here, is whether engine noise can be detected through sonar, and how much the flow noise differs between different sizes of ship.

The fact that the prop noise is discernable enough for a WW2 sonar operator to be able to count the prop revs is already known.

I'm not suggesting the flow noise difference between a 5,000 ton ship will be discernable from the flow noise of a 10,000 ton ship, but the flow noise isn't the only sound detected by sonar, and the sonar noise picked up between a small and large merchant may be different. ie: 2,500 and 10,000 tons.
If not from the flow noise, then the sound of the props. Or maybe the sound of the engines, or all three elements combined.

I've looked in the sound files of SH3, and the engine noise is included in some of the files. In others, strangely, it seems to be absent. Some of the files appear to be mis-named accordin to the sounds within them.

I'm just trying to determine what can reasonably be expected to be picked up by sonar, and how the noise differs when tracking various ships using it.

Until we can establish just how much, or what differences cause sonar to detect a noticeably different sound from one ship versus another, we're all going round in circles with different ideas and opinions, and no one can agree on any improvements.

If the developers of Dangerous Waters make simulators for the Navy, but it doesn't allow the ability to determine a ships speed from the prop rotation, then they can't call it an accurate simulator, since we know that can be done. Therefore theres still room for improvement.

[geosub1978]

When a ship passes over you, you can only hear the propeller revolution, nothing else! Sometimes if the target is fast the submarine shakes a little bit. Not an engine sound you can forget about that!

As for the rest that you say, I think you state it correctly, but in order to catch up all these you need much imagination because there is not much experience on something like that. I can say you for example:

1.The warship's propeller beating is more sharp, and the flow noise also sharp, because the surfaces of warhip's hull are more frequently cleaned that the merchants.

2. A fishing boat usually has a two stoke engine and a very fast rotating shaft (difficult to count beats) and generally it sounds like "tttrrrrrrrrrrrr"

I feel like i've written loads on a question that had a straightforward answer, if the answer came from someone that knew what sonar from a sub sounds like when listening to ships.

Interesting that the flow noise of a warship can be differentiated from a merchant simply because the hull is cleaned more often

Any idea why the prop sound is sharper?

As for the rest of what i said, the basic sounds already exist, and as you say, i think all that's needed is some imagination. For example, the flow noise can be altered slightly, say made to sound a little deeper or sharper, for wider hulled and bigger ships, and ships with bigger props would do less revs for their given speed than smaller ships, and sound sharper and/or deeper too. The type of noise would also depend on how many props the ships had.

The effects between ships can be scaled, say with almost indescernable differences for similar sized/width ships in prop and /or flow noise, but more noticeable when tracking ships of increasing difference to each other.

If it's done right you wouldn't be able to tell some apart, but others you would, and it would depend on how "tuned in" your hearing was, and of course experience.

Apologies if i had doubts about the accuracy of your earlier comments, it wasn't clear to me what kind of experience you spoke from, or whether it was guesswork.

You might have been a diver or something and heard a ship pass overhead.

Your last post cleared that up. You've been under a ship in a sub and listened to it.
That's the kind of input i was looking for if possible, from someone that knew first hand what he was talkng about.

Thank you geosub

[geosub1978]

It is not only the hull that it usually clearer, it is also the smoother hydronamic line of the warships that makes the diffrence in flow noise. I don't know about battleships and carriers.

The propellers are also distinguished, for the same reason. They should be clearer and designed to meet other requirements.

Another distinguishing characteristic of the old merchants is a noise produced by the shaft, which by the years, tends to "drop".

But I don't dare to tell you more because I am not a sonar specialist.

IS THERE A SUB SONARMAN OUT THERE?

The shaft noise would have probably helped them (WW2 sonar ops) distinguish between newer ships and the older WW1 era ships.

I was thinking in terms of maybe more rattly engines, as i said in a post earlier, but since that isn't the case, the shaft noise would do just as well as a substitute
Slowly but surely, with your help, the info you're giving me and the original idea are coming together