sunday's stupid questions: is quieting a Detroit possible?

[MarioG]

So while checking the fluids on the mains with a beer In hand, I started to wonder if it is even possible to quiet the detroits down some. Although I have become accustomed to the greyhound bus sound over the years, I wonder if it's possible to enclose the mains with a generator enclosure style sound shield? Probably not practical but makes for a fun topic.
Mario

 

[jim rosenthal]

Well, you could line the engine rooms with Soundown or something like it. It would cost you a lot.

For all that money, you could buy a lot of 1) beer 2) diesel 3) REALLY good noise-cancelling headphones. You could buy all three, really.

 

[Salty Dame]

I'm gonna follow this thread closely.

 

[Boatnut]

Sound proofing the salon walls will help a lot. We elected to do this rather than trying to sound proof the engine room. It made a big difference in the salon area, which was my concern, for passenger comfort, no one sleeps when the boat is underway anyway. The sound proofing in the floor is still factory installed. Not the greatest, but the walls did it for us.

It's really too bad we have to put up with stupid responses with dumb comments. Isn't this supposed to be the model perfect boating forum, no politics, no arguing or disagreeing especially with moderators, no cussing.

 

[Boatsb]

Yes its possible and not as simple as adding soundown.

Noise is not simple. It has to be addressed with more than 1 type of abatement.

 

[dottieshusband]

It's like asking if you can quiet a fire breathing big block, well, yes you could... But why would you? I love the sound of the buzzin dozen, almost as much as the smell of diesel exhaust on a cool fall morning!

 

[MarioG]

Lead blanket enclosure. The hanging type?

 

[magnawake]

It's like asking if you can quiet a fire breathing big block, well, yes you could... But why would you? I love the sound of the buzzin dozen, almost as much as the smell of diesel exhaust on a cool fall morning!

Yeah really !!! That drone sounds super cool. Tim the "Tool Man" Taylor would love it also. Uugh, Ugh, Ugh....I only hear the exhaust from the outside. My friends 70's 6-71 sound way cool too.

 

[jim rosenthal]

Scott, have you done this on customers' boats and what was the procedure that you used? Even if he doesn't do it, I'm still interested in what you used and how it turned out.

 

[rsmith]

If you have big bucks their using ANR in aircraft cabins now. Speakers set through the cabin transmit a sound wave that deadens the noise waves. Bose developed this technology for aircraft head sets.

 

[saltshaker]

Detroits need a fair amount of air to breathe properly. Not sure you'd want an enclosure around them. I'd also be concerned on how it would effect cooling. Soundproofing is the way to go. I did the entire ER on my 46C with Soundown and the results were great. I replaced all the original sound proofing on the ER overhead and bulkheads. The key is to cover any gaps. When we first ran the boat without the carpet in, the noise reduction was good. After installing the Soundown carpet underlayment and then carpet, the difference was huge. As Scott said, it takes a bit more than just one produce. I had the primary stuff made of a vinyl barrier sandwiched with closed cell foam and a mylar outer layer. Insulation was 4" thick. The salon deck was covered in a closed cell foam that was glued to the carpet. Mine interior was redone so I wasn't able to get behind the salon walls and soundproof them but that makes a huge difference as it's a direct open connection to the ER. Insulating that are will probably give you the most bang for the buck. Look at this post and you'll see what I mean.
http://www.samsmarine.com/forums/showthread.php?23835-Inside-a-43-DC-Really-Inside

 

[Pascal]

First thing to check is sealing and insulation on saloon floor / ER ceiling. Very easy for sound to come thru the hatches openings. You have wood not carpet on Siboney, right? Probably makes it worst and limits your notions to the ER ceiling

 

[savarese1]

Our Detroit nauturals have some kind of massive muffler on the back of the engine. Some mechanics have said the have never seen that before. We can easily have a conversation in the Salon or aft deck. The muffles do have a detroit diesel tag so they must have originally come from the factory.

 

[mike]

Another large source of noise is the air intake, the roots blowers are very loud esp on naturals, turbo´s less so. However, not too much can be done to quit down the air intakes. Additionally, vibration isolation of the engines helps, had a significent drop in low frequency sound after going to newer isolation style mounts.

 

[carolinacoast]

lightspeed or bose aviation headsets allow anyone to talk on the phone in the salon underway at cruise with no hint of noise to whoever you are talking to. Other than that, I like the sound of the detroits. Agree that modifying the airflow in someway may be problematic.

 

[madhatter1]

I have heard several times over the years of using old down pillows being enclosed in fire retardant blankets cut to dressed to the sizes of sections that make up the sole and hatches. These are attached using aluminum rail and stainless screws. One boat had them wrapped around the mufflers under the aft cabin to reduce noise there as well while underway.

 

[madhatter1]

What?? No comments on my post. OK, April fools and no help to the OP.

 

[DCMY #92]

I agree with a previous post that the air volume consumed by these engines pretty much eliminate an enclosure. Plus, what a pain they would during pre-flight checks. If you look at the thread "1965 41 DCMY Refit" you'll see what I did regarding reducing engine room sound. The recent thread "Inside a 43 DCMY, Really inside" also identifies the big problem. The saloon walls are 1/4" plywood. The void space behind the walls communicates with the engine room via the air intakes. So, as the Soundown engineer put it, Hatteras invited the engines into the saloon. The previous post suggesting that soundproofing the back side of the saloon walls would be way cheaper than the solution I chose. As someone else also mentioned, sealing the engine hatches and any other "short circuits" for sound is critical.

 

[MarioG]

I agree there are different frequencies of sound that the engines give off which makes sound isolation difficult. I have noticed that there is more sound without the salon carpeting. It would be nice if there was a simpler solution. Oh well, rumble on!

 

[pmorehart]

try sailors solutions web site. They sell some good panels which should tone it down quite a bit. reasonable price. Easy installation as well. Just peel backing and apply as needed. Good luck.