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One of the drawbacks often mentioned when running a portable generator is the noise which is annoying and alerts the neighbors you have power. How feasible do you think a baffle box to reduce noise would be?

My idea is to build a box made of plywood and 2x4s that's big enough to allow at least 1 - 2' clearance around the entire generator. There would be a hole for the exhaust and a smaller one for the cord. Then I would staple pillows to the inside of the box. I got the idea after reading a book on sniper techniques in which the author suggested lining a car trunk with pillows to dampen the sound of shots fired by a sniper lying in the trunk.

My concern is the potential fire hazard. Do they run hot? I don't currently have a generator.
 

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reluctant sinner
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You will want a baffle box and a much better muffler. The box should be slatted and have the 'boards' direct the sound upward. Yes generators run hot and require good air flow for cooling.

You need to be able to easily get to the genny for refueling and maintenance. It should also be grounded and chained/bolted down.

Depending on the size of the unit a cammo dog house could be erected over it and tipped back for operation. Perhaps a box fan using some of the power to provide forced air cooling.

1800 RPM units tend to be quieter and last longer. Inverter types can provide more economy at the lower end of a units capacity. Units that can be doubled up can be a good option for limited higher capacity requirements.
 

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Easy way is to just box in the generator with some iso panels. The motor makes a lot of noise that is not exhaust related. Getting that noise directed up works well. Any dense fiberboard type insulation will work. Just set three or four panels around genny. This directs and causes the noise to go up. With the noise going up, also makes harder to figure out which direction it is coming from.
 
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They run plenty hot and unless you get the heat out, the oil will break down and the engine will fail. Fuel will overheat and you will have vapor lock, if not fire.

Soundproofing material can burn and if the fire is near your dwelling it will spread.

Start with a better muffler system and then build a shelter that has plenty of airflow and use deflecting baffles to break up the sound waves.

There are better quieter, generators these days that have invertors. Unless you are powering a machine shop or HVAC system, you should consider them.

Sent from my SM-T350 using Tapatalk
 

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If my main worry was someone knowing that I had power, I'd probably build a dog house insulated with thick foam panels and port the exhaust through a flex pipe into a motorcycle muffler like a Gold Wing uses. Those bikes have big motors but you can hardly hear them. Same system with a filter would feed the carb.
 

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There are plenty of Youtube videos on this subject.

It's not hard to reduce the noise level, but there has to be lots of airflow for combustion and cooling.
 

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Sound proof/resistant walls in old theatre are made of 2 plys of sheetrock on each side of 6” studs, with insulation between.

Also mineral wool batting about 2” thick is good for sound proofing. It comes in 2ft x4ft sheets.
 

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My genarator Is in the corner of a 8x10 its sitting about 18 “ off the floor with a tractor muffler running out and up the wall .
With the door closed it just hums .
The flapper tapping on the top of the muffler makes more noise then the motor .
My genarator is a Honda 2800 watt open frame inverter .
It mostly runs in the winter when it cold .
 

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Dog Lives Matter
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The noise should be a concern. I've told this story many times in this forum. Back in the 1990s a huge storm went through Minnesota and knocked out the power in my area for 5 days. I had a small 3500 watt Honda generator that I started up to keep my refrigerator cold. Every neighbor showed up at my door with a long power cord in hand. I ran shifts and gave each an hour of power at a time, and instructed them to only run one refrigerator. Only one neighbor disregarded my instructions. He had a large commercial freezer in his garage that bogged down the generator, so I cut him off.

The caveat is that not a single neighbor offered to help pay for gas. Their attitude was, "Su generador es mi generador."

There is good reason to keep your generator quiet if you wish to maintain relationships with your neighbors.
 

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If you don't already own a generator start by buying an inverter generator. They are already extremely quiet (they are also very expensive per watt) from there put it in an open topped box to direct the sound up and you would probably have a generator that can't be heard 100 feet away.
 

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Dog Lives Matter
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Great ideas! I'll search on YT for some videos.
There are tons of videos on YouTube. Just be careful choosing the design. You need to stifle the sound while providing airflow for cooling. Several of the videos that I watched only focused on the sound.

There are two sounds to be aware of: mechanical sounds from the engine and exhaust sounds from combustion.

Without good airflow, a box will heat up rapidly and the engine may choke.

It might be a good idea if members start posting the YouTube videos with the best designs in this thread.
 

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Besides the exhaust, the intake generates noise also. The generators design to be quieter have bigger better mufflers and also sound baffles designed into the intake housing.

I put an old ATV muffler on my 11HP log splitter engine and it made a world of difference.

For generators with wheels, inflatable tires will dampen vibration better.
I placed O-rings and rubber washers where there were metal to metal bolted connections.
Look for any rattles, like loose or folding handles and address those items.
On concrete, I roll mine onto a piece of old carpeting with padding underneath.

You can't get rid of the actual whirrring noise of the generator windings, nor the clatter from the engine valves and such. That's where enclosures come into play.

An enclosure should have fan forced air blowing from the intake side of the generator engine toward the exhaust end, with plenty of opening for the hot air to be exhausted.
Utube for many ideas.
 

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covfefe
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attach a hose (non-flammable) to the exhaust, and put the free end into a 5 gallon bucket of water.
 

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Just a plain box you put the generator in can actually make the generator louder. You need sound absorbing material and there is where it can get pricey and things get hot inside.
 

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How about a dog house next to your genie and a big dog in the doghouse?

Ya'll shoot straight and stay safe out there.

WW

WE ALL WANT TO BE FREE, BUT VERY FEW OF US WANT TO BE BRAVE. FOR ALL OF US TO BE FREE, A FEW MORE OF US, ESPECIALLY NOW, MUST BE BRAVE, AND THAT'S THE HISTORY OF AMERICA

K. R. Carleson - Navigator B-24J
 
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