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My comment was in response to another that encouraged the op to pay attention to noise ratings. Even if I lived in the country with no neighbors, I’d follow that advice. The “db” rating is a logarithmic scale, not linear, so even an increase of a few db is a huge increase in noise/volume. Why endure the disruption needlessly when there are manufacturers who pay attention to noise attenuation?
That being said, the difference between 70dB and 80dB SPL is not a huge difference. However, as noted, the SPL level is a logarithmic method...I can assure you that while that 10dB difference is quite noticeable, it's likely not objectionable. Now going from 110dB to 120dB it's a seemingly HUGE difference! 120dB to 130dB is the difference between really loud and painfully loud. The difference between 60dB and 70dB is very insignificant. The more important stat would be SIL (Sound Intensity Level).

In the country, the ambient noise level...or noise floor can be quite low. The same is true in the city, though it will generally be a bit higher noise floor. If you have a genset making 75db in the country with a noise floor of 45dB then you have 30dB of gain over the noise floor. In the city a 82dB genset may actually seem less offensive since the noise floor might be 55dB...a 27dB gain over the ambient noise floor...interesting isn't it?

My take is this...if it's keeping me going I don't care if it's got a straight pipe on it!!
 
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Well said!

70 db is 10 times louder than 60 dB.
80 db is 10 times louder than 70 dB.
90 db is 10 times louder than 80 dB, or 1,000 times louder than the original 60 dB.

Honda has some very quiet generators, 52 dB to 65 dB, but most are small portables. Their inverter line is extremely quiet, <50 dB, but far too small. Cal
This is incorrect...though the Honda gensets are quite quiet.

It takes on the order of a 10dB increase to be perceived as TWICE as loud.

70dB is twice as loud as 60dB. The numbers are not consistent though as SPL is not a LINEAR scale. It is close enough to use this measure between 70db & 120dB. Beyond 120dB, it will take less increase in SPL to be perceived as twice as loud.

You can also get sound propagation "boundry reinforcement" if the unit is right next to a building it can make the sound 3dB louder in the direction opposite the wall. Sound also decreases over distance fairly rapidly. I could get into some rather complex formula's for this, but then we'd have to have a good calculator or at least take our shoes off...LOL

Now, I think what you might have been referring to is that in audio, it takes on the order of 10 times the power to play something twice as loud. For every 3dB increase in SPL it takes twice the amplifier power. For example, if you have a speaker rated at [email protected]/1M...meaning it takes 1 watt of amplifier power to produce 90dB at 1 meter from the source, it takes 10 watts to reach 100dB SPL. To reach 120dB you now need 1024 watts...or ten times the power of the 100dB level at 10 watts. If the speaker was capable...very few are...it would take 2048 watts to gain another 10dB to 130dB. We have only doubled the sound level 3 times, yet we have went from 1 watt to over 2000 watts to do it.

Please do not use home speakers to verify this...you will likely have a woofer now lying on the floor and a small fire...or both...LOL! I highly recommend using higher end professional (Audio PA) equipment for verification...and hearing protection!!

I have used, installed, tested and reviewed audio equipment for over 25 years.
 
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About 8 years ago I was getting estimates for a genset for the business where I was the Operations Manager. Going "by the book" it was going to require a 22kw unit. He then asked me how many of these things would actually be used during a power outage. I called the shop foreman in and we discussed our shop needs during an outage as opposed to our wants. The office was very easy to figure. After going through the shops needs, we found we needed nowhere near that large of a unit. A 15kw unit was determined to be plenty big enough and actually gave us a good safety margin. The cost difference was substantial along with the fuel consumed. Very rarely will all of your electrical demand reach a maximum level for each unit...and simply put they aren't all at maximum draw at the same time. Keep that in mind...never overbuy for a decent genset...especially when on LP!!
 

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A genset will not increase the value of a home unfortunately....only to you.
 
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