Q&A for How to Measure Decibels

Yes.

That is probably too loud, especially if it is bothering you.

That is quite odd if they are playing it quietly. It could be something completely unrelated to the sound system. Perhaps ask the neighbor to turn it off and see if your housemate still hears things.

Using a decibel meter as shown above can give you some level of accuracy if you simply hold the meter up to the sound source.

You can't really measure each individual without equipping everyone with separate microphones, but you can monitor the overall conversation level by using a phone app as outlined in Method 2, Step 2.

It depends on where and how you measure the dB(A). With a reading of 35dB(A) in your living room, it's likely that the sound level at your neighbors' place won't exceed 31dB(A).

In residential areas, noise levels should not exceed 55-65 decibels during the day and 45-55 decibels at night, so 55 decibels at night could disturb neighbors.

Definitely. Sound is the transfer of pressure, and it is highest at the source. As sound travels in a sphere from the origin, the pressure decreases with distance.