Noise level

[Zenthar]

Every once in a while we se a post concerning noise level, and now on many web site we compare noise level of various components. But for most of us it is only numbers. To what each of these noise level can be compared?

30dBa, 35dBa, 40dBa, 45dBA, 50dBa, 55dBa and 60dBa?

I would like to know once and for all what is what. I think the famous FOP38 runs at about 57dBa and most people compare it to a vacuum, but what about the other levels?

 

[Guest]

57dba is nothing close to a house vacuum cleaner, a vacuum is more like 120-130dba. Your voice varies from 65-85dba. A Jet plane typically is around 140dba. A gun shot from a large caliber handgun can be as loud as 160dba. Most cars noise inside at idle is around 55-65dba. I believe the goverment has a standard that does not allow for new cars to be louder than 80dba inside the car on the highway at 65mph. But decibels are not the whole story, it is the frequency at which the noise is created. If you listened to someone talk at 85 decibels, but listened to a whine from a fire alarm at 85 decibels, the whine, high frequency, would seem louder to the human ear. So back to fans, the frequency of noise the fan produces is higher than your voice, which is in the 500-1500hz, not mhz, where as the fan would be in the 5000-10000hz range, depending on fan size and speed, which is going to seem louder and more noticeable than lower ones frequency ranges. Bass is different, and due to the low ranges of reproduction, subwoofers play in the 30hz-150hz range, are more non-directional and can be heard from long distances, high frequencys tend to more directional, and can be blocked or reduced by getting out of the directed stream of noise, kind of like closing the door to a room with a screaming baby, but if I had a subwoofer pounding away at the same noise level, you would hear it much more than the baby crying.

 

[Diemos]

Just wanted to elaborate on ZN's very good explanation. The reason the government won't let cars be over 80db is that extended exposure to sound voer that leads to hearing loss, ie. "the morning after the concert". If your concerned with the noise level of your machine you can go to a car stereo store and get a sound insulation material that will stick to the inside of your case. There you go, laterz.

"I yam what I yam!"