It might also be a way to approach BigRed's basic idea of creating a common measurment platform - if one recorded a known reference device
Gooserider, you're obviously not reading my posts very thoroughly either.
I don't understand why people are having so much trouble understanding my proposed project. It's really quite simple: It does not matter how accurate the recordings are if you don't play it back at the original loudness level!
You will get the quality of the noise but NOT
an accurate loudness level unless your playback system is calibrated.
If you set the volume too high, the difference between softer and louder noises will be exaggerated. If you set it too low, the differences will be compressed.
There is no need for any spectrum analyzer software in recordings. That is only for graphical and abstract analysis. I am recording the sounds so you can hear them for yourselves. I can assure you that the fidelity of the recordings will be very high and very consistently done. They will be high enough quality that with a high quality playback system, you will get very close facimiles of the original sounds -- if played back at the original level.
The recordings will all be made in the same room under the same conditions with the same equipment.
So how will you know where to set the volume level? By comparing a recording to the real thing under the same conditions and setting the volume control of your audio system so that the recording is at the same subjective loudness as the real thing.
You can actually try this with the recordings on page 3 of the AcoustiPack Noise Damping Kit
, about 2/3 of the way down.
There is a recording of a Panaflo 80L at 12V from 12" away
. Also a recording of a Thermaltake Volcano 7+ fan
, same conditions. (also a few others...) Pull both files down. Listen to them at the same volume setting --ie, don't touch the volume control as you swithc from one to the other. The difference is easy to hear, and you can also hear the quality of the sound.
But to hear both recordings at the correct level, the volume control must be at the right setting. You need either a Thermaltake Volcano 7+ fan
or a Panaflo 80L fan
on hand to calibrate your audio system volume level.
Hopefully you have a Panaflo. Hook it up to 12V and place it next to one speaker on something soft (so it does not vibrate). Turn the other speaker off. Now play the Panaflo fan sound file. Adjust the volume control so that the sound from the speaker is at the same level as the fan itself as you listen from 12" away.
Once you have matched the levels, your audio volume level is calibrated -- for all the recordings on that page. (There are several others) When you play any of those files, you will hear the sounds at about the same level as they were when I recorded them.
This assumes decent loudness linearity in the playback system. Which is why I mention that the higher your playback system, the more accurate and realistic the sounds will be, not only by itself but in comparison.
Now does anyone/everyone get it? Please speak up those of you who do get it! I am feeling like maybe this project should be shelved... I mean what's the point if no one understands how to make use of the results....