How Do You Read SPL Charts?

Frequently asked questions and the answers to them.

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How Do You Read SPL Charts?

#1 Post by djnbmix » Sat Jul 08, 2006 10:20 pm

I really don't know how to read them, can somebody explain how please.

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#2 Post by LelandCrooks » Sun Jul 09, 2006 6:53 am

From left to right on the bottom scale is the frequency. The vertical axis is the volume, measured in db. The more the merrier. You find your desired freqency, go up until you hit the measured line, read across to the the db vertical axis and that's the volume at that spot. The flatter the line overall the better it is, is the accepted rule. The higher the line the louder it is. Charts are supposed to be drawn with the microphone 1 meter away, with 1 watt into the speaker. Watch that, lots of companies cheat. With horns, the measurement is taken farther away, then the 1w/1m is calculated.
If it's too loud, you're even older than me! Like me.