Understanding the wave form

[eraos]

I guess this question belongs in the forum.

How do you read a wave form (if that's even what it's called)?

What I'm asking is, for example, what does the shape of the audio file tell me:
http://www.freewebs.com/eraos/pictures/gwmain.png
--the photo is from goldwave.com--

And what does the numbers mean, 0 +-.5, +-1?

Also, relating to that question, on a compressor, when you set the threshold to, say, -10, what does that mean? What does -10 signify? 10dB below something?

I apologize for if I confused anybody with my poorly worded question.

 

[mshilarious]

I guess this question belongs in the forum.

How do you read a wave form (if that's even what it's called)?

What I'm asking is, for example, what does the shape of the audio file tell me:
http://www.freewebs.com/eraos/pictures/gwmain.png
--the photo is from goldwave.com--

And what does the numbers mean, 0 +-.5, +-1?

Well, what that wave says is that it isn't very loud (because it only takes of half of the range available), and there are lots of transient peaks--those frequent spikes a little over +-0.5.

Ideally you want to record so those transient peaks are closer to, but do not exceed the top, and your average level is more like .75 on the chart. I don't know how that scale is calibrated though, maybe .5 is -12dBFS. Somebody else here will know.

But now that you've recorded, you only option is compressing with an extra amount of makeup gain to get the levels up, which means that you've lost some dynamic range. Based upon the waveform, you probably won't suffer that much because there aren't any really quiet parts.

Also, relating to that question, on a compressor, when you set the threshold to, say, -10, what does that mean? What does -10 signify? 10dB below something?

Yes a DAW compressor will ordinarily be labeled in dBFS. In that case -10 would mean the compressor will start reducing gain at -10dBFS.

With the wave you have, you'd need something like that for a threshold, say a 3:1 ratio, and about +9dB of makeup gain. But again that's just a guess because I don't know the scale of the wave.

 

[eraos]

Yes a DAW compressor will ordinarily be labeled in dBFS. In that case -10 would mean the compressor will start reducing gain at -10dBFS.

so, if the label is dBFS, which I looked up (acronym.com...), a -10 basically means that the threshold is set at 10 dB below the maximum value?



Why, on the wave form thing, is there a positive and negative area of sound for both left and right channels? What I mean is, why is the audio form ...uh....."symmetrical with respect to 0"? Why not just an entirely positive area?
Again, I'm not sure if Im' wording that clearly. . .

 

[mshilarious]

so, if the label is dBFS, which I looked up (acronym.com...), a -10 basically means that the threshold is set at 10 dB below the maximum value?

Yes.

Why, on the wave form thing, is there a positive and negative area of sound for both left and right channels? What I mean is, why is the audio form ...uh....."symmetrical with respect to 0"? Why not just an entirely positive area?
Again, I'm not sure if Im' wording that clearly. . .

Because audio signals are AC, so they swing from positive to negative voltage. This is different than what you are used to seeing on a VU meter, where the signal is always shown as a positive amplitude, but it's the convention for digital audio.