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Gear / Technical Help => Post-Processing, Computer / Streaming / Internet Devices & Related Activity => Topic started by: bconnolly on January 29, 2006, 03:49:01 AM

Title: General normalization help with Audacity
Post by: bconnolly on January 29, 2006, 03:49:01 AM
I'm trying to figure out the best all-around way to boost the volume of my recordings in Audacity.  I know that hard limiting and normalization is the way to go about this, but I'm no good at looking the waveform and saying "yup, I have to do this and this".

Here are some screencaps of the waveform:

zoomed in:
(http://img98.imageshack.us/img98/5037/zoomedin6so.th.jpg) (http://img98.imageshack.us/my.php?image=zoomedin6so.jpg)

regular:
(http://img98.imageshack.us/img98/8240/regular9kc.th.jpg) (http://img98.imageshack.us/my.php?image=regular9kc.jpg)

Pay no mind to the fact that the channels are different volumes (isn't a huge deal to me) but I'm trying to boost the overall volume of the recording and I'm not quite sure how to do that properly.
Title: Re: General normalization help with Audacity
Post by: Roving Sign on January 29, 2006, 11:17:53 AM
In Audacity - use the "Amplify" function...

In this case, I would apply it to each channel seperately...use the "Split Stereo Track" fucntion first...(see attachment)

Then Select All in each channel and apply the Amplify function...make sure the "Allow Clipping" box is unchecked.

Then "Make Stereo Track" (same place as the Split function)

Save and export...



Title: Re: General normalization help with Audacity
Post by: bconnolly on January 29, 2006, 02:27:25 PM
If I try to apply amplify to one of the channel and I uncheck "allow clipping" it doesn't let me execute the effect ("OK" is greyed out).  Even if I move the slider one notch it greys out the OK button.

Does this mean I can't amplify the tracks without having issues with clipping?
Title: Re: General normalization help with Audacity
Post by: Roving Sign on January 29, 2006, 02:37:05 PM
You need to save the file first...(Audacity creates a .aup file) It doesnt like to do things without the aup file.

So  -

1 open the wav

2 Save as

3 now edit...

That will do it...

Remember - the workflow in Audacity is slightly different than other editors - Audacity breaks wavs into little chunks...makes editing use less CPU power - when you export it sews it all back together...I think thats why they call it "Audacity" All the editing changes are stored in the .aup file...you need create that first...
Title: Re: General normalization help with Audacity
Post by: bconnolly on January 29, 2006, 02:43:43 PM
You need to save the file first...(Audacity creates a .aup file) It doesnt like to do things without the aup file.

So  -

1 open the wav

2 Save as

3 now edit...

That will do it...

Remember - the workflow in Audacity is slightly different than other editors - Audacity breaks wavs into little chunks...makes editing use less CPU power - when you export it sews it all back together...I think thats why they call it "Audacity" All the editing changes are stored in the .aup file...you need create that first...

I actually already had an aup file created (from some slight editing last night).  I think the reason it says I'll clip is that I have a slight "pop" in the beginning of the recording and it's a fairly large single-line spike... it might be reading that as "clipping".
Title: Re: General normalization help with Audacity
Post by: Roving Sign on January 29, 2006, 02:46:06 PM
Yep - if its a JB3 - almost all of them place a digi-spike right at the beginning of the track...perhaps the MT does the same...

Trim that off and you will be good to go...
Title: Re: General normalization help with Audacity
Post by: bconnolly on January 29, 2006, 02:49:22 PM
Yep - if its a JB3 - almost all of them place a digi-spike right at the beginning of the track...perhaps the MT does the same...

Trim that off and you will be good to go...

No it's not at the VERY beginning.  Just in the first minute or so.  I think someone bumped my stand pretty hard.
Title: Re: General normalization help with Audacity
Post by: Roving Sign on January 29, 2006, 02:57:50 PM
ahhh - gotcha...maybe tone that down with a high-pass filter - (bass cut)
Title: Re: General normalization help with Audacity
Post by: kfrinkle on January 29, 2006, 11:00:11 PM
if it is one blip, you can probably just cut that piece without any noticeable effect...
Title: Re: General normalization help with Audacity
Post by: flipp on January 30, 2006, 07:06:16 AM
If it's just one spike, zoom in (keep zooming) until you can use the pencil tool to draw the peak down to the same level as the rest of the wave. Good for the wook bumpin the stand and balloons hitting the mics.
Title: Re: General normalization help with Audacity
Post by: bconnolly on February 25, 2006, 05:03:11 PM
Rather than start a new thread, I thought I'd just use this one since it's basically the same question but witht a different recording.  If my peak level for my recording is -12db, what is a safe db to normalize it to?
Title: Re: General normalization help with Audacity
Post by: Brian Skalinder on February 25, 2006, 05:14:41 PM
Rather than start a new thread, I thought I'd just use this one since it's basically the same question but witht a different recording.  If my peak level for my recording is -12db, what is a safe db to normalize it to?

If your highest peak is -12 dB, then normalize to - or just under - 0 dB.  So...add +12 dB, or +11.5 dB.
Title: Re: General normalization help with Audacity
Post by: bconnolly on February 25, 2006, 05:30:15 PM
Rather than start a new thread, I thought I'd just use this one since it's basically the same question but witht a different recording.  If my peak level for my recording is -12db, what is a safe db to normalize it to?

If your highest peak is -12 dB, then normalize to - or just under - 0 dB.  So...add +12 dB, or +11.5 dB.

At what point will you bring it up too much and distort the recording?  I guess what I'm saying is... how weak does the recording level have to be to make a -0db normalization less than ideal? I thought -12db was pretty low...
Title: Re: General normalization help with Audacity
Post by: Brian Skalinder on February 25, 2006, 06:00:30 PM
At what point will you bring it up too much and distort the recording?  I guess what I'm saying is... how weak does the recording level have to be to make a -0db normalization less than ideal? I thought -12db was pretty low...

The recording won't distort simply by raising levels, unless you jack 'em up above 0dB.  You will, however, raise the noise along with the music.  But you're gonna do that anyway, regardless - either it happens in the digital realm in post-production, or during playback.  That's why it's so important to set levels as high as possible (without clipping) at the time of recording.