dB in audacity

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Andrewjames
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Post by Andrewjames » June 3rd, 2020, 11:22 am

hello all and sundry,

when im using audacity is there anything im supposed to look at that shows me the dB of the recording? i know there are the blue wavy line thing but thats not exactly precise. at present im recording a thing, saving it as a mp3 then putting it thru the checker app which is telling me the dB and then im goin back to audacity and adjusting loudness via the amplify effect...pretty much randomly and then saving it again...repeat repeat etc until i get green hooray from checker....

cant audacity tell me this info somehow and i just click a whatsit and it makes it 90dB happy days?

thanks in advance
Andrew

ej400
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Post by ej400 » June 3rd, 2020, 11:30 am

Andrewjames wrote:
June 3rd, 2020, 11:22 am
hello all and sundry,

when im using audacity is there anything im supposed to look at that shows me the dB of the recording? i know there are the blue wavy line thing but thats not exactly precise. at present im recording a thing, saving it as a mp3 then putting it thru the checker app which is telling me the dB and then im goin back to audacity and adjusting loudness via the amplify effect...pretty much randomly and then saving it again...repeat repeat etc until i get green hooray from checker....

cant audacity tell me this info somehow and i just click a whatsit and it makes it 90dB happy days?

thanks in advance
Andrew
Unfortunately, audacity does not have that. However, when for example the checker would say you need to remove 3.9 db.... you can go directly to audacity, and probably remove 4.3 and know it's right. So it should only be about one trip :D

Andrewjames
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Post by Andrewjames » June 3rd, 2020, 12:01 pm

hi
thanks for the reply, so how do i remove 4.3dB for example? i select all the recording, go to effects: amplify

the dialog then says "Amplification (dB) " and a box

under that is a slider

under that it says "new peack amplitude (dB) and another box

then a check box for ' allow clipping'

....would i just type -4.3 in the first box and press ok? (i just did that and it shrank the wibbly lines pretty tiny!)

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Post by mightyfelix » June 3rd, 2020, 12:28 pm

Checker will tell you, under the "Information" tab, how many decibels your recording is. You'll want to remember that the goal is 89. So, if Checker says the recording is 93 dB, you would highlight the recording, then go to Effects>Amplify. In the first box, you would type -4 (89-93). It's important that you do NOT check the box that says Allow Clipping.

Elijah is right that Audacity doesn't come with a feature to measure volume, however, you can download an extra plugin that will do it. It's called ReplayGain. You can find more info, along with a link to download it, here: https://wiki.librivox.org/index.php?title=Measuring_Volume_within_Audacity I have heard that these kind of plugins are not working well with the newest version of Audacity, but I haven't tried the newest release myself yet.

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Post by philchenevert » June 3rd, 2020, 1:02 pm

Another tool is to use your eyes to estimate as you go along http://www.youtube.com/watch?v=w9WF82rf81o
It's not precise at all but has the benefit of knowing approximately the volume of your recording as you go along.
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ej400
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Post by ej400 » June 3rd, 2020, 1:30 pm

Andrewjames wrote:
June 3rd, 2020, 12:01 pm
....would i just type -4.3 in the first box and press ok? (i just did that and it shrank the wibbly lines pretty tiny!)
Yes and No. Depending on how much the checker says you need to remove, is what you will need to type in. But that's how you would amplify.

Going back to what Devorah said,
mightyfelix wrote:
June 3rd, 2020, 12:28 pm
It's important that you do NOT check the box that says Allow Clipping.
If you need any more help, just let us know :D

loon
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Post by loon » June 3rd, 2020, 1:43 pm

Once you get a recording at just the right level play it in Audacity and keep an eye on those meters. From that you should be able to tell if your volume as you record is just about correct or too quiet or too loud.

I've seen lots of 40 or 50 year old recordings that fully meet today's specifications, and the meters available to pro recording engineers in those days were no better than your Audacity meters.
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Andrewjames
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Post by Andrewjames » June 4th, 2020, 6:51 am

thanku all for your help!

audiomike
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Post by audiomike » June 4th, 2020, 7:46 am

Normalize to -3 dB. That will usually get you in the ballpark unless your audio has a lot of spikes holding the rest of it down.

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Post by TriciaG » June 4th, 2020, 8:11 am

unless your audio has a lot of spikes holding the rest of it down
Unless your audio has even ONE spike holding the rest of it down. :) For this reason I don't recommend the Normalization effect until a reader has a very good feel for their volume and voice control.

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If Checker says a recording is at 85.4, then amplify by about 4 dB, to get it a little over 89. It doesn't have to be exact, and I personally like to err slightly on the louder side. If you can use ReplayGain, it'll tell you how much to amplify, plus or minus - but even there, I like to err a little on the louder side since I find ReplayGain tends to aim a little low. :)
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