Normalise

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Kristen
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Post by Kristen » September 26th, 2005, 12:45 am

When editing your reading, a quick fix of uneven levels (variations in volume) is to Normalise. This will soften the loudest passages and boost the quieter ones. It's not going to fix every variation in the recording, but it is a good first step to improving the recording overall.
Kristen
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Aaron
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Post by Aaron » September 29th, 2005, 8:58 pm

Kristen, I think you're confusing normalization with compression (or is it limiting? I forget).

Normalization just boosts everything evenly until the loudest passage is at maximum level before distortion. It definitely doesn't make a loud passage quieter.

Kristen
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Post by Kristen » September 30th, 2005, 6:02 am

Good point. I was trying to explain that Normalise evens out the levels, but not expressing myself very well. I know it doesn't limit or compress. :-)
Kristen
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vee
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Post by vee » November 16th, 2005, 7:42 pm

Normalizing is indeed different from compression. When you normalize you can raise and lower peak levels and RMS (average loudness) of the recording. So let's say you have a recording at -12 db peak and you want it at -6 you would raise everything by -6db. So everything is getting louder an equal amount.

Compressors can raise the perceived loudness of a recording by reducing the dynamic range. Basically it reduces the difference between the loudest and softest items. It does this by reducing the loudest items. You can set a compressor to reduce different levels different amounts so that it sounds more natural instead of just cutting off.

There's kindof a debate as to what is really best to use. Compressors are probably better if there are lots of different speakers in the same recording or lots of instruments. Normalizing is probably more useful for a single speaker since our volume variations are probably intentional.

Just an additional note. You can normalize down too. If your recordings are way too loud you can normalize to a lower dB level to make it a little more comfortable to listen too. It could probably help with lowering some of the background noise too. I use a Adobe Audition to do my recordings so I can remove some of the background noise with a plugin. It's actually quite cool and easy to use, but Audition is a bit expensive.

Hope that helps. I'm sure there are a lot of people who understand this better than me and I may very well be wrong, but this is how I use it.
Chris Vee
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rfrancis
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Post by rfrancis » November 16th, 2005, 9:50 pm

Compression in moderation can add some bulk to the sound generally (by keeping it from being limited by peaks) -- I have found it useful in my Bible reading podcast. But too much, and the sound turns quite mushy.

And yeah, like vee said, in a dramatic reading you're likely to make deliberate volume changes so probably don't want to use compression. (I don't use it on my talk podcast for the same reason -- I vary my volume on purpose.)

-R

BradBush
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Post by BradBush » November 16th, 2005, 10:21 pm

See article I posted in the recording forum:
http://librivox.org/forum/viewtopic.php?t=101 . I use a very similar setup in my podcasts (gate, compressor, de-essor,reverb on tracks plus limiter on the main output track). Checkout a short example of the type of sound I get: http://home.comcast.net/~bush.brad/librivox/ancient_bard_blake_jbb.mp3 .

Now some comments/opinions on the above main thread ...

Normalize = automatic chnange in volume to make all parts of a recording as loud as they can be without the loudest clipping ("going over and sounding bad / distorting)

Compression = lowers they dynamic range or (in english) makes the louds softer while keeping the softs the same volume (you can then raise the volume to get the "percieved" loudness previously mentioned)

Almost every modern published audio recording has some compression on it. It makes the "volume" sound louder in pop music (important in today's compression/volume wars), but it also takes a bit of the harshness out (as most compressors, even software ones, have a "character" that softens the sound). People like recording to tape still because of the natural compression. Note that compression will take out some of the ups and downs of the volume, and thus some of the emotion, so use it judiciously.

I have rarely found a need for normalization, as the same function can usually be done "non-destructively" using the gain makeup in your editor (track volume, track fader, whatever your editor calls it).

All of these methods of making your recording louder will also raise the "noise floor" and thus make your noise louder. If you are recordning at 16bit, the most important thing is to get the "hottest" signal you can, turn off the AC, replace loud fans in your computer) I have my computer totally silent as it has no video card fan, and special fans for CPU and box that are 120mm and very quiet.

If you are recording in 24 bit, you have more "data" in your recordings, and the noise with therfore be farther away from your signal, and you don't have to worry about recording so "hot" (but then you have to figure out how to dither to 16 bit - another topic). I personally record at 24 bit 44.1khz and dither down to 16/22 wav before converting to MP3.

I figured out all of this because I use my computer as a music studio, and just happened to start podcasting/librivoxing to put it to another use.

OK, I'll quit being the recording geek. I kind of like this stuff though.

Brad

donnawinters400
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Post by donnawinters400 » June 13th, 2012, 2:11 pm

This is for Brad:

You seem so involved in all this tech stuff. I am off topic, but I wanted to ask your expert opinion. I have this hissing sound in my tracks, and I think is from the pc, is an old desktop. I tried putting blankets on it, but that hissing is still there, I did the amplify + noise removal, but the hissing stays put. Could you give me an advice that doesn't involve removing the computer fan, because I believe it would overheat.
Thanks
DW

annise
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Post by annise » June 13th, 2012, 2:26 pm

Brad hasn't been around for a while. I know you have been having real problems - I wouldn't describe any fan noise I have heard as a hiss , more a rattle but I haven't been involved in your earlier attempts. Perhaps post a sample just as it comes out when you read in the listeners wanted thread and we will see if we can pick out a better suggestion , it is much harder once you have amplified and noiseclesned . Don't worry what your readand leave a section with the microphone on and no speech

Anne

TriciaG
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Post by TriciaG » June 13th, 2012, 2:36 pm

Donna posted a thread for help here: viewtopic.php?f=23&t=40363

I think we should continue to help her there and not in multiple threads, as that would be duplicating efforts. :)
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annise
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Post by annise » June 13th, 2012, 3:06 pm

Sorry - I didn't make it clear , that is where I wanted her to post , not here :D

Anne

donnawinters400
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Post by donnawinters400 » June 16th, 2012, 7:36 am

HI:
Thanks so much for trying, sorry that my desperation made me post in two areas. I wanted SOS :), I'll stay put in the other area as you suggest. Thanks Annise and TriciaG.
DW

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