Raising volume not hiss (how to?)

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Black Dog Bluez
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Raising volume not hiss (how to?)

Post by Black Dog Bluez » Sun Dec 28, 2014 11:14 pm

is there a way to increase loudness of a track without increasing the hiss? I tried setting the compressor floor above what seems to be where the hiss is -for instance at silence hiss around -43 dB so I set compressor floor to 40 or 35 yet still the hiss is raised in the end. the song is louder but the hiss is too.. tried with peak compression and without (RMS) as well as the SC4 compressor.

kozikowski
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Re: Raising volume not hiss (how to?)

Post by kozikowski » Sun Dec 28, 2014 11:52 pm

You forgot Noise Gate...

http://wiki.audacityteam.org/wiki/Nyqui ... Noise_Gate

and Effect > Noise Removal.

http://manual.audacityteam.org/o/man/noise_removal.html

Hiss is death because you couldn't design a more perfect interference. Noise Removal tries to select the tones and pitches in your "noise" and it subtracts them from the show. Hiss has some of all tones in it, so Noise Removal tries to remove the whole show.

Not so good. How about Noise Gate? All sounds below a certain level are deleted. That's less desirable than you think because it also tends to chop off beginnings and ends of words and give robotic sounds if you're not careful. And if you change anything in the show, you have to go through and set it again.

Attached: People promote their custom microphone preamplifiers (MicPre) for a reason. "MIDAS-Designed"...etc. Good PicPres are well-behaved and don't make very much noise. No ffffffffffff, or very little.

So no. There's no good Post Production way out of this. Each of those tools may help a Little Bit (use very gentle Noise Removal) and the combination may get you over the hump, but you will have to go through all that for every show unless you change how you shoot it.

Best to shoot it well at the beginning.

Koz
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Black Dog Bluez
Posts: 294
Joined: Sat Jun 16, 2012 9:43 pm
Operating System: Windows 7

Re: Raising volume not hiss (how to?)

Post by Black Dog Bluez » Mon Dec 29, 2014 7:54 pm

Thanks Koz--I hate to use the Noise Removal--as you know, it's a trade-off. Downside is it takes some of the good away too/as you wrote best to solve the problem before or during recording as opposed to 'post'. Didn't know about the gate-- will experiment/but sounds similar per trading off--. I just thought a compressor could actually just raise the good parts and leave the floor(?) as it implies. But I'm sure it's much more complicated then that--if the hiss is actually all over as opposed to neatly packed on the floor--just guessing--it's intertwined throughout--is why the compressor still elevates hiss in the end result/when raising volume after compression or using peak compression.

kozikowski
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Re: Raising volume not hiss (how to?)

Post by kozikowski » Mon Dec 29, 2014 9:57 pm

It's not more complicated than that. It's job is to raise the noise in relation to the show. It's normal job is to reduce extreme or destructive sound peaks in relation to the average show volume, but the fact remains it shrinks (compresses) the loud parts to match the quiet ones.

You might like a Compander: a compressor that will work both directions. You would use the expander portion of the tool. We don't have one of those (that I know of).

The normal poster who complains about this also says the words: "I was given this sound file" neatly divorcing them from the shooting process. It also suggests the shooters knew what they were getting into and the the poster doesn't.

Koz

kozikowski
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Re: Raising volume not hiss (how to?)

Post by kozikowski » Mon Dec 29, 2014 10:00 pm

You are perfectly correct. The fact that the ffffffffff is there in addition to the voices is what kills you. There is no good recovery for hissy voices.

The video people have a bad joke called "The Reshoot Filter." You take the camera out.........

Koz

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