Noise Removal (and other effects) Advice

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kwartz
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Noise Removal (and other effects) Advice

Post by kwartz » Wed Dec 10, 2014 10:15 pm

Hello - I'm working with a (so far) unavoidable source of background noise. Wondering if I could get some advice on the best way to remove it. I've been playing around with the Noise Removal settings (and other effect settings), and have reached the limits of what I can do. Wanted to see if any one else can find a better way to remove it.

I'm shooting for trying to hit the ACX submission requirements of RMS between -23db and -18db, have nothing higher than peaks of -3db, and a maximum -60db noise floor. These are arbitrary goals, not something I'm actually required to meet. Just figured that if I can hit those goals then generally I have pretty good sounding audio.

I've attached two examples. "Test.wav" is my un-edited recording. "Text_edited.wav" is the best my feeble brain can do to improve it.

Here was my process:
1. Amplify the vocals only, setting the New Peak Amplitude to -.3db.
2. Compress the vocals only
Threshhold = -8db
Noise Floor= -35db
Ratio= 2:1
Attack! = 0.2
Release = 1.0
Make-up gain not checked
3. Noise Removal profile sample of the first two seconds
4. Noise Removal
Noise Reduction = 24
Sensitivity = 13.82
Frequency smoothing = 670
Attack!/decay time = 0.07

Any takers to educate me on how I can improve things?

Thanks, any help or suggestions is much appreciated.

steve
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Re: Noise Removal (and other effects) Advice

Post by steve » Thu Dec 11, 2014 1:23 am

kwartz wrote:Any takers to educate me on how I can improve things?
Can you wait a few weeks until the new year? I've been testing the alpha version of the new Noise Reduction effect which I've slightly modified, and in my tests it is producing much better results that the Noise Removal effect that is currently available.

Noise reduction of 24 in the current effect is probably too drastic and is likely to cause damage (metallic bubbly sounds) in the processed audio.
9/10 questions are answered in the FREQUENTLY ASKED QUESTIONS (FAQ)

kozikowski
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Re: Noise Removal (and other effects) Advice

Post by kozikowski » Thu Dec 11, 2014 1:52 am

I didn't see any samples posted.
Hearing the raw, unprocessed clip is a Really Big Deal. We can tell a lot very quickly from that.
Koz

kwartz
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Re: Noise Removal (and other effects) Advice

Post by kwartz » Thu Dec 11, 2014 4:45 pm

kozikowski wrote:I didn't see any samples posted.
Hearing the raw, unprocessed clip is a Really Big Deal. We can tell a lot very quickly from that.
Koz
Apparently I'm an idiot and forgot to post the samples. Here they are.

Thanks.
Attachments
test.wav
(770.04 KiB) Downloaded 51 times
test_edited.wav
(770.04 KiB) Downloaded 45 times

kwartz
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Re: Noise Removal (and other effects) Advice

Post by kwartz » Thu Dec 11, 2014 4:46 pm

steve wrote:
kwartz wrote:Any takers to educate me on how I can improve things?
Can you wait a few weeks until the new year? I've been testing the alpha version of the new Noise Reduction effect which I've slightly modified, and in my tests it is producing much better results that the Noise Removal effect that is currently available.

Noise reduction of 24 in the current effect is probably too drastic and is likely to cause damage (metallic bubbly sounds) in the processed audio.
I'm in no rush, so waiting a few weeks is not a problem.

Thanks!

kozikowski
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Re: Noise Removal (and other effects) Advice

Post by kozikowski » Thu Dec 11, 2014 6:42 pm

I can see one problem immediately. What did you use as the Noise Profile? The area before and after your sound sample isn't the best. You were rumbly, thumpy doing stuff back there; you didn't just stop talking. That can be deadly because it confuses Noise Removal. To Perform for Profile, hold your breath and stop moving around. Two seconds should do it, you don't have to turn blue.

If you have activities in the background such as cars starting up, TVs or conversations, you need to fix that. That condition is one of the ways to reliably kill your show. There are no good tools to fix that.

I think you overdid the patched clip. The object is gentle removal, not dead quiet backgrounds. Overdoing Noise Removal can damage the voice in the show. Start with gentle values of removal such as 9, 12 or 18. Noise Removal doesn't just attack noise. It attacks everything and it's up to you to pick the trade-off place.

You may not need to wait for Steve. I think you can do it with the work you have here.

Koz

kwartz
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Re: Noise Removal (and other effects) Advice

Post by kwartz » Thu Dec 11, 2014 6:59 pm

kozikowski wrote:I can see one problem immediately. What did you use as the Noise Profile? The area before and after your sound sample isn't the best. You were rumbly, thumpy doing stuff back there; you didn't just stop talking. That can be deadly because it confuses Noise Removal. To Perform for Profile, hold your breath and stop moving around. Two seconds should do it, you don't have to turn blue.

If you have activities in the background such as cars starting up, TVs or conversations, you need to fix that. That condition is one of the ways to reliably kill your show. There are no good tools to fix that.

I think you overdid the patched clip. The object is gentle removal, not dead quiet backgrounds. Overdoing Noise Removal can damage the voice in the show. Start with gentle values of removal such as 9, 12 or 18. Noise Removal doesn't just attack noise. It attacks everything and it's up to you to pick the trade-off place.

You may not need to wait for Steve. I think you can do it with the work you have here.

Koz
Thanks Koz. I was trying to hit the maximum -60db noise floor, and it didn't seem like lower values of noise removal were getting me there. Maybe that's because I had a pretty poor Noise Profile?

kozikowski
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Re: Noise Removal (and other effects) Advice

Post by kozikowski » Thu Dec 11, 2014 7:17 pm

I got noise values in the 70s, and again, if you're measuring a live, active room, that's not a Noise Removal problem. Noise Removal only works on periodic, extended sounds like fans or hum and buzz. It doesn't remove "Stuff I Don't Like." It has significant problems with hiss. Hiss is made up of all frequencies, so Noise Removal tries to remove the whole show.

There was also a push to rename it "Noise Reduction." Too many people are expecting it to remove noise.

Did you actually have ACX reject your posting?

Koz

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Re: Noise Removal (and other effects) Advice

Post by kozikowski » Thu Dec 11, 2014 7:20 pm

That brings up another discussion point. How are you measuring your work?
Koz

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Re: Noise Removal (and other effects) Advice

Post by kwartz » Thu Dec 11, 2014 7:20 pm

kozikowski wrote:Did you actually have ACX reject your posting?
Nope, was just using their guidelines as a goal, figured if I could meet their guidelines then I'd have fairly good audio quality.

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