Noise Floor

Narrating and Producing Audiobooks.
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BrittanyS
Posts: 29
Joined: Wed Sep 05, 2018 2:09 am
Operating System: Windows 10

Noise Floor

Post by BrittanyS » Wed Sep 05, 2018 2:16 am

Good evening,

I am recording my first ever audiobook. Unfortunately, I chose a long one (3.5 hours) and after watching a lot of YouTube videos, I thought I had the editing under control. I guess not, because I submitted the audiobook and received notification of items that need fixing. :( All of the items the picked out I can fix with minimal effort, but one of them I am entirely clueless on. It stated the requirement is a maximum of -60db noise floor.

I downloaded a plug in titled ACX check, which runs its check and states I meet ACX requirements, but it didn't pass the inspection once I turned it in. :?: Can someone please please please help me. I am second guessing doing this whole narration thing, but have literally spend probably 10 hours trying to get this book completed. Any help is so much appreciated!

I have attached a snippet of what I see in audacity when I run the ACX check.
Attachments
Capture.PNG
Capture.PNG (11.82 KiB) Viewed 328 times

kozikowski
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Joined: Thu Aug 02, 2007 5:57 pm
Operating System: OS X 10.9 Mavericks

Re: Noise Floor

Post by kozikowski » Wed Sep 05, 2018 3:27 am

Do you see the third reading down where it says noise is -233dB? That's impossible. Did one of the YouTube videos tell you to Generate Silence in your reading so you pass ACX? That's not a real background noise reading. The background noise in your performance is supposed to be measured by making a normal recording and then stop moving and hold your breath for two or three seconds. That will then record the sounds your actual room is making, called "Room Tone."

Guaranteed it's not going to come in at -233dB. Much more likely -40dB to -70dB.

And yes, people fail this all the time because most people's houses are terrifically noisy and we just get used to it.

ACX Check is easy to fake out because it blindly searches for the quietest part of the show and measures that. It has no idea -233dB is not a rational number.


Do you have a good backup of your reading? The rule is be able to point to two separate places that contain your show. That's so you have a safety copy when the dog eats your laptop. Did you use Audacity Projects to save your work? If all the projects still open, File > Export all the chapters one at a time as WAV (Microsoft) 16-bit sound files. You can get into trouble with Audacity Projects.


Do a test recording and post it on the forum. This is the format. Do Not add effects or filters. Just read it, stop, export as WAV and post it. Content isn't important. Read the milk carton.

http://www.kozco.com/tech/audacity/Test ... _Clip.html

Koz

kozikowski
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Posts: 41531
Joined: Thu Aug 02, 2007 5:57 pm
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Re: Noise Floor

Post by kozikowski » Wed Sep 05, 2018 3:31 am

I would not be shocked if ACX Quality Control looks for irrational numbers like that and manually and very carefully measures noise rather than relying on the automation.
It stated the requirement is a maximum of -60db noise floor.
Yes, that's the specification, but what exactly did they say?

Koz

christianw
Posts: 11
Joined: Sat Jul 21, 2018 11:30 pm
Operating System: Windows 10

Re: Noise Floor

Post by christianw » Wed Sep 05, 2018 3:39 am

As a beginner you might be interested in a my basic introduction to ACX reality:

https://vimeo.com/287374350

BrittanyS
Posts: 29
Joined: Wed Sep 05, 2018 2:09 am
Operating System: Windows 10

Re: Noise Floor

Post by BrittanyS » Wed Sep 05, 2018 9:58 pm

Here is a sample of one of my clips. I will do just about anything not to have to record all of this audio again- literally hours and hours of recording :cry:

kozikowski wrote:
Wed Sep 05, 2018 3:27 am
Do you see the third reading down where it says noise is -233dB? That's impossible. Did one of the YouTube videos tell you to Generate Silence in your reading so you pass ACX? That's not a real background noise reading. The background noise in your performance is supposed to be measured by making a normal recording and then stop moving and hold your breath for two or three seconds. That will then record the sounds your actual room is making, called "Room Tone."

Guaranteed it's not going to come in at -233dB. Much more likely -40dB to -70dB.

And yes, people fail this all the time because most people's houses are terrifically noisy and we just get used to it.

ACX Check is easy to fake out because it blindly searches for the quietest part of the show and measures that. It has no idea -233dB is not a rational number.


Do you have a good backup of your reading? The rule is be able to point to two separate places that contain your show. That's so you have a safety copy when the dog eats your laptop. Did you use Audacity Projects to save your work? If all the projects still open, File > Export all the chapters one at a time as WAV (Microsoft) 16-bit sound files. You can get into trouble with Audacity Projects.


Do a test recording and post it on the forum. This is the format. Do Not add effects or filters. Just read it, stop, export as WAV and post it. Content isn't important. Read the milk carton.

http://www.kozco.com/tech/audacity/Test ... _Clip.html

Koz
Attachments
Sample.aup
Here is a sample
(2.65 KiB) Downloaded 9 times

kozikowski
Forum Staff
Posts: 41531
Joined: Thu Aug 02, 2007 5:57 pm
Operating System: OS X 10.9 Mavericks

Re: Noise Floor

Post by kozikowski » Wed Sep 05, 2018 10:18 pm

An AUP is not a sound file. It's the Audacity Project manager text file. This is one of the problems you can have with Audacity Projects.

Do a 20 second reading as you have been doing according to that simple format. File > Export > Export as WAV. The panel defaults to 16-bit Microsoft like this.


Screen Shot 2018-09-05 at 15.14.14.png
Screen Shot 2018-09-05 at 15.14.14.png (13.85 KiB) Viewed 307 times

Click Save, and post it here.

Koz

kozikowski
Forum Staff
Posts: 41531
Joined: Thu Aug 02, 2007 5:57 pm
Operating System: OS X 10.9 Mavericks

Re: Noise Floor

Post by kozikowski » Wed Sep 05, 2018 10:29 pm

@christianw

I'm surprised you got Noise Gate to work. That's not a particularly well-behaved tool and worse, if you do anything wrong, ACX can hear artifacts. They hate processing artifacts.

Koz

BrittanyS
Posts: 29
Joined: Wed Sep 05, 2018 2:09 am
Operating System: Windows 10

Re: Noise Floor

Post by BrittanyS » Thu Sep 06, 2018 2:35 am

Here you go. Seriously, thank you so much for your help.

Could it be because I clicked "Generate" and then "silence" to get my 1 second of silence at the beginning and end of the clips?



kozikowski wrote:
Wed Sep 05, 2018 10:18 pm
An AUP is not a sound file. It's the Audacity Project manager text file. This is one of the problems you can have with Audacity Projects.

Do a 20 second reading as you have been doing according to that simple format. File > Export > Export as WAV. The panel defaults to 16-bit Microsoft like this.



Screen Shot 2018-09-05 at 15.14.14.png


Click Save, and post it here.

Koz
Attachments
Sample.wav
(1.2 MiB) Downloaded 13 times

BrittanyS
Posts: 29
Joined: Wed Sep 05, 2018 2:09 am
Operating System: Windows 10

Re: Noise Floor

Post by BrittanyS » Thu Sep 06, 2018 2:51 am

Also, here is a sample of an entirely unedited clip.



kozikowski wrote:
Wed Sep 05, 2018 10:18 pm
An AUP is not a sound file. It's the Audacity Project manager text file. This is one of the problems you can have with Audacity Projects.

Do a 20 second reading as you have been doing according to that simple format. File > Export > Export as WAV. The panel defaults to 16-bit Microsoft like this.



Screen Shot 2018-09-05 at 15.14.14.png


Click Save, and post it here.

Koz
Attachments
Blank Testing Sample.wav
(1.93 MiB) Downloaded 12 times

BrittanyS
Posts: 29
Joined: Wed Sep 05, 2018 2:09 am
Operating System: Windows 10

Re: Noise Floor

Post by BrittanyS » Thu Sep 06, 2018 3:05 am

Clearly I have no idea what I am doing :lol:

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