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Re: ACX Dang that noise floor

Posted: Thu Jan 09, 2020 7:14 pm
by fredericamg
Koz: Lauren Bacall, LOL. I wish I could cultivate it, like an actor cultivates exactly 2 days' worth of chin stubble.

Didn't they get Andy Williams to dub a song for her? I forget which movie.

Yes, I can easily put these files into my Dropbox and send you a link. Would you be able to take a look at them and see whether they are salvageable? That is my first hope.

(How should I send you the link? Email? Text? Just paste it in here?)

If I have to re-record--sigh, it can be done. My vocal weakness is that, often enough, after an hour or so of reading I get a frog in my throat that won't go away. (Only when recording, not when giving a speech. Go figure.) But if I have to record one hour a day for 9 days, it's not impossible.

On my mental calendar: our Lent begins March 1, and the book is designed to be read for the 40 days of Lent (40 short chapters), so it would be great if it could be available before that. Which is why I sent it to ACX on December 3. :-(

If seeing ACX comments is useful to you, I'll paste in below the review letter I got from ACX earlier this year, when I sent in the files in February (and missed last year's Lent). However I no longer have the files that this letter is based on, since I re-saved my recent edits under the same file names.

So here's ACX's review of the submission last February:

[You'll notice that the noise floor evaluation says it applies to "all" of the files, but the RMS evaluation applies to "17 files." They attached a "graph" showing which files. I opened it. It was not a graph, but a simple Courier-font list--of all the files. ]

<<Hello,

The ACX Quality Assurance Team has reviewed your recently-completed audiobook, "The First Fruits of Prayer: A Forty-Day Journal through the Canon of St. Andrew ". We have found 2 issues that must be corrected before we are able to process your audiobook for retail sale.

Below, we have listed the requirements not met, the files affected, and our recommended solutions:

Issue: All files contain excessive background/ambient noise and do not meet our noise floor requirement. Please revise all files.

Requirement: a maximum -60dB noise floor

Solution: In post-production, you may use noise gating or reduction to help reduce the noise floor. Please be mindful that incorrect use of this kind of software can lead to poor sound audio. The best way to go about lowering your noise floor is to identify and eliminate the source of the noise. Often it could be the microphone picking up a loud sound from within the room or it could be a gain staging Issue with your recording equipment. Please be sure that any noise emanating appliances (air conditioner, computer fan, fluorescent lights, etc.) are turned off or isolated so the microphone does not pick up the sound. Our recent ACXU seminar Studio Gear Series goes over the importance of sound proofing your recording area. The Mastering topic in our Video Lessons & Resource section contains samples of what a noise floor should sound like.

Issue: 17 files have a low RMS and are too quiet: Please see attached document for a graph of affected files.

Requirement: files measuring between -23dB and -18dB RMS

Solution: Please raise the overall RMS level of each file to within our requirement. For example, if a file's RMS is -30dB RMS, it must be raised +8dB to be within our -18dB to -23dB RMS requirement range. Learn Mastering with Alex the Audio Scientist.

After you have corrected the issue(s) above, follow these steps to submit the project for review:

Log into your ACX account, navigate to the In Production tab, and select Title from your list of projects.
Select "Edit" next to the files listed above to delete, replace, and upload corrected .mp3 files.
Confirm the files appear in the order they are intended to be heard.
Click "I'm Done".

Please be aware that the ACX QA review is not an end to end review of your production and you should always do a full edit, QC, and mastering pass before submission. This is important because errors in the audiobook could garner negative reviews on Audible, Amazon, or iTunes which could result in fewer sales.>>

Re: ACX Dang that noise floor

Posted: Thu Jan 09, 2020 8:31 pm
by kozikowski
an actor cultivates exactly 2 days' worth of chin stubble.
That's not the hard part. The hard part is maintaining that growth through five days of shooting. Makeup gets a warning if you're planning on shooting out of order. Today, we're going to shoot the establishing scenes from the beginning of the show.

I'm not sure where to go with this. We don't know what Maryland Pro did to your first six books and we can't take them apart to find out. That's why we insist that you post uncorrected, clean work for inspection on the forum.

I suspect we can master what you did to passing for submission, but there's little chance they're going to match the older work. That's going to come up. That's their phrase "... you should always do a full edit, QC, and mastering pass." Everything needs to match.

I need to drop for a while.

Koz

Re: ACX Dang that noise floor

Posted: Thu Jan 09, 2020 10:53 pm
by fredericamg
Koz: Oh, so that's why you went to California!

Thanks, everyone, for all your help.

Re: ACX Dang that noise floor

Posted: Fri Jan 10, 2020 1:32 am
by kozikowski
that's why you went to California!
I took a wrong turn in Arizona. Wait. What is this warm place with palm trees and surfers?

I'm sending you high quality MP3s of your test clips. I used the classic DeEsser...

viewtopic.php?p=245549#p245549

...according to these settings.


Screen Shot 2020-01-09 at 17.14.06.png
Screen Shot 2020-01-09 at 17.14.06.png (48.51 KiB) Viewed 961 times

I used the mastering tools like this.



Screen Shot 2020-01-09 at 17.25.48.png
Screen Shot 2020-01-09 at 17.25.48.png (30.04 KiB) Viewed 961 times
From here.

https://wiki.audacityteam.org/wiki/Audiobook_Mastering

The two states are different. Only Tennessee needs the DeEsser.

Here's how mastering goes.

====================

Maryland/Tennessee Matching
2019-01-09


FF MD
---------
Audiobook Mastering
Effect > Noise Reduction 9, 6, 6


FF TN
---------
Audiobook Mastering
Effect > DeEsser -20.0, 10.0, 2500.0, 8000.0, 10, 5.0
Effect > Noise Reduction 9, 6, 6

======================

The two groups more or less match with TN being slightly more noisy than MD. Both pass. We hope nobody will notice. You can't just crank up the Noise Reduction because that may affect your voice.

Koz

Re: ACX Dang that noise floor

Posted: Fri Jan 10, 2020 3:05 am
by kozikowski
I don't remember, have you ever used Noise Reduction? It works in two swipes.

Drag-select some portion of clean background noise. Quarter Second? Half Second? No shuffling, breathing, coughing, etc. Just background sound.

Effect > Noise Reduction > Profile.

That lets Noise Reduction "sniff" the noise like a good dog.

Then you select the whole track and Effect > Noise Reduction: 9, 6, 6 > OK.

That's the actual reduction part. Gentle Noise Reduction is considered 6, 6, 6, noise reduction of the beast. You need a little more of a push than that so 9, 6, 6 is stiffer reduction. If you go too high, the noise will go down, but your voice will start to sound like you're talking into a wine glass.

I posted the abbreviated version of Mastering in yellow highlight. If you look at the exhaustive writeup instead, it will tell you how to get the tools you don't already have.

So yes, if that's close enough for ACX, you can mix MD and TN readings. Quick word, if you can't restrain yourself and want to apply additional filters and corrections, you will have to apply them to all the chapters and make sure they don't conflict with the unique Tennessee settings.

Koz

Re: ACX Dang that noise floor

Posted: Fri Jan 10, 2020 9:01 am
by kozikowski
You weren't expecting a one-button-push solution were you?

This is less terrible than it looks because many of the tools hold their settings. For example, if you set up Effect > Limiter once, the second time, it's Effect > Limiter > OK. I can whip through Mastering a short test in about 12 seconds. DeEsser holds its settings, too, but not so Noise Reduction. If you close Audacity anywhere in the process, Noise Reduction's eyes will roll up and it will forget its profile.

There is a one-button Mastering published. but I'm not fond of it because the first step, Effect > Filter Curve is not unconditionally stable. You won't know if it gets it wrong—it will just start producing bad chapters.

There is an up side. If all the chapters are of that quality, this is one known process to make them pass.

Koz

Re: ACX Dang that noise floor

Posted: Fri Jan 10, 2020 9:17 am
by kozikowski
You were never exposed to the full glory of Mastering and voice corrections. Now you know why we strongly recommend a well-behaved microphone and studio. With my Zoom H1n or your H2, it's possible to record in a dead quiet, echo free room, transfer it to the computer, cut it down, master it and submit it.

No other corrections.

Go make coffee.

Koz

Re: ACX Dang that noise floor

Posted: Fri Jan 10, 2020 10:02 am
by Trebor
fredericamg wrote:
Thu Jan 09, 2020 4:35 pm
Trebor, thanks for producing that comparison of "laryngitis". I have never used De-Ess or De-Click. I see "click removal" in my Audacity 2.3.3, but not De-Ess. That's a plug-in, right?
Yes, you can get a DeClicker plugin specifically for Audacity here ... viewtopic.php?t=79278
( Some store-bought DeClicker plugins work in Audacity, they are simpler to use & faster, but co$t).

fredericamg wrote:
Thu Jan 09, 2020 4:35 pm
I am wary of tinkering with Dynamics. This sounds good, sounds bigger.
But I'm not sure I should apply it like wallpaper over 9 hours of audio--
I used the louder end of the ACX specifications for both RMS & peak.
For the the best signal-to-noise ratio for the consumer, the RMS volume should be close to the loudest permissible value.
Could maintain RMS near maximum permitted, but reduce the peak from -3dB to -6dB if you prefer less dynamic-range ...
-3db peak then -6dB peak , (both -18dB RMS).flac
The -3dB waveform is closer to the dynamic-range of popular audio books
(768.39 KiB) Downloaded 5 times

Re: ACX Dang that noise floor

Posted: Fri Jan 10, 2020 7:21 pm
by fredericamg
Wonderful, thanks so much. Now I know what to do. I lean toward doing the least tinkering possible, but it was helpful to know that you can't have perfect ACX Noise Floor and RMS right from the raw take. It will always need a little help.

I have my work cut out for me this weekend--2 Introductions, 40 short chapters, and 3 Appendices. But at least I know what to do! Thanks so much for showing me the way out of the thicket. I'll be back after I've done some work on it (and if I run into anything confusing).

--F

Re: ACX Dang that noise floor

Posted: Fri Jan 10, 2020 8:33 pm
by kozikowski
It should all be confusing. There are only three people on earth trying to match two different studios.

Koz