How to set RMS on recorded chapters
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sonrisajones
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How to set RMS on recorded chapters
Hello dear forum - I have recorded all the chapters of my book, using latest Audacity, etc. When I check RMS level (peak level and noise floor is fine) I get a message saying decibels are -24.5 instead of -23.5. My question is - how do I reset the RMS on recorded files? Thank you so much. Be safe.
Linda
Linda
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kozikowski
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Re: How to set RMS on recorded chapters
You can use RMS Normalize. It has to be installed.
viewtopic.php?p=325078#p325078
But.
Are you planning on submitting to ACX/Audible? Did you post a test to see if everything was OK before you read the whole book? Or is that message from ACX?
Audacity has an Audiobook Mastering suite of tools that guarantee Peak and RMS and if you read well in a quiet, echo-free room, Noise should fall in and that's all you need.
I need to change machines.
Koz
viewtopic.php?p=325078#p325078
But.
Are you planning on submitting to ACX/Audible? Did you post a test to see if everything was OK before you read the whole book? Or is that message from ACX?
Audacity has an Audiobook Mastering suite of tools that guarantee Peak and RMS and if you read well in a quiet, echo-free room, Noise should fall in and that's all you need.
I need to change machines.
Koz
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kozikowski
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- Operating System: macOS 10.13 High Sierra
Re: How to set RMS on recorded chapters
Before you start any surgery, do you have backup copies of your raw readings and edit masters? That's highly recommended given how far into the process you are. Either save Audacity Lossless Projects, or Export WAV (Microsoft) 16-bit sound files. Copy them to separate storage such as external drives, thumb drives, or cloud storage.
It's totally possible to fix one technical standard and mess up the others.
We produced the Audiobook Mastering Suite.
That's from here.
https://wiki.audacityteam.org/wiki/Audiobook_Mastering
Always apply all three tools to every chapter or section. ACX Check is very similar to the ACX automated robot. It will tell you if all three of your technical standards have been met, and by how much.

Of course in the case of ACX, you also have to pass Human Quality Control which listens for reading errors and sound quality.
As a fuzzy rule, you should clear Noise by at least -65dB, not just -60dB which is the actual standard.
Did everything come out OK?
Koz
It's totally possible to fix one technical standard and mess up the others.
We produced the Audiobook Mastering Suite.
That's from here.
https://wiki.audacityteam.org/wiki/Audiobook_Mastering
Always apply all three tools to every chapter or section. ACX Check is very similar to the ACX automated robot. It will tell you if all three of your technical standards have been met, and by how much.

Of course in the case of ACX, you also have to pass Human Quality Control which listens for reading errors and sound quality.
As a fuzzy rule, you should clear Noise by at least -65dB, not just -60dB which is the actual standard.
Did everything come out OK?
Koz
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sonrisajones
- Posts: 20
- Joined: Thu Apr 23, 2020 7:50 pm
- Operating System: macOS 10.13 High Sierra
Re: How to set RMS on recorded chapters
Thank you and sorry for the delay in responding - what a ride this recording project has been!
Yes, these tools helped enormously, but I still didn't pass ACX QA - (extraneous sounds and incorrect spacing at beginning and end of clips) I have created a better space to record in and have figured out how to use room tone in the editing process so fingers crossed for my next pass with them.
Still curious about the noise reduction tool - if I follow the sequence audacity created for Audible, I shouldn't need to use it, right? BTW this process (filter, rms normalize, limiter) is quite elegant and worked every time to pass the ACX check.
Thank you again,
Linda
Yes, these tools helped enormously, but I still didn't pass ACX QA - (extraneous sounds and incorrect spacing at beginning and end of clips) I have created a better space to record in and have figured out how to use room tone in the editing process so fingers crossed for my next pass with them.
Still curious about the noise reduction tool - if I follow the sequence audacity created for Audible, I shouldn't need to use it, right? BTW this process (filter, rms normalize, limiter) is quite elegant and worked every time to pass the ACX check.
Thank you again,
Linda
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kozikowski
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Re: How to set RMS on recorded chapters
Close. Audiobook Mastering guarantees Peak and RMS (Loudness). You can put floor sweepings in there and pass those two. But you may not pass noise. Noise is very troublesome. Anyone who has struggled with background noise now knows why commercial soundproof studios exist.this process (filter, rms normalize, limiter) is quite elegant and worked every time to pass the ACX check.
I have a very quiet bedroom and can push out a technically perfect voice performance any time I want...as long as I miss the Metrobus going by and the trash collection people on Monday. I recently published a file of what it sounds like when Southern California Gas decides to put a new gas trunk line under the street.
I am a little surprised people regularly get stuck with that. ACX is pretty clear they want.(incorrect spacing at beginning and end of clips)
No refrigerators turning on or dogs barking. Those are Noise.extraneous sounds
How did you do it? There's tricks to it. Yes, it's totally possible to use egg cartons inside a large cardboard box as your sound studio, but you have to use cardboard egg cartons, not plastic foam.I have created a better space to record in
I published a kitchen table sound studio from furniture moving blankets and plastic pipes, which, if you're close to a Home Depot, come pre-cut.
viewtopic.php?p=369938#p369938
Noise Reduction used to be called Noise Removal. Too many people were expecting it to remove all the noise from their trashy performance...to zero. Neither one will do that.Still curious about the noise reduction tool
Noise Reduction is a siren song luring your ship on to the rocks (Greek mythology). There's the philosophic problem of starting your career planning for disaster rescue. You should think about possible sound damage, but not intentionally taking shortcuts because you can always "fix it in post production."
Kiss of death.
If you can pass noise by -65dB or quieter naturally, you can ignore Noise Reduction. -60dB is the limit.
viewtopic.php?p=384351#p384351
That's assuming nice, well-behaved, stable, constant noise such as microphone hiss or far background air conditioning noise. It won't do anything for noises that change over time (trucks going by) or certain digital noises that sound like ice picks in the ear. Those will not be tolerated even if they are quieter than -65dB.
So it's down to seeing how you do. You can also publish a very short sound test here and we will comment. You don't need the Catskill cows if you have a good speech you like. Do Not use "testing one two three." A passage from Sponge Bob Square Pants might be nice.
https://www.kozco.com/tech/audacity/Tes ... _Clip.html
Koz
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kozikowski
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Re: How to set RMS on recorded chapters
If your ACX-Check looks like this.

Then you have the old one. There is a new, faster version with a shorter response panel. If you're using Audacity 2.4.1, the older version may stop working.
https://wiki.audacityteam.org/wiki/Nyqu ... #ACX_Check
Koz

Then you have the old one. There is a new, faster version with a shorter response panel. If you're using Audacity 2.4.1, the older version may stop working.
https://wiki.audacityteam.org/wiki/Nyqu ... #ACX_Check
Koz
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sonrisajones
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- Joined: Thu Apr 23, 2020 7:50 pm
- Operating System: macOS 10.13 High Sierra
Re: How to set RMS on recorded chapters
thank you so much ! Here's a clip that passed ACX - I have a very quiet space (I live in a rural area, no traffic) and now I have have blanketed corner of my closet - I hit the correct noise floor with ACX. What I've found is that the other tools - filter - rms normalize - limiter seem to work better with noise reduction in play - but perhaps that's wrong -
how do I upload a clip?
how do I upload a clip?
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sonrisajones
- Posts: 20
- Joined: Thu Apr 23, 2020 7:50 pm
- Operating System: macOS 10.13 High Sierra
Re: How to set RMS on recorded chapters
I use RMS normalize, downloaded the plug in - should I download Audacity 2.4.1 please? would that be a good idea or not necessary? thank you so much for your help...
Linda
Linda
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sonrisajones
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Re: How to set RMS on recorded chapters
OK, here is a clip in the format you requested. Thank you for your time and expertise.
Linda
Linda
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kozikowski
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Re: How to set RMS on recorded chapters
Extra points if you can read that all in one breath. [gasp] Catskill Farms.....
I got the file to pass Audiobook standards, but it took a little effort to get there. It should sound exactly like you except very slightly louder and passing audiobook standards.
First I used the Audiobook Mastering Suite as published.
You still have a little house power hum in the show and I used a Hum Remover tool to get rid of it. You're in the US, right? It's US kind of hum.
That left you passing technical standards—but just barely. So I added a very gentle noise reduction
This is the newer ACX Check.
This is the mastered file. Peaks are quieter than -3dB, RMS (loudness) is between -18dB and -23dB, and noise is quieter than -60dB.
These are the settings for Hum Removal.
And these are Noise Removal settings
It's 6, 6, 6, so I call it Noise Reduction of the Beast.
Do you remember turning your head as you were reading at about the 6 second mark? There is a noticeable drop in volume right there. You can't do that while reading for a bunch of different reasons. It sounds a little funny (like you lost your place) and it's very difficult to fix. You can add processing tools to help, but they can throw the other tools and corrections off. You start chasing your tail.
We can try to find out where that hum is coming from or we can just go with the hum removal tool. My personal preference is to use a few tools as possible. You only have to fix the hum noise once, but you have to remember to remove it, every time, in every file, forever.
Let us know which direction you want to go and I'll fill in the blanks. I'm going to go look at your other sound file.
Koz
I got the file to pass Audiobook standards, but it took a little effort to get there. It should sound exactly like you except very slightly louder and passing audiobook standards.
First I used the Audiobook Mastering Suite as published.
You still have a little house power hum in the show and I used a Hum Remover tool to get rid of it. You're in the US, right? It's US kind of hum.
That left you passing technical standards—but just barely. So I added a very gentle noise reduction
This is the newer ACX Check.
This is the mastered file. Peaks are quieter than -3dB, RMS (loudness) is between -18dB and -23dB, and noise is quieter than -60dB.
These are the settings for Hum Removal.
And these are Noise Removal settings
It's 6, 6, 6, so I call it Noise Reduction of the Beast.
Do you remember turning your head as you were reading at about the 6 second mark? There is a noticeable drop in volume right there. You can't do that while reading for a bunch of different reasons. It sounds a little funny (like you lost your place) and it's very difficult to fix. You can add processing tools to help, but they can throw the other tools and corrections off. You start chasing your tail.
We can try to find out where that hum is coming from or we can just go with the hum removal tool. My personal preference is to use a few tools as possible. You only have to fix the hum noise once, but you have to remember to remove it, every time, in every file, forever.
Let us know which direction you want to go and I'll fill in the blanks. I'm going to go look at your other sound file.
Koz