Again, for ACX they say the RMS I’m using is too low and needs to be at 3.7db … how do I adjust that ?
Again, for ACX they say the RMS I’m using is too low and needs to be at 3.7db
Something is wrong… [u]Here are the ACX requirements[/u]. The RMS level must be between -23 and -18dB. The peaks should not exceed -3dB.
how do I adjust that ?
The RMS Normalize effect will accurately set the RMS level. (RMS is a kind of “average” which correlates with perceived loudness. Then typically the peaks will be too high so you’ll need to use the Limiter effect to get the peaks in spec.
The [u]Recommended Audiobook Mastering Process[/u] will get the levels into spec. You may need some additional work to meet the noise specs.
ACX said my RMS was too low … and that I need to raise the level of this file 3.7db. So … how do I do that?
If it needs to be increased by 3.7dB you can simply use the Amplify effect set to +3.7dB. (Or, just follow the recommended procedure and run RMS Normalize set to -20dB. 
)
Then, run ACX Check to make sure the peak level and noise level are also in spec.
…When you amplify but 3.5dB, the peak level and noise level will also increase by 3.5dB.
Sorry for being so technically bummed … but I still don’t understand (but getting close).
In the note from ACX, they indicated my current RMS was -26.7 (too low)and needed to be raised 3.7db … so, if I raise it BY 3.7db, would that not make the new RMS number a -23???
Now, if their grammar was bad and it needed to be upgraded TO +3.7. that grays out the OK button because of clipping.
Or … do they mean to set it at -3.7db
As you can see, I’m confused and can you help ? Is their an optimum setting that I should be using for a mono-recording?
Zero is maximum loudness and it gets quieter as the negative number gets larger.
Your background noise level should be -60dB or quieter (-65dB is good) and your voice should land between -18 dB (louder) and -23dB (quieter). -26dB is too quiet.
However it’s usually not a matter of boosting your volume because that can throw the other sound values off. We have a audiobook mastering process to help with this.
https://wiki.audacityteam.org/wiki/Audiobook_Mastering
Koz
In the note from ACX, they indicated my current RMS was -26.7 (too low)and needed to be raised 3.7db … so, if I raise it BY 3.7db, would that not make the new RMS number a -23???
Correct!!! And as above, that (just barely) meets their requirements of -18 to -12dB.
requirements of -18 to -12dB.
Or even -18dB to -23dB.
Caffeine deprivation.
Koz
The Audiobook Mastering process in that post guarantees Peak and RMS audiobook values. If you announce well in a quiet, echo-free room, you may be done.
Koz
Thanx, Koz … last question is … can I, once finished, go back and apply this amplification across the entire sound track … or do I need to do this at the start? And do I just go to the amplify box and enter, for instance, -23 in the upper box?
I guess that’s 2 questions …
can I, once finished, go back and apply this amplification across the entire sound track … or do I need to do this at the start?
The whole file. Every file/chapter has to meet the specs. Most likely, each chapter will probably need a different adjustment…
And do I just go to the amplify box and enter, for instance, -23 in the upper box?
No! A negative value will give you attenuation instead of amplification and you’d end-up 23dB lower at -47dB. (Amplify “knows” the peak level so you can enter a new peak, but it knows nothing about RMS.)
But look - It’s a LOT easier to follow the recommended procedure and use RMS Normalize. RMS Normalize will analyze your file and adjust up or down as needed to hit the specified RMS target level.
Relax. Take a breath and take it slow… Carefully follow the whole procedure. The RMS level probably isn’t the only issue and you’re probably at the beginning of a long process.
… got 2 more related questions …
Y’all are great and thanx for the tip about RMS Normalize … but where do I find that?
I also understand that I would apply this at the end of recording session (Chapter 1, etc) and that each Chapter may be different and need ‘tweaking’. Soooo, a rather basic question (for me) is how, at the end of session, can I determine what the RMS was for the session … and thereby adjust accordingly. Or am I wayyyyyy off base ???
RMS Normalize and ACX check are optional add-on tools that have to be downloaded and installed. The Audiobook mastering link will give you links you to those and give you some instructions. After they are installed and enabled, RMS Normalize will show-up as an Effect and ACX Check will show-up under Analyze.
There is some more information on [u]this page[/u] about installing and enabling plug-ins.
Question #1: Trying to load the plug-ins you recommended but can’t seem to do it … instead of downloading a program, I get an English language fact sheet about the program. What am I doing wrong ?
Question #2: I used the Analyze section to determine the RMS of an entire sound track … for instance -30. How do I change that to, say perhaps -22, and then apply across the entire track?
This is my RMS Normalize plugin. I can’t find ACX Check right this second.
rms-normalize.ny (810 Bytes)
How do I change that to, say perhaps -22, and then apply across the entire track?
I think you’re working too hard. Audiobook Mastering was designed to correct a reading so Peak and RMS comfortably meet audiobook standards. If the tools aren’t needed, they don’t do anything. There is no tuning or adjusting. Just apply them all and in order.
It is possible to have a selection that’s too long. It will tell you that. ACX also has limits on how long your chapters can be.
There is no noise correction, the third audiobook standard.
This is where it gets interesting. Background noise can come from anywhere and some of it is easily cured, some of it has pre-baked tools to solve, and some of it you have to cure by changing your studio. If you start failing ACX Check because of noise and it’s not obvious why, you can post a sample of your work on the forum.
https://www.kozco.com/tech/audacity/TestClip/Record_A_Clip.html
Koz
Acx-check.ny (9.33 KB)
Koz
instead of downloading a program, I get an English language fact sheet about the program. What am I doing wrong ?
The two files you should have are:
“Acx-check.ny”
“rms-normalize.ny”
You don’t have to open & read those files but they do have English language “comments” for humans/programmers as well as the actual Nyquist-language computer code. (Any line that starts with a semicolon is a comment and it will be ignored by the computer.)
To install new LADSPA or Nyquist plug-ins, place them in Audacity’s Plug-Ins folder. On Windows computers, this is usually under > “Program Files/Audacity” on 32-bit Windows or “Program Files (x86)/Audacity” on 64-bit Windows.
… Open the > [u]Plug-in Manager[/u]> . > Select and enable > the plug-ins you added, then they will appear underneath the divider in the “Effect”, “Generate” or “Analyze” menus.
Question #2: I used the Analyze section to determine the RMS of an entire sound track … for instance -30. How do I change that to, say perhaps -22 and then apply across the entire track?
Simply run RMS Normalize and type in -22 (or -20 as recommended). It will automatically do it’s own analysis so you don’t have to analyze first.
If you run RMS Normalize and the Limiter the RMS and peak should both be in-spec (no analysis required). But, you still need to run ACX Check to check the noise floor.
If you’re reading and processing a long book, you should only have to put the correction values in each tool once. They’re sticky and will repeat until you change them.
Don’t leave out that Filter Curve tool. Many home microphones and microphone systems produce rumble and earthquake tones by accident. You can’t hear them, but they are sound and can throw off the other tools.
Koz
Thanx, Koz … lemme work on these issues … you’ve been more than helpful