Audacity Forum

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... Here are the ACX requirements. 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 Recommended Audiobook Mastering Process 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.