Effects are not applying on long recordings

My system: Dell Inspiron 3668/Windows 10 pro/Core i7/16g of RAM

When I record short clips of audio (5 to about 12 minutes), and apply effects (EQ, Compressor, Normalize) the effects apply with no problem. However, when recording an audio clip of about 25 to 35 minutes, the effects will not apply. Does anyone know why this could be happening or what I’m doing wrong? Thanks for the the help.

Which three-number Audacity do you have?

I can give you a bad guess. When you do an effect, Audacity has to create an UNDO and it does it by making an exact copy of the “before” sound. The show doubles in size. If you start to run out of drive space, Audacity will not be able to do that and it be worse for longer passages.

How much space do you have?

I don’t think this is the actual problem, but it fits the symptoms well.


the effects will not apply.

You say that as if they were one thing. Do you have the three different effects set up in Chain or Batch so they run all at once? What happens when you apply them individually? Does it die at the first one? Is there an error message or sound effect warning?


Thanks for the replies.

I’m using Audacity 2.2.1
I have 931 GB of storage on my HD

My sequence of effect application is: EQ/compression/Normalize. One at a time

The EQ effect is applying correctly for the entire (35 minute recording).
When I preview the Compressor effect for the entire recording, I can hear the change. But, when I click OK it does not apply the effect. When previewing, the sound level is running from -3 to 0 db. When I click OK it drops down to about -12 to -9 db.

If, however, I select a portion of the recording and apply compression, it does so with out a problem.

Does Normalize work OK?

So this probably has nothing to do with Chains and so far it’s only Compressor and Compressor Preview.


The Normalize effect isn’t doing much if anything. I don’t see the wavelength change at all.
As far as when I apply the EQ, I hear a difference but the wavelength doesn’t expand like it does when I apply it to a shorter portion of the recording. The compressor effect sounds great when I click on the Preview button. But when I click on the OK button and it finishes “applying” it does nothing and in fact the db level goes down.

I tried splitting the recording in half and applying compression to half the recording and I had the same result. I did the same with about 7 minutes of the recording and everything work good. All the effects were applied correctly. And, the end db level was between -3 and 0

I failed to mention something that might or might not be relevant.

I used to record my podcast on a separate multi-tracker. Then, I would import the wave file from the player, edited and would apply the effects with no problem. Of course that was using an older version of Audacity. For the last couple of weeks I have been recording straight into my computer from my Behringer 1202usb mixer.

It’s good to know that Normalize, Amplify and a selection of other tools work on wave peaks, not loudness or other measurement. So if you have one extreme loudness peak anywhere in the show, Normalize is going to normalize that one peak and to heck with the rest of the show.

It’s also good to know that in spite of the fancy-pants name, Normalize just changes the volume similar to turn up the volume on a radio once at the beginning of an hour show. It doesn’t even out volume variations, compress volume differences or any other variation. Normalize and Amplify are sisters. The only difference is the way you tell them to change the volume.

Effect > Amplify on the whole track. Don’t OK it. Read the numbers. If your numbers top to bottom are (for example) 3 and 0, that means something somewhere in your show is “hot,” within 3dB of overload (0). It doesn’t matter if the rest of the performance is low volume and very quiet.

So your job is to find that one peak. Effect > Amplify > OK. View > Show Clipping. That will give you red marks on the timeline any time a sound wave hits maximum. Scan through the show looking for that one red mark.


I wonder if your separate recorder automatically leveled out your extreme sounds, so the show was one third finished before it ever left the recorder. A presentation like that would sail straight through post production processing.

You might be a client for RMS Normalize. That one ignores peaks in favor of paying attention to loudness. It was designed for the audiobook people.


That will intentionally create peak damage and depends on following it with Limiter to suppress crunchy overload problems.


Thanks for all the advice guys. Really appreciate it. I will try all and see if I can get it to work.