How to approach normalizing my audio clips?

It seems to me that some of my audio is much louder than other audio, for example music versus some select sound effects. I know I can adjust the volume on individual sound sources, but in some cases a single sound source may be playing different clips in different situations, so I’d prefer to normalize clip volumes on or before import so I don’t have to fiddle with audio source settings depending on clips being played at the time.

Is there a recommended approach for normalizing volume for all audio files used in a project? I don’t trust myself to do it by ear, so I’d want some tool-assisted option if there is one.

It is better to do it by hearing and keeping an eye on the waveform and dB meter. Waveform helps any immediate clipping points. dB meter helps especially if you mix different waves.

I suggest adjusting your levels in a way that loudest one doesn’t hit more than -3dB. Lower that threshold if many sounds overlap in your game. Their total should never hit 0dB or there will be clipping distortion.

Unfortunately a sound clip that is not that much loud can easily hit -3dB if it involves too much bass frequencies. In a similar way you can get a very disturbing -20dB high frequency sound. Also human hearing sensitivity varies across the frequency spectrum. So better to do it while hearing and seeing before the import.

Normalizing only sets the peak point of each wave to the same dB level which has nothing to do with how loud is that sound.

I see from comments and answers that this is more complicated than I understand. However my problem was satisfactorily solved when I loaded all of my clips into Audacity simultaneously, ‘normalize’-d them, then re-exported them to overwrite the original files.

So for anyone facing this problem, I recommend starting there and then referring to other comments in this thread for where to go next if you need to dig deeper.

I just did a round of this, and in short here were my findings:

  • Download and install Audacity
  • Create a “Chain” to Normalize your sounds to -9dB.
  • Use that “Chain” to normalize all your sound effects to -9dB

The reason I chose -9dB instead of -6dB, or -3dB for our game is that we’ll have a lot of sound effects running at the same time as it’s a synchronous multiplayer game, and so when you add up a bunch of sound effects it can still be loud. But really what’s important is the normalization part. You should also normalize your music the same way.

bererton +1 - Master your audio at -9db is a good start point (3 of such will sum-up at 0 db)
the right way is to mix your sound-set in an audio project and master the MASTER-BUSS
at -1db Peak level if you want your game to compete with commercials, -3db for high but safe Volume. -6db for smooth mastering (still pretty high) or -9db would be the sweet-spot when you **mix your sounds properly ** and take care of the average/long term volume measured by lufs. -9 Lufs Average is the volume of a CD ALBUM MASTER or -14 lufs Average is the MAX level on spotify & youtube. now you have a better idea on whats happening (volume-wise) on the different platforms, and you can take a better decision about the overall volume you want to maintain, and the maximum peak level to keep your game powerful but on the safe side and far from clipping.