

Since you are referring to "how loud they sound (subjectively)", we will use "LUF" measurement rather than "peak". I'll refer to them as "foreground" and "background". You will need two audio tracks in the Audacity project. Rephrasing this question: "How do I make the speech recording 20 dB below the foreground?"

Ok now how would I make the music ie the foreground 20 decibels above the subliminal affirmations which should barely be able to be heard if the foreground is 20 decibels above the hidden subliminal affirmations that being the case at what decibels should the affirmations be and how would I accomplish this Nature doesn't lend itself to precise engineering measurements. The Spring Rain In The Trees / Ocean Crashing is going to be constantly moving. The best you're going to do is approximately 37-ish. Human speech in free air.Īlso, you're never going to hit 37.52dB-SPL. Then play the mixture for the actual show.Īlso, as above, my meter will not do this because the quietest it will measure is 60dB SPL. I would probably make a test with five seconds of just music and then five seconds of just message to make sure the difference in volume has been preserved. When you play the file to the subject/patient, use the sound meter to set the player volume so the music or foreground sound presents at 37.52 dB-SPL and the message should arrive 20dB quieter than that.

The waves on the timeline should almost vanish.Įxport to the file of your choice and Audacity will mix the two tracks. This number would be the desired difference between the foreground and background volumes. Then select the message and Effect > Amplify > Amplification -20 (top number) > OK. Then produce the message in the next track down at that same volume and duplicate it as above in this message thread. That should give you a good recording with no overloads (too loud) or background noise (too quiet) problems. Record or produce the masking/foreground sound so the peaks on the Audacity recording meter tip up into the -6dB to -10dB range. I doubt you could make a good recording of a 17dB SPL performance.

Actually, the Sound Pressure meter would be used to make sure the recording is being played to the subject/patient properly.
