Disguising the voice

I have recorded an argument between a male and female, however for its application within the mix I require the words to be unclear (avoiding any recognizable reason to be arguing).

Here is a sample of the original sound file: Couple Argument (Sample)
This sample was then processed through plug-ins available in Audacity. Extreme processing could have been applied however, it was important to keep the emotion delivered by both voices.

The first attempt was made through filtering techniques by only allowing the low frequencies to enter the mix. This first sample uses a low pass filter: Couple Argument (Sample) LPF 48dB Roll off 48dB and Cut off 1301.0Hz

This was furthered by the addition of a phaser: Couple Argument (Sample) LPF and Phaser

The final method was to use both a Low Pass Filter and a Vocoder which resulted in the blurring of words: Couple Argument (Sample) LPF and Vocoder

One of the issues with these methods was that the sound source includes both male and female voices, which have different frequencies.

Plenty more methods to try

To be continued!