Now you have explored the basics about how to open your ear and start training your perception and your ears to become more sensitive, you can apply the same material to getting used to the interval of a fourth, up and down, and then testing the difference between fourths and fifths using the audios.
There is a round of fourths with the notes, and then a training audio to try to get you to distinguish between fourths and fifths played melodically (one note at a time) and harmonically (both notes at the same time). To begin with, when you’re hearing them harmonically, you may find you are picking each note out and working out the interval between them in your head. This is fine to begin with, you’ll find that with time this will shift, and you begin to distinguish the different character of sound between the fifths and fourths.

Fourths training audio – do this first to learn to recognise fourths


Fourths review – improve your ability to tell the difference between fourths and fifths melodic intervals


Fourths Harmonic Intervals