Audio between levels transition

I have a game where the music continues until you succeeded the level and loops, even if it restarts, works great.
However, I have a similiiar tracks between levels, and i would like the track to change only when he succeeded the level and the previous track ended, so it will have a fluent effect.
I guess what i am asking for is how to code the “change when done” command, and I will add it to my “if” condition.

Something like this?

public AudioSource audio1;
public AudioSource audio2;

bool succeededTheLevel;

void Update()
    //Call when the scene changed
    SceneManager.activeSceneChanged += activeSceneChanged;

    //True when the scene changes and audio 1 stops
    if(succeededTheLevel && !audio1.isPlaying)
        //Break the loop if the second audio is already playing
        if (audio2.isPlaying)


void activeSceneChanged(Scene arg0, Scene arg1)
    succeededTheLevel = true;