1. How to change the key of accompaniment music or accompaniment of a song? After some searching, I found an excellent digital music editor and MP3 production software - Cool Edit Pro (you can also use Adobe Audition), which has good effects on processing rising and falling tones.

2. Download the audio editing app on your mobile phone and click to change the pitch and speed. Click on the MP3 format audio file and click + or - on the pitch change speed. At this time, you can raise or lower the pitch of the audio. Detailed steps:

1. Download the audio editing app on your mobile phone and open it.

2. Click on the MP3 format audio file and click Next.

3. Then click + or - on the pitch change speed. At this time, you can change the audio pitch and speed.

4. Click OK, the tone and speed are changing.

5. Finally, you can see the file after changing the pitch and speed, as shown below.