Is there a way of changing Google Play Music's default "uknown" album art?

[AC Question]

I want to change the album art for songs without actual album art. If I would know where the picture is, I could just replace it. Any idea? Or are there any other good ways of replacing it?

 

[Devlyn16]

I know you can change the album art because I have used some custom art for some tunes. I did so through chrome browser on a PC though. it is where you edit the track name etc. click on the picture and you can delete it or select another IIRC