Kondo explains his inspirations and limitations with the Super Mario Bros. theme, and how Miyamoto helped

“Mario looked bigger than any other playable characters in those days and the background looked like grassland on a sunny day. So my impression was that the game would give more fun than we had experienced before. I had a number of limitations in the number of parts, the range of tone colors or tone registers, or in phonetic value. But in fact it was really enjoyable to find out what I could express! I tried to find out how much I could create and achieve within the limitations or, to put it another way, how I could utilise the limitations to create something new. I looked for suitable tunes from some CDs during that time. Even when listening to the radio, watching TV or films, I always try to find if there is a suitable tune. Along with that, I also consider the total balance of tunes and what each tune will mean to the overall gameplay as a whole.” - Koji Kondo

Not surprisingly, even Miyamoto had a hand in creating the tunes we all know and love.

“Miyamoto loves bluegrass and plays guitar and banjo very well. During that time he lent me so many bluegrass records and I really loved them. I don’t believe it was his request to compose such tunes for the game, but just because I loved them, some tunes for Mario games show influences from those tunes.”

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