Amazon purchased Musica in September 2016 for $250m.
The company said in its filing that it was looking to acquire the music instrument amplifier maker in order to “transform the business” and focus on its other products, including video game consoles and streaming music.
Musica was founded in 2011 and has raised more than $30m from investors including former Apple co-founder Steve Jobs and Andreessen Horowitz.
The $250 million acquisition is believed to be a record for Amazon, which is known for its deep pockets.
Musika is best known for building popular mobile apps for music players such as Spotify and Apple Music.
It was acquired by Amazon last year for $3.5bn in cash.