Aimée Portioli is a Berlin-based Dutch-Italian composer and sound designer who records and performs as Grand River.

Portioli makes experimental electronic music with rich emotional colours. Her work, influenced by minimalism and ambient music, is atmospheric yet rhythmically complex, incorporating a wide range of contemporary compositional and production techniques.

The name Grand River evokes nature, scale, and movement, all key forces in Portioli’s work. Her first release as Grand River was 2017’s Crescente, which was named by XLR8R as one of the best releases of the year. She followed this with her debut album Pineapple (Spazio Disponibile, 2018), which garnered praise from The Quietus among others, while its follow-up Blink A Few Times To Clear Your Eyes (Editions Mego, 2020) was positively received by Resident Advisor and The Verge, and was elected among best albums of 2020 by Inverted Audio.
Her work has separately appeared on compilations by Ghostly International, Tresor, and Longform Editions.
In 2023, her third album All Above, found its way back to shelves under Editions Mego. Then, in 2024, the new collaborative effort In uno spazio immenso emerged, a joint venture with Abul Mogard, debuted on Caterina Barbieri's light-years label.

In addition to her studio albums, Portioli also creates original sound art installations and worked with 4D spatial sound on several occasions. In 2025 she released her latest album Tuning the Wind which was created as an installation piece.

Portioli has performed as Grand River at major international venues and festivals, including Barbican Hall, CTM Festival, MUTEK, Centre Pompidou, MUTEK, Kraftwerk, Funkhaus, WOS Festival, Berghain, and many more.
Since 2016 she runs the label One Instrument that invites artists to respond to a unique creative brief – to create a piece of music using just one instrument.

Aimée Portioli holds a bachelor’s degree from the Faculty of Linguistics and Communication of Milan. Her thesis explored the psychology of the communicative function of music in media.
Her work today is motivated by similar questions of sound and music as a form of communication that goes beyond language.