Sona Stream, a Web3 music streaming marketplace, has launched with a $6.9 million seed round from Polychain Capital, Haun Ventures and Rogue Capital. The platform allows artists to sell "digital twins" of their songs as SONAs (Music NFTs) to collectors, who can promote the songs by sharing them on social media. SONA owners receive 70% of the streaming revenue on a pro-rata basis, while artists get 30%. The company redistributes the revenue every two weeks, proportional to how much the specific song is streamed. Sona currently features music tracks from several artists and aims to raise the number to over 16 million tracks by 2024.