British singer Amy Winehouse performs at the Brit Awards at Earls Court in London in this February 20, 2008 file photo.[Photo/Agencies]

Two previously unreleased songs from Amy Winehouse aired on radio stations this week ahead of her posthumous album, generating mostly positive comments from critics and bittersweet memories for fans.

The reggae-infused track "Our Day Will Come" premiered on BBC's Radio 1 station on Thursday and is a cover of Ruby & The Romantics's classic song. Another, "Like Smoke," is a collaboration with rapper Nas, and it premiered on Wednesday on New York's Hot 97 radio station.

The December album, "Amy Winehouse Lioness: Hidden Treasures," was announced on the late singer's official website earlier this week along with the 12-track listing, which includes alternate versions of Winehouse's hit singles like "Valerie" along with unreleased tracks and new compositions.

NME magazine's Dan Martin was one of five journalists invited to a secret listening session for her album last month. He described "Our Day Will Come" as "perhaps more the real Amy than the one that the circus would have us remember."

Martin said the Nas collaboration "Like Smoke" was "one of the most nerve-wracking of the whole record," as the rapper had been drafted to complete the unfinished demo after Winehouse's death in July.

The Guardian's Casper Llewellyn-Smith, also at the listening session, voiced concerns over whether some of the earlier demos polished up for the upcoming album would live up to Winehouse's own standards.

"There are certainly times when her vocal on a song sounds more like a sketch, even if she was an instinctive artist who appreciated the magic of capturing a first take," said Llewellyn-Smith.

Winehouse's fans have received the new tracks positively on Facebook and Twitter, calling it "gorgeous" and "bittersweet."

The singer was found dead at her London home in July, age 27, due to what coroners later said was five times the legal limit of alcohol in her system.