Bubbling Under: B. Smyth Builds 'Leggo' at R&B Radio

Each Friday, Billboard presents "Bubbling Under," a weekly look at new and noteworthy acts making their way toward Billboard chart success. Up this week: B. Smyth, Boy, Del Marquis and Brian Weaver

With his debut single "Leggo," featuring 2 Chainz (Motown/IDJMG), building below Mainstream R&B/Hip-Hop and Rhythmic, 19-year-old B. Smyth's buzz keeps growing. The crooner gained early attention on YouTube singing covers of R&B hits, including Frank Ocean's "Thinkin Bout You" and Avant's "Separated." His version of Miguel's "Sure Thing" was posted on worldstarhiphop.com, garnering label attention and boosting the standing of his YouTube channel, which sports 4.6 million views, 1.6 million courtesy of "Leggo."

Swiss/German duo (singer Valeska Steiner and bassist Sonja Glass) makes its first appearance on a U.S. Billboard chart, as "Mutual Friends" (Nettwerk) enters Heatseekers Albums at No. 13. Hooky lead single "Little Numbers" aids its exposure with a 24% increase in plays as it approaches the Nielsen BDS-based triple A chart. The song has also received placement on the iTunes Store's home page. The set reached the Germany Albums top 10 in 2011.

New cuts from a Scissor Sister! The band's guitarist, Del Marquis (real name: Derek Gruen) releases his debut full-length album, "Cosmos," on March 26. Recorded under the name Slow Knights, the 10-song independently-released set features Gruen playing on every track (and singing on one), as well as former members of Prince's the New Power Generation. Guest vocalists, including Rod Thomas (Bright Light Bright Light), also appear on the pop/soul album, which Gruen produced. Thumping first single "Shame" drops March 19.

Brian Weaver gains momentum with "Rain or Shine," which stirs below Christian Songs. Although he's just now seeking his first chart ink, the Phoenix native is a seasoned worship leader. He performed for six seasons at Young Life youth summer camps and has opened for established acts including Jars of Clay and Tenth Avenue North. Released on the independent VSR imprint and distributed via Capitol Christian Music Group, "Rain" appears on his second album, "Let Love In," released last fall.

Reporting by Keith Caulfield, Wade Jessen, Rauly Ramirez and Gary Trust of the Billboard charts department.