After a two-year hiatus, the Esplanade's popular music festival Mosaic returns in September in a different, more compact form.

Instead of its 10-day format, Mosaic Music Weekend will take place from Sept 1 to 4, with each of the four days dedicated to a music genre: jazz, singer-songwriter, electronic/pop and rock.

Headline acts include Japanese jazz pianist Hiromi, British singer- songwriters Lisa Hannigan and Patrick Wolf, South Korean electronic band Idiotape and rock duo Tomgirl, comprising Singaporean Cherie Ko and Melbourne- based Ted Dore.

While there have been several standalone performances under the Mosaic Music Series in the past two years by the likes of Mexican acoustic rock guitar duo Rodrigo y Gabriela and singer-songwriter Rufus Wainwright, the Esplanade says the team has been taking the opportunity "to observe and to recalibrate - to see how we can better serve the evolving needs of our artists and audiences".

Programmer Melissa Poon, 26, says: "While audiences have been supportive of the standalone Mosaic Music Series presentations, there is an intensity of music experience that can be achieved only when more programmes are aggregated together over a longer period."

The curtains came down on the Mosaic Music Festival in 2014, the same year it marked its 10th year.

The festival, which had featured an eclectic mix of genres including hip-hop, world music and electronic music, is widely credited with diversifying the concert scene in Singapore.

However, it appeared to have been crowded out by the entry of multi-act concerts featuring non- mainstream acts such as the Laneway Music Festival.

In 2013, the Mosaic festival drew a crowd of about 90,000, which was down from 135,000 in 2012 and 120,000 in 2011. The Esplanade no longer releases attendance figures for its shows.

At the Mosaic Music Weekend, Tomgirl are taking the opportunity to launch their self-titled 10-track debut album on Sept 4 at the Esplanade Recital Studio.

Ko, 25, says they have been fans of the festival all along and she relishes the opportunity to be featured alongside regional and international acts. The show will also be the band's live debut.

Dore, 28, says: "We will be performing all tracks from start to finish with a surprise cover thrown in."

He also reveals that there will be an elaborate light show and projections, which he describes as a "visual onslaught".

Just like its longer festival format used to do, the Mosaic Music Weekend will introduce several acts performing in Singapore for the first time, including a double- bill with the Mercury Prize nominee Hannigan and Wolf. Both will be showcasing new music.

Hannigan, an Irish folk singer, will come to the Mosaic Music Weekend with material from her August release At Swim, her third album. English multi-instrumentalist Wolf, who has six albums to his name, is on his Wildsound Tour.

One of the returning acts is cutting-edge Japanese jazz pianist Hiromi, who brings to the event her Trio project comprising Grammy- nominated bassist Anthony Jackson and former Toto drummer Simon Phillips. She last played at the Mosaic Music Festival in 2006.

Tickets, ranging from $25 to $88, go on sale from July 28 at the Esplanade's box office and Sistic.

During the Mosaic weekend, free performances will also feature at the concourse and outdoor theatre by acts such as home-grown singer Alemay Fernandez and the Oliver von Essen Piano trio, Singapore roots-rock band Cheating Sons, looping maestro Randolf Arriola, indie electronic band Riot !n Magenta and the Philippines' eccentric indie rockers Oh Flamingo!, The Observatory's Leslie Low and T-Rex, a home-grown band made up of members of Anechois, Amateur Takes Control and Sphaeras.

Watch out for singing policeman Lewis Loh, whose performance of Home with other musicians from the Singapore Police Force went viral last year and got a thumbs-up from Prime Minister Lee Hsien Loong.

Loh, 20, who is serving national service in the police band, will be performing a 45-minute set of originals under the moniker Lew.

While he has performed at the Esplanade on several occasions, he says it is humbling to be recognised as a singer-songwriter. "It's a reminder that I should keep going because I've been doing this for only about a year and now I get to play at Mosaic," he says.