Hours before his concert last Sunday, US singer-songwriter Jason Mraz preached the importance of 'song karma' - or treating music with respect. So if you're listening to a song on the radio and you want to switch it to something else, you shouldn't do it abruptly, or else there will be dire consequences. 'If you just kill a song, that's when it comes back to haunt you,' Mraz says. 'Three days later and you can't get this awful song out of your head ... because you changed the song impolitely without fading it out.' Mraz never made that mistake at the concert, as many of his songs appeared to go on and on, much to the delight of the packed house at the AsiaWorld-Arena. In his trademark straw fedora, he started with Freedom Song, which set a fun and lighthearted mood for the night. For the breezy love song Lucky, which Mraz sang with back-up singer Merritt Lear in a much slower tempo, members of his band got a chance to do mini-solos on the trumpet, trombone, saxophone, violin, piano, double bass and electric guitar. Things became very intimate with You and I Both, as the band left the stage and Mraz performed alone, sitting on an equipment box. It felt like a performance at a coffee house, which is where his career first gained steam. The cheery track was sung as a touching ballad, leaving the audience in muted wonder. Then Mraz jumped into a mash-up of Curbside Prophet and The Remedy, tongue-twisting hits from his mainstream debut album Waiting for My Rocket to Come. The crooner's vocal range was impressive, particularly on the operatic part of Mr Curiosity. The show wrapped up with the 'little hippie song' (his words, not mine), I'm Yours. The crowd clapped, sang along and danced as he repeatedly yelled out the chorus like a mantra. But after fans stomped and cheered for more, Mraz - who showed remarkable stamina in the 2 1/2 hour show - did a three-song encore which included his favourite, 93 Million Miles, as snowflake-shaped lights were beamed around the arena. Mraz's album may be called Love is a Four-Letter Word, but it takes seven letters to sum up the night: awesome.