Producers Henry Binns and Sam Hardaker, with their project Zero 7, have long been leaders in the field sometimes called downtempo music. The genre mixes the electronic and the organic, the modern and the retro, and usually features intimate vocals in slow songs that are melodic but can quite easily blend into the background for your romantic dinner date or trip to a trendy furniture store. Zero 7’s vocals have been supplied by a number of singers, including José González, Tina Dico, and Sophie Barker, but most notably by Sia Furler, who sang on the duo’s first three albums before turning full-time to a successful solo career.

Binns and Hardaker say they have been reinvigorated by new guest singer Eska Mtungwazi, who sings lead on four tracks on their fourth album, Yeah Ghost. There is a more pop and R&B sound to Zero 7 this time around, and whether that’s a good thing or bad is a matter of taste. Check out the comments on Amazon to get a load of the outrage — most of which is directed at Mtungwazi — coming from Zero 7’s disappointed longtime fans. “Can I have my money back?” asks one fan.

To a neutral listener, the new Zero 7 doesn’t sound much different than the old. I agree with the fans who say that Mtungwazi engages in a little too much of the kind of vocal histrionics that have marked female R&B singers in recent years…but, frankly, so did Dico and some of Zero 7’s other singers. Even Furler hams it up from time to time. The real difference with Yeah Ghost is that Zero 7’s music is stepping out of the background.

ZERO 7: House of Blues, Thursday, December 17, 7 p.m. 619-299-2583. $22.50.