Seven is supposed to be a lucky number, but for the Foo Fighters' upcoming album, it's all about the eights. Shortly after teasing their eighth LP with an image festooned with eights, the band has released the record's first audio teaser -- and it's an eight-second clip.

The teaser, which you can hear embedded at the top of this post, reveals about as little as you might expect, given its extremely abbreviated length. The only video is a shot of a speaker, over which Foos frontman Dave Grohl is heard screaming "All rise" a cappella. End of clip.

It might be frustrating for fans impatient to have their appetite for new Foo satiated before the new record's rumored November release. If nothing else, however, you can take comfort in the knowledge that the band is obviously confident enough in the music to engineer the sort of PR buildup that includes cryptic images and brief audio snippets -- and judging from Grohl's public remarks regarding the record, they have good reason to be excited.

The as-yet untitled project will be preceded in October by 'Sonic Highways,' an HBO series that follows the group on its cross-country journey to record new songs in a list of cities that includes Seattle, Chicago, New York, Hollywood, Washington, D.C., Austin, New Orleans and Nashville. The show, which Grohl has referred to as "reinventing the process" for the Foos, features appearances and collaborations with a number of special guests, such as Paul Stanley of Kiss, Eagles guitarist Joe Walsh, and Cheap Trick's Rick Nielsen. Whatever we hear next, it promises to indulge what Grohl has called a "license to get weird" that the band has earned after 20 years of hit albums.