Instrumental rock has come in a variety of forms over the years, ranging from '60s surf groups like the Ventures to the folk-rock fingerpickers (acoustic guitarist John Fahey and his numerous disciples) to the Steve Vai/Joe Satriani/Randy Coven school of hard rock shredders. But Low Frequency in Stereo is an instrumental group that doesn't fall into any of those categories -- well, at least they are instrumentalists most of the time. Recorded in 2003 and released in 2005, Travelling Ants Who Got Eaten by Moskus finds the Norwegian band using vocalists on a few of the selections (including "Man Don't Walk" and "Slow Train Coming," both of which feature female singer Jomi Massage). Some hardcore fans might question that move, asking, "If jazz can be dominated by instrumentalists, why can't alternative rock have the occasional instrumental group? Is it really necessary for Low Frequency to add vocals?" But truth be told, the Norwegians are still instrumentalists at heart -- instrumentals dominate this alt-rock/lo-fi outing, and this release isn't following the example of the Bar-Kays (a great soul/funk outfit that started out as an instrumental group à la Booker T. & the MG's but became totally vocal-oriented in the '70s). Even on the vocal offerings, this album always sounds like a Low Frequency in Stereo project; vocals or not (usually not), the Norwegians maintain a recognizable, appealing sound that is as spacy and quirky as it is infectious. That infectiousness prevails whether they are incorporating jazz on "Hazelwood" and "Element," garage rock on "Limousine," or surf rock on "The Sun and the Moon and the Stars in the Sky." When bebop alto saxophonist Frank Morgan featured Abbey Lincoln on one of his albums, it didn't make him any less of an instrumentalist -- and similarly, the occasional use of vocalists doesn't compromise Low Frequency's identity one iota on this risk-taking CD.