For many years, composer/producer Brian Eno has championed the idea of ambient music (music that creates an ambience; intellectual Muzak, if you will) and he seems intent on extending to video that concept of passive involvement.

Yesterday, the National Video Festival premiered a specially commissioned Eno tape before a packed house in the Theater Lab; the show originally had been scheduled for the AFI Theater, but Eno's fondness for a reverse aspect ratio meant the picture would have to be shown on its side by the nonmovable projector there. Upstairs, the terminals were simply turned on their sides, allowing the show to go on.

The untitled tape consists of immobile but continually evolving city-scapes: The subtle changes in these urban vistas are at first fascinating, but became strangely predictable in very little time. Eno's brilliant music ranging from inspired Satie-ish piano noodling or eerie, layered swarms of synthesized sounds -- do much to relieve the visual tedium.

Several passages -- if that's what one calls the half-dozen spectral landscapes -- evoked obscure film images: "Alexander Nevsky in New York" came to mind during one particularly ominous mixture of darkening cloud and calamitous music. Elsewhere, one kept waiting for the monster to break through the clouds. Eno's tenement symphony provides an abundance of images -- dreamy pastel landscapes, subtle interplay of light and shadow reminiscent of Magritte, a quiescent urban geometry -- but there is something tedious about the total sum.

Eno's hour-long tape, which will be repeated as part of the Festival Reprise (tomorrow, 6-10 p.m.) speaks to creating a "pictorial space rather than a narrative progression," constructing a space rather than occupying one. Like the music, it is intended for such public spaces as airports or subways, but one suspects the motion of the watchers will ultimately defeat the immobility of the art.