Paul Allen's long-awaited remodel of the Cinerama Theater has been a subject of considerable speculation since he bought the downtown movie house for $3.75 million in early 1998.

A two-hour tour yesterday revealed that his multimillion-dollar makeover could become the best-equipped, most versatile movie theater in the world. It's set up to show 35mm wide-screen movies, 70mm epics and the extremely rare, original three-strip Cinerama process that reigned from 1952 to 1964.

The 808-seat theater is also wired to accommodate a new, reportedly spectacular technology, Electronic Cinema, that can project a movielike image without using celluloid at all. The process was recently unveiled by Texas Instruments and will be available to theaters in a few years, possibly sooner.

No official opening date has been announced for the Cinerama, but it looks as though the theater will open to the public in late April with a standard 35mm movie. General Cinema Corp., which also runs Pacific Place downtown, will book first-run films, and naturally "Star Wars" fans are hoping that the new "Star Wars" will open there May 21. However, nothing has been announced yet.

Early reports of what was happening inside the Cinerama suggested that the original's ultra-wide screen would somehow be diminished. Most controversial was the rumor that the theater would have two screens: a "flat" screen that would be used for most movies, and the original, deeply curved Cinerama screen, which would be brought out for three-projector presentations.

Allen's company, Vulcan Northwest, denied this last summer, claiming that it had simply discussed "the possibility of a two-screen scenario."

In fact, the two-screen system has been installed - although that "flat" screen actually has a considerable curve to it. It's also huge.

According to Jeffrey P. Graves of Vulcan Northwest, Allen was concerned about the distortion effects of using one deeply curved screen for everything. But he was also concerned about the "breakdown time" to convert from one screen to another. Graves initially guessed 48 hours, which was unacceptable, but the process was eventually streamlined.

It now takes eight to 10 hours to convert from the normal screen, which rolls onto a 30-foot-high pole, to a facsimile of the original Cinerama screen, which rolls out from behind. The elaborate engineering behind the system is the creation of a Portland company that helps design complex sets for Broadway shows.

The two-screen setup sounds harebrained, but it will actually deliver a clearer, less distorted picture than before. In fact, the two screens are part of what makes the theater so versatile - virtually a Cinerama museum at the same time that it will be a first-class, first-run theater.

In the past, part of the vast Cinerama screen had to be masked to show 35mm movies such as "Titanic" and the "Star Wars" reissues. Now those films will be shown on a curved screen designed for them, while the more deeply curved Cinerama screen will be reserved for films that were designed for it.

These include original three-projector Cinerama productions (1963's "How the West Was Won") and 70mm productions that were presented with a special Cinerama lens (1968's "2001: A Space Odyssey"). Depending on when the theater can line up the rare prints and equipment necessary to show these films, the original Cinerama screen could be rolled out within a year.

Already built into the sides of the theater are the booths that would accommodate the extra projectors necessary to show three-strip Cinerama. Only two other theaters in the world are equipped to present it. One is in Dayton, Ohio, the other in Bradford, England.

Designed to reflect the early-1960s era in which it made its debut, the new Cinerama looks much the same from the outside, though there will be movie poster displays that move and a marquee that can be controlled from the manager's office.

The theater is equipped with the latest digital sound systems, plus a wave-shaped ceiling designed to improve the acoustics. Cinerama presentations will make use of an entirely separate seven-channel analog sound system.

Purple curtains and red sound baffles dominate the auditorium, while the lobby has been completely redesigned, with wheelchair access in mind and with twin box offices sensibly relocated to the street and alley rather than inside the lobby. Another new, sensible feature: 10 stalls in the women's restroom.