NORTH TONAWANDA — For the first time in years, the Trans-Siberian Orchestra will play in Buffalo during a nonwinter month.

And that suits Paul O’Neill just fine.

O’Neill, founder of and writer for the group, spoke during a recent phone interview about the band’s pending theater tour. The focal point of the 31-city tour will be the band’s latest album, the gold-certified “Night Castle,” as well as the long-awaited staging of the band’s third album, “Beethoven’s Last Night.”

Having just come off of another successful holiday run — TSO’s 2009 Christmas tour saw the band perform before more than 1.2 million fans, including a packed house at HSBC Arena in December — the band is glad to finally bring “Night Castle” to life, O’Neill said.

“In rock, there’s a rhythm — write, record, finish and tour for one or two years. (The annual holiday tours) just meant that right in the middle of recording ‘Night Castle’ in particular, every November everything would shut down ... we would tour for eight weeks ... and then go back in the studio,” he said. “ ‘Beethoven’ would have been toured years ago, but we just wanted to finish ‘Night Castle.’ ”

When TSO was created in 1996, O’Neill pitched the band to the record label (Lava/Atlantic Records) as a full-on rock opera group. The intention was to complete two trilogies — one relating to Christmas and one not — but the success of the group’s Christmas material (two platinum albums, “The Christmas Attic” and “The Lost Christmas Eve,” and one double-platinum album in “Christmas Eve and Other Stories”) put the nonholiday material on hold.

“The Christmas trilogy got bigger than we could have ever imagined,” he said. “Christmas is too large a subject. It’s too big for me to put on one album. In the entertainment world, Christmas is the holy grail.”

O’Neill’s grand vision, also a holy grail of sorts, was equally attainable. In the mold of Emerson, Lake and Palmer and The Who, O’Neill wanted to use grandiose orchestras and a dozen or more vocalists to tell a story. The influence of Beethoven, one of O’Neill’s primary inspirations, can be identified in “Night Castle” as well as the TSO album that bears his name.

“To me, Beethoven was the first heavy metal rock star,” O’Neill said. “TSO’s rock operas are about subjects that are larger than life. Every rock opera tells us the story first in prose form and then again in poetry form.”

While the story remains the same, the setting will change. Spatial constraints have compelled the TSO crew to minimize its stage production — which is known for pyrotechnics, lasers and big, bold set pieces — in favor of smaller items that can fit in theaters. While this past holiday tour saw TSO take 38 tractor trailers full of lights from city to city, the upcoming theater tour will see only five tractor trailers accompany the group.

“We’ve accomplished a lot of our goals in arenas,” said O’Neill, who said the group’s tendency is to want to go bigger and better every holiday season. “ We were a little scared to go back in theaters ... but now everyone’s psyched. We’ve done it before, but we got used to stadiums. If we wanted something bigger, we could just build out the set. We can’t do that this time.

“There’s something about theaters that’s magical. It’s intimate, not just from the fans’ point of view but the musicians’ point of view ... It doesn’t let you get into a comfortable rut.”

Plus, O’Neill said, Buffalo should treat him and the band better in April.

“It’s just a great rock town, but the cold cuts through you,” he said. “In the dead of winter, you can’t move your hands there (outside in the cold).”

“Can’t” seems to be a word that TSO’s members aren’t used to hearing much. Once this tour is over, TSO will work on an outdoor summer tour that will feature a set piece about which O’Neill was ebullient — a 100-yard-wide pyrotechnic piece that’s meant to create an eight-foot wall of flames, which dance up and down to the music. There’s also a Broadway production that’s in the works (which O’Neill hopes to debut in a couple years) and the third part of the nonholiday trilogy, which has tentatively been titled “Romanov: What Kings Must Whisper,” about Russia’s Bolshevik Revolution in 1918.

Whatever the band endeavors next, O’Neill said that TSO’s supporters will be the inspiration.

“The bottom line is bands exist for their fans,” he said. “Our job is to give the best music with the most emotional impact for the lowest price and to constantly push the envelope.”

IF YOU GO

• WHAT: Performance by Trans-Siberian Orchestra

• WHEN: 7:30 p.m. April 15

• WHERE: Shea’s Performing Arts Center, 646 Main St., Buffalo

• MORE INFORMATION: Call 847-1410 or visit sheas.org