Marina and the Diamonds perform at the Warfield in San Francisco on May 6, 2013.

Judging by the size of the venues she has been playing, it would be fair to say Marina Diamandis has had a good year. Last summer the pop songstress, who goes by Marina and the Diamonds, sold out the 1,100-capacity Fillmore. Now she’s back, still promoting 2012’s Electra Heart album, and has sold out the twice-as-large Warfield. Her current tour was booked in larger venues throughout the U.S.

“Oh my God; I don’t think two years ago I would have thought I’d have been playing 1,000-capacity venues,” the 28-year-old Welsh singer-songwriter said. “It’s weird because I couldn’t play those numbers in my own country. It feels really good.”

The album follows several archetypal female characters to tell the stories of celebrity life, broken relationships and power struggles. Diamandis also brings some of these characters alive on stage – she loves props – and parts of the show will be altered this time around. But she wants to please her new fans as well.

“Prop-wise and stylistically, there’s going to be a bit of a change,” she said. “But the main bulk of the show will be the same because even though some of the songs are different, there will be people there who haven’t seen the show.”

On her last stop in San Francisco, Diamandis heard “Primadonna,” one of her songs, on American radio for the first time. Later that summer she found herself opening for Coldplay in Europe. When it’s suggested that soon she may be headlining stadiums and a mainstream act like Coldplay could be opening for her, she retorts with a bit of embarrassment in her voice, “Shut up!”

Diamandis said she is not influenced by mainstream or modern music.

“I usually get my influences from visuals like films or photographs,” she said.

And that’s only one of the songwriter’s quirks. Another is a neurological condition that causes her to associate music notes, numbers and days of the week – among other data – with different colors. The condition, synaesthesia, allows Diamandis to sense musical tones as vivid colors when she plays the piano.

“You visualize it or you feel it; like, ‘that song has noble tones,’ or ‘that chord has a noble color,’” she said. “Or like the days of the week; they always stay the same colors to me. Friday never changes to green; it’s always red. Saturday is always orange.”

Follow Roman Gokhman at Twitter.com/RomiTheWriter.