Squeeze has dozens of new songs. Well, a dozen or so new new songs and then another batch of decades-old tunes recently unearthed.

Last year, a pal of the band found a 50-year-old high-quality recording of Squeeze founders Chris Difford and Glenn Tilbrook’s early tunes. The discovery was a shock. But the bigger shock was finding out that Difford and Tilbrook’s songwriting partnership had magic way back when they were teenagers.

“When we sat down and listened to them we discovered there was a lot of depth in them, a lot of melodic depth to them particularly” Difford told the Herald ahead of Squeeze’s Sept. 13 show at the Wang Theatre. “Considering Glenn was only 17 when he wrote these melodies it’s quite extraordinary.”

Squeeze’s current bass player, ex-Roots member Owen Biddle started producing the tracks as a new album — the resulting LP, “Trixie’s” will be out next year. For a band celebrating its 50th anniversary (marked by when Difford and Tilbrook met, not by the 1978 debut album), “Trixie’s” is a delightful time capsule.

“Fifty years ago, there was no baggage,” Difford said. “There were just two young guys writing songs almost constantly because there was nothing else to do. There were no tours, no mobile phones, thankfully. I look back at my diaries from then and I just see this young guy full of ambition who just wanted to write songs with no future planned out.”

The future that did play out was impressive. Off and on over five decades, Difford wrote the lyrics and Tilbrook wrote the music to some of pop’s best-loved tunes including “Tempted,” “Hourglass.” and “Black Coffee in Bed.” The duo are still writing, which brings us to the new new songs.

A few months after “Trixie’s” is released, the band plans to follow it up with an album of 21st century tunes — the current tour is hits-heavy but features a few from cuts from 1974 and fresh numbers.

“‘Trixie’s’ excited the new songs, and there are about 13 new songs to be finished,” Difford said. “Everytime we did a ‘Trixie’s’ track it would inspire a new song. It was a very creative couple of months where I just couldn’t put the pen down because every time we did something I was excited to write another lyric.”

Difford says after half a century, he still tries to write lyrics as he did as a teen (albeit with a bit more wit and polish).

“When you are young, you try to write from the subconscious, and that is a beautiful place to work from,” he said. “As a lyricist, I still kind of work like that. I want to be able to make mistakes and tell stories in a unique way.”

Through the middle years of their career, the pair have written a score more songs that Squeeze still hasn’t recorded. But those will have to wait as fans settle for sets of tracks penned in ’74 and ’24.

For tickets and details, visit squeezeofficial.com