"It's all been done before" Paul McKenzie sings halfway through The Real McKenzies' latest effort, Off the Leash. And though the Vancouver septet has been steadily churning out Scottish Highlands-influenced punk rock since 1992, that doesn't mean the formula is getting stale; adversely, like a dynamite bottle of Scotch, the McKenzies only go down smoother with age.

After label-hopping for more than decade, the McKenzies seem to be smitten with Fat Wreck. Their 2005 release, 10,000 Shots, saw the group polishing their sound and tackling pants-shitting riffage. The excellent licks shared by lead guitarist Mark "The Bone" Boland and bagpiper Matt McNasty were like a Gaelic echo of Thin Lizzy's trademark twin guitar sound.

The Real McKenzies are the rare outfit that improves with every new album. Though their earliest material is rollicking and rambunctious, a good deal of its charm lies in its messiness, as if you had sonic evidence of the lads getting steadily drunker and drunker in the studio. Some of it occasionally stooped to Celtic-punk cliches (see: "Scottish and Proud," "Scots 'Round the World"), but no more missteps: Off the Leash is as tight as a kilt is loose. If you want to see what 16 years of playing together can do to a band, look no further than the fantastic "The Lads Who Fought and Won," with its manic shredding, gymnastic pipes, and bass fills that would drive Matt Freeman crazy with envy. Memorials to dead World War I soldiers seldom sound so damn rocking. Paul McKenzie's vocals are as swaggering and heartfelt as ever, whether he's singing as fast as he can over crashing drums and buzzsaw guitars ("Anyone Else"), or serenading the lost cultures and landscapes of pre-colonial Canada on the doleful folk of "The Maple Trees Remembered." He embodies the Scottish bard: confident, loud, sometimes brash, but never without a hint of mournful melancholy. Equally impressive is the addition of bassist Little Joe Raposo, who appeared briefly on 10,000 Shots and contributes some truly out of control basslines to every track on Off the Leash.

Other themes that permeate Off the Leash: dogs, the road, and that ubiquitous liquid, whiskey.

On "The Ballad of Greyfriars Bobby" and "My Mangy Hound," canines both mischievous and steadfast take center stage. On the latter track, the McKenzies break new ground, introducing subtle hints of '80s synth into the melodic, kind of adorable tune. "Kings of Fife," a song about befriending "gnarly punks" in Scotland, boasts one of the album's most stirring bagpipe/guitar leads, and the bouncy melodies on "Old Becomes New" help convey Paul McKenzie's philosophy that "If you hang around long enough you'll see that everything starts to rust / Then shine it up 'til it's (pop) tip-top / And old becomes new again." And that's exactly what the Real McKenzies have done: Taken the same formula they've adhered to for more than a decade and tweaked it enough to unleash one gem of a rowdy rock and roll record.