Although the copyright date on the back cover says 2010, Time Slips on By's official release date was Jan. 18 of this year. So it is all right, I guess, to nominate it as the first essential blues album of 2011, a resistance-is-futile set of passionate modern blues, electric and acoustic, with pronounced downhome accents. As do all memorable recordings, it rewards obsessive relistenings -- believe me, I know -- and yields some fresh marvel with each return.

In recent years the mandolin, an instrument popular with African-American stringband musicians as blues evolved out of Southern folk music, has started to reappear in the hands of contemporary blues performers. Perhaps none is more assured at it than Rich DelGrosso, not just an expert performer but a published scholar of the instrument's role in blues and other American vernacular genres. His "Mandolin Man" on the current disc is a spirited celebration of departed heroes such as Charlie McCoy, Johnny Young and others. He is also an accomplished slide guitarist, and the album opens with a hoary but exhilarating country-blues slide riff before flying into the hard-charging DelGrosso/Jonn Del Toro Richardson original "Baby Do Wrong," a true juke-joint tour de force.

Not everything, though, is quite so implanted in deep rural soil. Guitarist Richardson, who heads his own Texas-based blues outfit, has a different notion of roots, namely old-school, horn-driven rhythmic blues (as in the self-penned title tune) and uncompromising Gulf Coast sounds. Even so, his gorgeous "Katalin" feels like something Lonnie Johnson could have written; besides, its melody more than echoes the one associated with the traditional folk-blues "Louise." Richardson and DelGrosso, masters individually and together, meld their styles so that no tape or stitch is to be seen or heard. Their songwriting skills, again conjoined or separate, are actually what struck me first, before it hit me how much that is strikingly creative is going on in the arrangements.

Consider, for example, Joel Guzman's accordion. Not that accordions have never been heard in blues before (usually in zydeco bands), but they're not played with something akin to conjunto inflection. Guzman's restrained, understated grounding of "Katalin" transports the listener into an altered state of pleasure. And then, once more, there's DelGrosso's mandolin as it plays off against Richardson's sharp-edged guitar and the menacing grumble of the Texas Horns in "Shotgun Blues," a DelGrosso composition inspired by mandolin-blues legend Yank Rachell.

Besides the singing, the playing, the arrangements and the songs, all of which will persuade you that life is worth living after all, Time offers up some laughs. Richardson's "Summertime is Here" bows to a couple of other songs: Martha & the Vandellas' "Dancing in the Street" with the lyrics "Summer's here and the time is right for dancing in the streets," subsequently parodied in the Rolling Stones' "Street Fighting Man" as "Summer's here and the time is right for fighting in the street." Richardson's priority, however, is more laid back: "Summertime is here, it's time for barbeque and beer." (Come to think of it, if Time brings a food and a beverage to mind, it's those two.) There is also a harmonica player who claims to be named Sonny Boy Terry, and who are you and I to doubt the lad?

Time Slips on By, to quote an antique blues lyric, is how you want your rollin' done. Don't let the year slip on by without it.