It makes me leery when albums arrive with slogans like "The hottest Irish acoustic group on the planet" plastered on the front cover. Even if the source is The Irish Voice, I figure there are just too many superlatives adorning the covers of too many albums to give them much credence.

Happily, I discovered that Lunasa really deserves that hearty endorsement.

The band is Kevin Crawford on flute, whistles and bodhran; Trevor Hutchinson on double bass and cello; Donough Hennessy on guitars; and Sean Smyth on fiddle, whistles and viola. Guests on Otherworld are Mike McGoldrick on uilleann pipes, flute and low whistles; John McSherry on uilleann pipes and low whistle; and Stephen McDonald on flugelhorn.

Yes, flugelhorn.

It's touches like that, plus the double bass and cello, which give Lunasa a slight edge. They don't slam listeners over the head with sounds which don't belong in Irish traditional music, and yet they add subtle layers which add distinction to the sound. For instance, the bass line in "The Butlers of Glen Avenue/Sliabh Russell/Cathal McConnell's" could almost pass unnoticed, and yet it adds extra depth to the tunes. The slowly rolling bass in "Lafferty's/Crock of Gold/Lady Birr/Abbey Reel" trudges along beneath fiddles, flutes and pipes flying at phenomenal speeds, and yet the bass is an integral part of the sound, not a bit out of place.

Of course, it helps that the musicians in Lunasa are all excellent at their craft. These are tight performers, not a note out of place, and they've produced an album full of crisp, exciting tracks which force listeners to sit up and take notice. Otherworld is an instrumental album with a tendency towards frantic pacing. Sure, a few tracks amble along at a breath-quickening jog, and one or two just walk, but most of them blast out of the speakers at a full gallop.

Their arrangements are clever, allowing each of the performers to show their strengths and still blending them together into a seamless whole. "The Miller of Drohan," for example, sets the groundwork with a delicate guitar line (Hennessy) while two low F whistles (Crawford and Smyth) and a B flat flute (McGoldrick) toss the melody around. One of my favorite tracks, "Dr. Gilbert/Devils of Dublin/Black Pat's," shares the lead among fiddle (Smyth), flute (Crawford, with a bit of McGoldrick) and pipes (McGoldrick), while Hennessy and Hutchinson lay the foundation on guitars and double bass.

The flugelhorn makes its cameo appearance on "Stolen Apples." Primarily a flute and whistle (Crawford) tune, McDonald adds grace and ornamentation with his soft, brassy harmony. Hutchinson trades his double bass for an electric in "Goodbye Miss Goodavich/Rosie's Reel," but the plugged-in part is unobtrusive, accenting the tune without drawing too much attention to itself. In "January Snows/Laura Lynn Cunningham," the band mixes fiddle (Smyth) with pipes (McSherry) as if the two instruments were made to play in unison.

I could go on, but my point here is simple: Lunasa seems at first glance to be one of the most exciting new acts on the market, and they deserve the attention of all Celtic music fans. Their arrangements are traditional enough to please purists and distinctive enough to set them apart from the large and growing flock, with touches of improvisational genius to keep the tunes fresh. The challenge will be to keep these musicians -- all of whom have been involved in other bands besides Lunasa and must be, based on their obvious musical expertise, in great demand for other projects -- together and focused on putting out more in this fertile vein.