History may never know exactly how the 23 String Band got its name, because the five-man group from Cumberland Valley, Kentucky plays more strings than that with any onstage musical configuration they use. The answer may be as simple as a member once told a reporter interviewing them: “We've always been into prime numbers, you know?”

Math aside, music critics' varied comments are a sideshow in themselves, ranging from “Imagine if all of your best buddies got together, drank a little bit, and then found out that they were all freakin’ awesome musicians,” to “The group describe it as 'Original Hillbilly.' Which would be true, if the original hillbillies had listened to Paganini and the Beastie Boys.”

The latter reference is to Violinist Scott Moore, who started playing at the age of four and writing music at age six. He’s played Carnegie Hall and held solo seats with classical orchestras.

Bassist T. Martin Stam holds two degrees in music performance, and has studied at the feet of Yo-Yo Ma and Wynton Marsalis. Banjo player Curtis Wilson, on the other hand, emulates the style of his grandmother’s next-door neighbor Dave “String Bean” Akemon.

Perhaps the most representative example of reviewers' reactions is the description, “A hard-driving, leg-shaking, new kind of old-timey.” That sort of raging variety is on clear display in their two CDs, “The 23 String Band” and “Catch 23.” But the full impact of the prime-number experience, most observers agree, comes at one of the band's live shows: “Electrifying,” as one publication puts it. “Their vocals are as tight as the cork in a jug of moonshine, and their high-powered music kept the crowd dancing well into the night.”

23 String Band's vocal chords and picking skills will be all warmed up for the Beartrap show; they're midway in a seven-state tour, with the Casper stop sandwiched between destinations in Missoula, MT and Nashville, TN.

The 23 String Band with a live medley of “Cripple Creek” and “Wild Bill Jones,” at Red Barn Radio in Lexington, KY:

The band onstage in Knoxville, TN playing the John Hartford original “The Long, Hot Summer Days”:

The 23 String Band, with a front-porch version of their song “Girls”: