the Bs knees?

A bloke who is an Elvis fan says he only has music under the letter E & P on his iPod (silly sod)

Which got me to thinking that the only letter you need for a mixture of variety and quality (if you could only have 1) on your iPod / iPhone would clearly be the letter B
I say clearly, because there's not another letter to beat it...

Burt Bacharach
Bad Company
Joan Baez
Anita Baker
Syd Barrett
Lionel Bart
Ray Baretto
John Barry
Basement Jaxx
Shirley Bassey
The Beach Boys
The Beastie Boys
The Beatles
Beautiful South
Beck
Bee Gees
Harry Belafonte
Belle and Sebastian
Ben Folds Five
George Benson
Irving Berlin
Leonard Bernstein
Beyonce
The B-52s
Big Audio Dynamite
Big Bopper
Big Country
Bill Haley and His Comets
Bjork
Black
Blackstreet
Black Sabbath
Black uhuru
Blair
Mary J. Blige
Blind Melon
Blondie
Blood Sweat and Tears
Bobby Bloom
Blues Brothers
Bluetones
Blur
David Bowie
Boxtops, The
Boyz II Men
Billy Bragg
Brand New Heavies
Brandy
Toni Braxton
Alicia Bridges
James Brown
Bobby Brown
Jackson Browne
Michael Buble
Jeff Buckley
Buffalo Springfield
Jimmy Buffett
Buggles
Bush
Kate Bush
Busta Rhymes
The Buzzcocks
Byrds
David Byrne

...unless you have a better letter....