MaxQ - 2007 Barbershop Harmony Society International Champion Quartet - http://www.maxquartet.com
Vocal Spectrum Quartet - 2006 International Quartet Champions. An a cappella vocal ensemble, who sing in the barbershop style, dedicated to a mission of excellence in a cappella singing. - http://www.vocalspectrum.com
REALTIME - 2005 International Quartet Champions with roots in three countries, Canada, the United States and Australia, Realtime is a group with an international flair that performs all around the world. Home base is Vancouver, British Columbia. - http://www.realtimequartet.com
Gotcha! - 2004 International Quartet champions from southern California. - http://www.gotchaquartet.com/
Yesteryear - 1997 International Quartet Champions from Maumee Valley/Elyria, Ohio. - http://www.harmonize.com/yesteryear/
Suntones - 1961 International Quartet Champions from Miami Fla. - http://www.acoustix.com/ST/suntones.htm
Revival - 1998 International Quartet Champions from San Diego, California. - http://www.revivalqt.com/
PLATINUM - 2000 International Quartet Champions from Tampa Florida. - http://www.ptplatinum.com/
Nightlife - 1996 International Quartet Champions from Los Angeles, California. - http://www.nightlifequartet.com/
Most Happy Fellows - 1977 International Quartet Champions from Seattle Washington. - http://www.mosthappyfellows.com/
Michigan Jake - 2001 International Quartet Champions named after a Warner Brothers cartoon frog. - http://www.michiganjake.com/
Marquis - 1995 International Quartet Champions from Cincinnati, Ohio. - http://www.harmonize.com/Marquis/
Happiness Emporium - 1975 International Quartet Champions from Minneapolis, Minnesota. - http://www.happinessemporium.com/
Gas House Gang - 1993 International Quartet Champions from St. Louis, Missouri. - http://www.gashousegang.com/
FRED - 1999 International Quartet Champions from Marietta, Georgia well known for their parodies. - http://www.fredquartet.com/
Chicago News - 1981 International Quartet Champions from Chicago, Illinois. - http://arneberg.com/bbshop/chicagonews/
Bluegrass Student Union - 1978 International Quartet Champions from Louisville, Kentucky. - http://www.harmonize.com/bsu/
Acoustix - 1990 International Quartet Champions from Dallas Texas. - http://www.acoustix.com/
Four Voices - 2002 International Quartet Champions from Cleveland, Tennessee. - http://www.fourvoices.com/