There were two bands and one radio show called Mainstream. 1. Mainstream was a jazz quartet in the 70's: Jan Ptaszyn Wróblewski (ts, co-leader), also listed here as Jan Ptaszyn Wroblewski; Wojciech Karolak (org, co-leader); Marek Bliziński, listed here as Marek Blizinski (el-g); and Czesław Bartkowski, listed here as Czeslaw Bartkowski (dr). They released one album Mainstream, Polish Jazz vol.40, which contained 5 well-known standards and Karolak's composition Dookola Wojtek (w/ W.Karolak). 2. Mainstream were popular britpop band in late 90's. Mainly in Poland, UK and Germany. They signed cotract with Nude Records and released only one album 'Mainstream' (1998). .