The Valravn's sounds are well known for me, but thanks for your recommendation. Considering bands from my region, it would be almost a sin not to mention about Kapela Ze Wsi Warszawa, better known in the world as
Warsaw Village Band. The work of that group contains traditional sounds of Masovian music dressed up in brand new electric form. I would not hesitate to share with more artists or bands if something else would come to my mind.