NAMM '19 - Mattisson Bass Janek Gwizdala Master Built & Standard Series Signature Bass Demos Jason ShadrickJanuary 27, 2019VideoVirtuoso bassist Janek Gwizdala jams on his brand-new namesake collaboration with luthier Anders Mattisson.namm-20195-stringvideosgear-show-demobass-gearmattisson-bassgearspecial-featured-stories4-stringwhats-newBassNAMMVideosGear