NAMM '16 - Friedman Bill Kelliher Signature Amp Demo Rich OsweilerJanuary 24, 2016VideoThe Mastodon guitarist talks about and plays through his labor of love with amp guru Dave Friedman.friedman-amplificationwhats-newmastodonvideosbill-kellihertube-headnamm-2016gear-show-demospecial-featured-storiesampsgearGearAmpsVideosNAMMReviews