EMAD Onyx bass drumheads deliver increased low-end response and powerful attack, with the incredibly cool look of matte black and the ability to hone your tone with EMAD. Onyx bass heads are made with a single 10mil ply, complete with EMAD foam rings to adjust the head’s attack, focus, and sustain. Sonically, EVANS Onyx black bass drumheads have a more defined attack, with a relatively short sustain, and a darker tone to match the aesthetic. This coated drumhead also features Level 360 Technology.