I would've thought headphone quality mattered, but my boss heard the effect through iPhone earbuds. The effect is fairly subtle. To make it as clear as possibl

I would've thought headphone quality mattered, but my boss heard the effect through iPhone earbuds. The effect is fairly subtle. To make it as clear as possible, try leaving it on for a couple minutes, then switch it off and listen for a bit. Or, play this example, which is the clearest demo I've found: https://www.dropbox.com/s/t5dvah8zke3uky8/HellOfAGuy_demo.mp3 https://www.dropbox.com/s/t5dvah8zke3uky8/HellOfAGuy_demo.mp.... The song's played twice—with and without the filter.