The standard for metal
Amazing sound, I use this speaker in my Boss Katana Artist Mk2 and I love it. If you're into cleaner genres with lots of effects, then there are better options out there (or just don't touch the stock Katana), but if you're shredding some distorted metal, your sound won't get any better than this. Clean, warm sound without any cracky or buzzy noise, as opposed to the built-in speaker in the Katana.