Well, although you will rarely be drawing that kind of amperage, I would get protection not much less than that so there is always available power. The best is whole house or circuit protection, but some plug ins are reasonable. Understand that models like the Monster HTS5100 (also a filter...not just a surge protector...and I'm not necessarily endorsing that product for your purpose...just referencing it) limit amperage to 15a x 75% = 11.75 (roughly). That should be fine for most of your usage...but it limits the available power to 70-75% of your
potential draw. Also understand that an 1800 watt amp really needs to be on it's own 20A dedicated circuit. You'll also have the additional benefit of avoiding ground loops if you can install (or use a pre-existing) dedicated 20A circuit. I'll let the other guys recommend some specific models for you. Cheers.
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