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Soundwave on 19 March 2013
The chip likely costs a lot because Nintendo insisted on a highly customized chip that could fit into a small casing and only draw about 33 watts. To get a chip to only consume that much power requires a lot of work and R&D and Nintendo is the one that paid for it.
If they weren't so obsessed with that niche need, they probably could've gotten a more off-the-shelf (but more powerful) chip from AMD for cheaper even.
