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I've used a good few of those fancy Toto do it all bidet sprayer dryer toilets, most of which (as the toilet isn't designed for a single gender) have the flush noise function. Department stores are a good bet, as are mid market restaurants.
It's really nothing to write home about though. It's the sound of a flushing toilet, which I'm sure you've heard before. Whatevs though, boats and floats and that.