Wow took me a while to reply to this one - sadly I'm still at the stage where I need to work to pay for the toys
If you are interested in Wadaiko, and you need audiophile recording quality, please check out "Ondekoza" who have a bigger, more aggressive and less fusion approach (they still use synths from time-to-time, though

).
I don't think either of these bands are really authentic. Then again what is. If you like Ondekoza, you could try music for the Kabuki and Noh theater which emphasize space and silence rather than percussive scale. Very interesting and beautiful, *if* you can get your head around it. There are also quite a few beautifully done recordings of Gagaku the ancient court music of Japan. But that is probably a bit too weird for all but a few intrepid souls.
In terms of latin music, there is an awful lot of choice. One left-field recording that iswell worth the effort IMO is "Black Music In Search of Oxala and Other Gods" - in the nonesuch explorer series (
www.nonesuch.com). This is Santeria music from Columbia. I can't do this record justice, so I won't try. It is a field recording from 1968, so while the sound quality is not bad, it is probably not "audiophile". I was turned onto this album only a few weeks ago, it is a sublime synthesis of African and South American black music - and a really good place to jump into the amazing music of West Africa (and Brazil, Peru etc.).
There are lots more, but I don't have the energy or patience to list them all. One other album that I have been listening to a lot recently is "Hemaviz" by Kardes Turkuler from Turkey which interleaves dense shifting rhythmic patterns and complex homophony. That makes it sound pretty severe, but it isn't. It is sophisticated pop music. Kardes Turkuler albums (and clips) can be found at
www.kalan.com