Koto concert between April 9 and 30

we will travel in Japan from the 9.4 - 30.4 . we will be happy to see a traditional Japanies concert ( koto etc.). thanks for any recomendation.

Gagaku concert in Kyoto Imperial Palace will be held on April 9. (Free)
10:00,11:00
http://www.kunaicho.go.jp/e-culture/gagaku.html
April 30
Tokyo, National Grand Theatre
10:45 Open
It has not yet been posted to this page.
http://www.ntj.jac.go.jp/english.html
Please check here in the top right corner of the e-mail.
http://www.sankyoku.jp/concert.php
April 16
Tokyo, National small theater
This is already the launch of the ticket is started.
Not only the music, even dance there.
http://www.ntj.jac.go.jp/schedule/kokuritsu_s/2016/4941.html?lan=e
http://www.ntj.jac.go.jp/schedule/kokuritsu_s/2016/4996.html?lan=e
On April 29,
It seems there is a koto concert in Osaka, National Bunraku Theater, but contact method seems the only phone.
http://www.ntj.jac.go.jp/schedule/bunraku/2016/5171.html?lan=j
April 17
Kyoto, Rohm Theater
http://rohmtheatrekyoto.jp/english/program/300/
April 24, 12:00 start
At Tokyo, Nihonbashi Auditorium, a concert of Koto (Free)
http://ichihashi.info/hp1/?p=1991
http://www.nihonbasikokaido.com/
1-31-1 Nihonbashikakigara-cho, Chuo-ku(Ward) , Tokyo
Nihonbashi Community Center
There is if you look to the other.