This version of the AD-900 contains the more rare two Panasonic MN3005 chips and was apparently sold only in Japan till 2000. After 2000, the AD-900 was made with four MN3008 chips and production ended in 2003.
It is reported to have 600 milliseconds delay time — double that of the AD-80 and AD-9. See a review of the AD-900 at HarmonyCentral.
