Silverline Audio's aftermarket power supplies have been carefully analyzed for compatibility. They have a center negative pin that is required by these products. Do not use positive center pin power supplies with these units! It will damage them.
This Silverline Audio aftermarket replacement AC Power Adapter is designed to be compatible with the following Roland Products:
Sound Brush SB-55
A30 MIDI Keyboard Controller
DIF-800 Interface

Features:
Save money on batteries!
Slim Design Frees up Space on Power Strip by Occupying One Outlet
Input Volt Range: 100-240V (Worldwide Compliant)
Safety standard compliant: FCC, CE, RoHS
Safety Features: High Efficiency and Reliability, Automatic Overload cut-off, Automatic Thermal cut-off, Short circuit and Over Voltage protection

Specifications:
I/P AC:100V~240VAC
50-60Hz
O/P DC:9V DC 1A
Cord: 36in
Tip: (-)center, (+)outer