Boss · Multi-Effect

SY-300 Guitar Synthesizer

9V · 400 mA · maker

Boss SY-300 Guitar Synthesizer power requirements

9V DC · polarity not stated · draws 400mA
digital · from the maker
“Power Supply AC adaptor Current Draw 400 mA” source
Voltage: “PSA-120S … Input Voltage AC 117 V (50Hz/60Hz) Output Voltage DC 9 V Maximum Current Output 500 mA” source
Checked 2026-10-14

255 × 191 × 70 mm (10.04 × 7.52 × 2.76 in)

Width × depth × height, from the manufacturer.

Each has an output that can power it, checked against its published figure. Plan the whole board to see what runs everything.