TU-3 requires the BOSS PSA Series AC adaptor (sold separately).
Important:
Voltage and plug types differ by region. Use a regionally compatible adaptor that matches your local power specifications.
Voltage and plug types differ by region. Use a regionally compatible adaptor that matches your local power specifications.
Note: The TU-3 draws 20 mA (DC 9 V) to 80 mA (DC 9 V, when High Brightness mode is on). Any PSA adaptor (200 mA/500 mA) is compatible. However, if you are supplying power to other effects pedals via the TU-3's DC OUT jack and the total current consumption of the TU-3 and connected pedals exceeds 200 mA, use a PSA-S or PSA-S2 adaptor. To learn more about the PSA series, see also this article: BOSS PSA adaptor: Specification Differences by Model
Caution: Use only the specified PSA Series adaptor. Use of any other adaptor may cause malfunction or damage to the unit.