just sayin’ … might be worth considering this if true and people are stretching (pushing the components a bit too far?) towards 12V
note that it has a smaller pin 2.1 - often the case for lower 9v devices ime … a 2.5mm barrel will generally be okay, but not to spec
9V centre negative is the usual studio psu for guitarists, so be careful experimenting - there are brands who do 9V centre positive (digitech iirc) on 2.1mm pins