I bought my Small Clone in 2017 and have been using a Truetone 1SPOT 9V adapter to power it. The Truetone adapter is a center-negative power supply but I noticed that the EHX Small Clone’s instructions state “For optimum performance, use a 9V battery, although a 9V 100ma tip-positive AC adapter with an 1/8″ plug can also be used (not included).” Don’t the instructions mean that a center-negative power supply would not work to power the EHX Small Clone because the pedal requires a center-positive or tip-positive power adapter? Then why has my center negative Truetone 9V adapter worked excellently to power my EHX pedal? I called the guitar store where I bought both the EHX Small Clone and the Truetone power adapter but and I really didn’t understand the explanation the store clerk gave me. He said the unit was “positive and negative polarity”. That just left me with more questions! Can someone please explain to me why the Truetone 1SPOT 9V power supply/adapter works for the Small Clone? I am very confused!