Most of the Boss pedals require the normal PSA adapter, while some has a sticker that says ”ACA” on them. What’s the difference, and how can I make them work in my setup? To answer these questions and a few more, let’s start at the beginning. History In 1978, Boss launched the Compact pedal line, and all the early products were small current consumers. The OD-1 draws about 4mA, and the CE-2 (introduced in 1979) draws about 8mA. The first adapter Boss sold to go with the pedals was called the ”ACA-xxx” (where ”xxx” denotes the mains voltage, so the US one was called ”ACA-120”, while the EU one was called ”ACA-230”). This adapter was unregulated (as the current draw grows, the output voltage drops) and even though they were labeled ”9vDC”, they did put out roughly 12 volts DC at a normal load. So each pedal was fitted with a diode and a resistor, to drop the incoming voltage to roughly 9 volts DC. As the pedal range grew, the current consumption of each new pedal grew as well. The larger current draw of the new pedals didn’t fit the unregulated adapter system very well – remember that the … Fortsätt läsa Boss ACA & PSA – what gives?