Actually the pedals operate on DC not AC, but the adapter is taking in AC from the wall. Recent pedals are of the same standard, 9v, negative center. Vintage pedals are usually of a different standard. To be sure just look out for any markings on the pedal :wink:
I'm currently using a 1spot to power my pedals. I won't consider it very quiet, but it's good enough. It's probably one of the best pedal power supplies you can get locally. It works internationally too, 100-240v. If you want the top of the line power supply you can give the voodoo power 2 a try, but I don't think you can find it in Singapore. It is not international voltage friendly either.