Does anyone know how I can create a dual supply from an SMPS single supply DC adapter? This is for an audio circuit. It needs to be able to deliver at least 1 amp, ideally more than that. It also needs to filter out all of the high frequency switching noise from the SMPS stage. I've been trying to use a push pull configuration with BJTs and a "virtual ground" but still seeing a lot of noise on my scope. I put a couple of RC low pass circuits in series to the base of the transistors, but the noise is getting through.