Brach,
It’s been awhile, but I wanted to let you know that I finally got around to ordering and trying a 9V battery adapter with the Quaverato. It seems to work well, the noise is much diminished with the battery power. I haven’t tried the Quaverato with other (wall-wart powered) effects in the chain yet, but hopefully this will resolve the obnoxious (to me) noise issues I was having when I used a power supply transformer with the Quaverato. I’m not sure if the circuit could be modified to permit quieter operation with power from a power supply, but the battery power seems to confirm that the noise is generated by the power supplies that I have and used to power the Quaverato. Thanks for your help.
Mike