Most of the vampire devices are items I don't use regularly.
I'm going to move them to their own strip, so that they will
always be off, except when actually being used.

You can get an idea just from the temperature of the device when
it is on standby. Cold devices can be ignored. I've found the worst
offender in all my AV equipment is the cable box.

The Parasound was always slightly warm, despite its size, so the power it
pulled was not surprising. But a unit with a "compact" power supply might be
warmer -- in that area -- than a unit that pulls more power, but whose
supply uses a bigger transformer or is further from the cabinet's cover.