Went to the Pioneer website and under SC-37 information, it had this posted!
This answers my question as to why my VSX-94 doesn't shut down with 6 ohm speakers, but my SC-25 does! Apparantly, these newer models are more prone to shut downs....
"My AV receiver says OVERLOAD and shuts off, what should I do?
Poor wiring connections, bad wires or a bad speaker may cause this. As you increase the volume, you will increase the amount of current you are drawing from the receiver. To troubleshoot this issue, try the following:
1.Disconnect each speaker wire connection. Inspect for any frayed or damaged wiring and replace it.
2.Check the impedance of the speakers; make sure they are properly rated for your stereo. In most cases, they need to be 8 ohms. Only a few Pioneer receivers will support lower impedance.
3.If the problem still continues, try these steps:
1.Turn the receiver off.
2.Remove one speaker.
3.Turn the receiver on.
4.Increase the volume.
If the receiver overloads, repeat steps 1-4 (selecting a different speaker each time). If you disconnect a certain speaker and the receiver no longer overloads, have this speaker checked at a service center. It could have a bad speaker component, like a tweeter, sub-woofer, or even a bad crossover."