Alan Peake wrote:

The PC PSU filter toroids seem to be optimized for the 25KHz -85KHz
range so any applications you have for this frequency range could use
them. Similarly, the AC input to the oven is probably 50/60HZ so those
toroids would be better at the lower audio frequencies.

Not quite sure about beads - ordinary ferrite material has fairly
constant permeability up to a frequency determined by the ferrite mix,
then drops off. Beads tend to have an impedance peak at some desired
frequency range - e.g. 100-200MHz
Alan

Thanks very much - that encourages me to try them and see how well
they perform.

Regards,

Mike Monett