audio-talk

Take a 15VA toroidal transformer with mains supplying the primary, and draw a certain amount of power through it within its design spec.

Take a 150VA toroidal transformer with the same mains supplying the primary, but draw the same power, at the same current and voltage as you did for the 15VA transformer.

Would there be more magnetic field interference from the bigger transformer? If so, I'm guessing from the mains primary?

Thanks.

1. Depends on the two transformers being built to the same standard. Most leakage is from the lead outs as they break the symmetry of the windings.
2. Consider the case of the two transformers with no load. The current in the primary will be the result of the leakage flux in the primary as there is no where else for the energy to go.
3. The larger transformer will have a lower flux density for a given power supplied (more core area, same power) that may lead to less leakage.

In other words I don't know, but suspect it depends,