As technology becomes more advanced, the need for custom toroids becomes that much more necessary. Toroids allow for devices to run safely, quietly, and efficiently. Considering that most devices are different, toroids must be unique and highly customizable.
The size and weight of a toroid should be dependent on the height ratio to the diameter of the toroid. Mechanical design is the most important aspect of the size and weight of toroids. If toroids are designed to be too big, then they will not fit in the device.
Toroids do not create electro magnetic radiation at high levels. This is a result of the air-gap in the core. Some devices produce more EMR than others, and so custom toroids can be fitted with magnetics shields that go over the circumference of the transformer.
The way in which a toroid is wound relates to its ability to reduce mechanical humming. Spacing between winds can be greater if there is low mechanical noise.
Voltage regulation changes from toroid to toroid. Knowing the amount of energy needed to power your device will help in the creation of custom toroids.
Different toroids work in different devices. It is best to get customized toroids.