What about interference from transformers on audio equipment

A: Toroidal transformers have very small magnetic leakage and are used in large numbers in audio equipment. However, if you do not pay attention when winding, its leakage magnetism will increase and produce noise interference. The most common problem is in the winding of the secondary low-voltage winding, due to the number of turns is small, will be divided into several groups of small sections wound on the same level to reduce the insulation thickness and coil thickness, resulting in increased magnetic leakage. The correct method should be each winding along the circumference of the ring core of the direction of uniform interwinding, this winding method of leakage inductance is minimized, leakage magnetism is also minimized, no noise interference. If the secondary is low-voltage high current, can be used more with the wire and winding method. It is not allowed to wind several windings on the same level.