The power supply in the GamuT D200 has its own cabinet inside the main cabinet. It is made of a special magnetic soft iron, that after the cutting and bending process is oven-heated 8 hours to optimise its magnetic properties. It is then coated to prevent it from rusting. Why do we spend money and effort to do all that? Stray electromagnetic fields are now absorbed better, as they prefer to go through the iron instead of the air. Some amplifiers have covers around the transformers. However, the wires to the large capacitors also radiate a field.