Esoteric AZ-1 Reference Manual

Esoteric's new model AZ-1, a "Class D" integrated digital amplifier
combined with a master clock sync generator, is powered by a "WB"
wound core transformer
A WB* power transformer is a wound core type transformer, a new technology which offers
highly efficient and outstanding performance for its size dimension.
The WB power transformer incorporates a very unique "reversed" design concept to its coil
and core structure in that the steel core is wound to the coil.
*WB = Wound Core type Transformer with Coil Bobbin
1. High speed, consistency and highly efficient power supply ability.
The WB transformer incorporates a wound steel core that surrounds the coil. This innovative
design ensures the maximum performance of the steel core.
Fig.1 below shows a simplified model of the magnetic paths of WB and conventional
transformers.
The WB design ensures the shortest magnetic path from the coil (because the coil surface
and the core surface are at a constant distance at the same radius) and the magnetic path
generated from the coil fully magnetizes the steel core without any loss. This creates a
power output supply is more constant than other designs.
From an audiophile perspective, the end result is similar to the high end sonic characteristics
achieved by tube equipped integrated power amplifiers.
Thanks to this magnetically efficient design, the WB transformer responds directly to the
requirements of current need, as requested by the drive circuit. This results in lossless power
output, high speed response and ultra efficient power supply ability.