Sony DVP-NS9100ES, NS3100 manual Construction & Design, Twin R Core Transformers NS9100ES

Construction & Design

Twin R Core Transformers (NS9100ES)

The digital processing and control circuits can introduce noise to the power supply voltage, which can trigger subtle audio distortions. To protect the audio circuitry, the DVP-NS9100ES uses two separate power transformers: one for the servo and digital system and another just for the analog audio and video systems. The analog power supply is further divided, with independent transformer windings for analog audio and analog video. This reduces interference between audio and video circuitry to a bare minimum. In addition, power supply regulation on the audio circuit board itself helps establish stable operation for the audio D/A converters.

Power transformer cores and windings can vibrate and degrade the sound, radiating 60 Hz hum into nearby audio circuits. That's why Sony chose an R- Core design. The R stands for round. Not only is the core round, it has a cylindrical cross section, enabling the transformer windings to be wrapped without the voids or gaps that permit vibration. This results in far less radiation, far less hum. These two transformers are mounted on a non-magnetic copper plate, which is quite effective in reducing vibration, flux leakage and the consequent noise and distortion. The audio power supply circuit also incorporates discrete components, including electrolytic capacitors, carefully selected for their sound quality.

The two power transformers have round cores with cylindrical cross sections. This enables far more consistent transformer windings—for far less radiated hum.

ES DVD Players 2005, Version 4.0 Page 39