Sony STR-DA9000ES - Manual (Page 29)

ES Receivers v1.0 Page 29
Short, straight and simple chassis layout.
From Sony's early days in high fidelity, our engineers have understood
that simpler is better. For this reason, they have aimed to keep internal point-to-
point wiring to a minimum. The internal chassis layouts of the STR-DA3100ES
and DA2100ES are outstanding examples of this "short, straight and simple "
philosophy. Inputs pass directly from the back panel to the input selector,
Optimum Preamplification (OP) processing and the power amplifier, in that
sequence. It's a short, straight trip.
Analog board of the STR-DA2100ES shows Sony's smart, simple and
straight chassis layout.
OP Processing with 0.5 dB steps
Sony's Optimum Preamplification (OP) design is featured on the STR-
DA3100ES, DA2100ES and DA1000ES. The system varies the preamp negative
feedback according to the volume control setting. In this ways, Sony balances
gain and volume control settings to achieve a 10-dB improvement in signal-to-
noise ratio across most of the volume control operating range. So high-
resolution audio is reproduced against a background of silky silence.