NAD T770 사용자 설명서

T770 Surround Sound Receiver

Most A/V receivers available on the market today focus predominantly on 
the Video and Surround Sound aspects, leaving audio circuitry almost 
as an afterthought. NAD firmly believes that there are many people for 
whom music will always come first so. With NAD’s reputation for high value
/high performance it was obvious that the Model T770 would have to 
please Audiophiles and Videophiles alike.

Design
By doing away with many costly and superfluous features, NAD’s engineers 
concentrated only on the truly important parts of an A/V receiver. As the
new Digital Surround Sound formats allow for the same wide bandwidth 
and large dynamic range for the rear channels as the rear channels, all five 
channels are capable of putting out an equal amount of power. As usual 
with NAD, the T770 uses discrete output stages only, including the 
surround channels. The benefits of this approach have been proven over 
the years in many acclaimed NAD amplifiers and receivers. The integrated 
output modules favored by so many other designs will deliver a decent 
amount of power under laboratory conditions, driving an 8 ohms resistor, 
but can have great difficulties in driving real world loudspeakers.

Impedance Sensing Circuitry (ISC)
The new Impedance Sensing Circuitry (ISC) topology designed by Bjørn 
Erik Edvardsen allows the T770 to deliver maximum performance under 
virtually any circumstance, independent of the loudspeakers it is driving. 
The circuitry automatically recognizes the impedance characteristics of the 
loudspeaker and  will then adjust its power supply settings to best cope with 
that specific load.
NAD takes a stance to the mindless “brochure power” approach which doesn’t 
give a realistic indication of an amplifier’s true capabilities. Instead, the ISC 
topology is a practical approach to enable an amplifier to easily deal with 
dynamics and difficult loads. More meaningful are the T770’s dynamic 
capabilities; up to 300 Watts into 2 ohms and up to 40 amps current capability.

Whereas it is widely accepted with CD players that the digital and analog 
circuitry play a vital role in the performance, it appears that many AV 
receivers employ only mediocre signal conversion and processing 
circuits. For the T770 the engineers choose the best available within the 
budget: Burr-Brown DACs with 18-bit resolution. The two DSP chips that 
handle the Dolby Digital, Dolby Pro Logic, EARS and other Surround 
Modes chosen, are from the well renowned Motorola 56000 family. The 
combination of these components ensure that the integrity of the original 
signal retains its full resolution and dynamics.

Flexibility
As one would expect from any NAD component, the Model T770 offers 
great flexibility; 5 video and 4 audio inputs allow you to connect all your 
sources with ease. All video in and outputs are S-Video and Composite 
compatible, including the video input on the front panel.
Besides these "normal" inputs, the T770 also sports an external decoder 
(5.1 channel) input so you can easily expand your receiver in the future 
with an outboard decoder for another surround sound format, such as DTS, 
for instance. 3 Digital inputs are provided, to cater for every eventuality: 
A coaxial digital input, an input with a RF demodulator integrated and a TOS 
Link for sources with optical outputs. Whether it' a Laserdisc, CD and/or 
DVD player, the T770 will connect to it. With pre-amplifier outputs for all 
channels you can easily upgrade your output power too.
To ensure long-term contact reliability, all speaker terminals are of the 
robust binding post variety rather than the usual spring clips and all other 
audio sockets are gold plated.
The remote control handset supplied with the Model T770 also has controls 
for NAD CD players or changers and a (dubbing) cassette deck. With NAD 
Link it is possible to remote control other NAD products which do not have 
their own remote control (NAD Cassette Deck Model 616, for instance ) 
from the T770’s remote control.