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ABOUT THE T955
Designed specifically for home theatre and custom installation set-ups,
the NAD T955 Power Amplifier delivers uncompromising performance.
It combines supreme reliability, flexibility, and performance with
outstanding value. Flexibility has always been an important part of
NAD components. Such flexibility is particularly important in home
theatre and other multi-channel systems. That’s because it is common
for a multi-channel system to incorporate different brands and
models of loudspeakers. Often these speakers have different levels
of efficiency. The individual input level controls for the five channels
of the NAD T955 make it easy to compensate for such differences
in efficiency, and achieve the ideal system balance. Ample dynamic
headroom of the T955 ensures that the very wide dynamic range
of modern cinema soundtracks and digital music sources will be
preserved. In addition, the T955 will handle low impedance speakers
with ease.
The T955 incorporates NAD’s unique Soft-Clipping circuitry in all five
channels. Any amplifier can be overdriven if it is played too loud,
exceeding the maximum output power. Under such circumstances,
amplifiers produce extreme high levels of distortion which, besides
sounding very unpleasant, can damage your loudspeakers. The Soft
Clipping circuit suppresses such distortion and minimizes the risk
of damage to speakers. This is particularly important with movie
soundtracks which often contain very dynamic outbursts in which,
unlike music, it is difficult to hear this potentially damaging distortion.
The Soft Clipping LED on the front panel illuminates when the Soft
Clipping circuit is engaged. Soft Clipping can be defeated with a rear
panel switch.
The 12V trigger connection on the back panel allows the amplifier to
be switched from On to Stand-by and vice-versa remotely. This way,
the T955 can be part of a system which can be turned on and off with
a single command, easing operation. The 12V trigger also allows the
amplifier to be installed in places not in easy reach.
THE DESIGN
The NAD T955 houses five individual amplifiers, each on separate
circuit board. Each amplifier channel acts as a “mono block” within
the chassis. Each input connector, and set of loudspeaker output
terminals, is directly connected to that channel’s circuit board.
This design eliminates extra wiring and keeps signal paths short.
Furthermore, this modular design increases reliability and thermal
efficiency. The input circuit uses a totally new dual differential input
topology that operates in true Class-A mode. The special Holmgren™
toroidal transformer has less hum and magnetic leakage than
conventional toroidal transformers, but retains the usual benefits of
high efficiency and high power-to-weight ratio.
Ruggedness and reliability are critical in custom-installed systems.
The T955 uses a combination of fuses and non-intrusive electronic
protection. This provides highly effective protection that does not
effect audio performance. Each channel is protected against excess
temperature, DC fault and loudspeaker short-circuit. The T955’s
inherently conservative, high-voltage/high-current output stage has
been designed for years of trouble-free service.
POWERDRIVE
To meet the diverse requirements of high current drive and high
dynamic power, our patented PowerDrive amplifier circuit will build
further on our reputation for amazingly effective power. By adding
a second high-voltage rail to our well regulated high-current power
supply, we get an "overdrive" that can nearly double the continuous
power on a short term dynamic power basis. This is a further
development and refinement of our renowned Power Envelope
circuit, utilized by NAD in the 80's and 90's. PowerDrive differs from
Power Envelope in that it offers greater amplifier stability and low
impedance drive capability, resulting in less distortion when driving
real speakers with real program material.
