Sound Over
Specifications
Yamaha's unique
design philosophy - an approach which has produced a large repertoire of the
world's finest audio components - is directly behind the development of Yamaha
tuners as well.
The Yamaha
philosophy: to provide the most natural sound reproduction quality above all
else. While this may seem an obvious approach, most manufactures actually place
considerable emphasis on improving specifications - whether the measured
improvement results in a corresponding improvement in sound quality or not. IHF
standards, for example, require tuner sensitivity specifications to be measured
at 100% FM modulation. The signal arriving at a tuner's antenna under
actual broadcast conditions, however, is only 20% or 30% modulated - a
difference that means dramatic changes in sound quality. Rather than aiming for
the best specs with a 100% FM modulated signal. Yamaha tuners are designed for
the best sound under actual listening conditions. The result is, naturally,
that Yamaha tuners offer strikingly superior sound performance.
One of the most
exemplary tuners resulting from Yamaha's unique design philosophy is T-70. This
remarkable tuner offers a 10-station random-access preset tuning system which
allows presetting of up to 10 Am and FM stations in any combination,
exceptionally accurate manual pushbutton tunung, and an improved auto-search
function that does away with the arbitrariness of ordinary synthesizer
auto-search functions. But all this tuning convenience is made really
worthwhile by the t-70's sound. The T-70 incorporates a whole spectrum of new
Yamaha technology that achieves significantly improved music reproduction
accuracy. The T-70's superior sound, convenience and overall performance
clearly reflect Yamaha's firm policy of providing nothing but the purest, most
natural sound reproduction.
Computer Servo
Locked Synthesizer Tuning System
One of the biggest
problems with conventional synthesizer tuners is that their crystal oscillator
and frequency dividers are producing RF (Radio Frequency) signals within the
tuner itself. These frequencies can leak into other parts of the tuner causing distortion,
interference and a loss of signal-to-noise ratio. The T-70 offers a brilliant
solution to this problem. The reception frequency is initially locked to
a reference frequency generated by a super-accurate "micro-fork"
oscillator. The micro-fork is a unique oscillator element, made with a special
Yamaha alloy, that offers even greater temperature stability than quartz. Once
the desired station is detected, however, the frequency divider and associated
PLL circuitry are turned off, and the T-70's Servo Locked system takes
over to lock the tuner to the frequency of the received station. This system
generates absolutely no interference - causing internal noise, and yet ensures
reliable, drift-free operation.
RF Servo Gain
Control
The T-70 is
exceptionally resistant to intermodulation distortion caused by strong
interfering stations thanks to a a unique Yamaha RF Servo Gain Control system.
When an interfering station is detected, the RF Servo Gain Control turns on
automatically to reduce RF gain by a carefully controlled amount, effectively
avoiding this kind of interference. When no interfering signal is present, the
T-70 automatically sets the normal RF gain for optimum sensitivity,
signal-to-noise ratio and sound quality.
Ultra-Linear Direct
FM Detector
This
high-performance circuit offers a simpler, cleaner signal path as well as
improved linearity compared to even the latest pulse-count detector systems.
The outstanding low-noise, low-distortion performance provided by this unique
Yamaha circuit ensures that the music signal reaches the multiplex stereo
decoder stage with no distortion added from the time it reached the tuner's
antenna.
Real-Time Direct
CMOS DC NFB PLL Multiplex Demodulator
Conventional stereo
demultiplexing systems involve turning semiconductor analog switches on and off
at a 38 kHz rate. Switvhing distortion can be a problem, however, since the
switches have a finite switching time and are located in the signal path.
The T-70 completely
overcomes this problem by using extremely high speed CMOS switches located in
the negative feedback loop of a high slew rate DC amplifier. The resulting
demodulator offers excellent stereo separation, low harmonic and
intermodulation distortion, and exceptional transient response for the most
natural FM stereo reproduction.
AM/FM 10-Station
Random Access Preset Tuning
Up to 10 AM and FM
stations can be programmed into the T-70 memory for instant one-touch tuning.
Unlike many preset tuning systems which may have 5 preset memories specifically
for AM and 5 more for FM, the T-70 random-access system lets you preset any combination
of AM and FM stations in any order up to a total of 10. You can even
program all FM or all AM stations if you like.
This is possible
because the T-70 memory not only stores the station's frequency, but the band
(AM or FM) as well. If you program 10 stations with your favorite ones first,
you'll be able to quickly call them out in order without having to switch back
and forth between the AM and FM bands. No other tuner, synthesizer or
otherwise, has ever been produced that is easier to use and listen to than the
Yamaha T-70.
Initial Station
Set
In addition to the
10-station random access preset memory system, an initial station set function
is provided which lets you pre-program any station to be tuned in every time
power to the tuner is switched on. Preset your favorite station using this
function, then whenever you turn the T-70 on you're precisely tuned in - the
perfect feature for timer recording from FM broadcasts.
Additionally, all
the T-70's memory is nonvolatile. This means that it will not be cleared or
erased even if power to the tuner is completely cut off. And there's no time
limit to unpowered memory storage as there is with backup battery, and
capacitor supplies.
Other Features
Auto DX
Anti-Interference
PLL system
Tracking Type Pure
Pilot Canceller
Pushbutton
auto-search tuning
Manual single-step
tuning
High-Q low-impedance
AM loop antenna
Selectable AM
selectivity
Built-in recording
calibration oscillator
Signal Quality
indicator
