Full-Automatic
Direct-Drive Turntable with Quartz Lock,
Unitorque Motor, Gimbal-Suspension
Straight Tonearm
and Photo Sensor Arm Return System
This
model feature a sleek, clean design, convenient operation, and the superior
quality and reliability that advanced Hitachi technology makes possible. They
combine the proven excellence of Hitachi's Unitorque motor and quartz-lock PLL
servo system with the latest improvements in tonearm design from the Hitachi
Audio R&D labs; gimbal-suspension straight tonearm with photo-sensor return
system. Fully automatic operation with all controls on the front panel provides
outstanding convenience in each model; the HT-61S (HT-R10) gives you a few
extras. In short, these turntables leave nothing to be desired. This TH-R10 can
be used with the RM-1000 remote control center for extra convenience, too.
Unitorque - A Unique
Motor
The HT-60S is direct-drive turntables - the
platter is driven directly by the motor. Overall performance, then, is
directly dependent on motor performance. Other turntables use either multi-pole
DC motors or AC motors, which have various disadvantages. AC motors are
extremely inefficient and subject to vibrations; DC motors suffer from uneven
torque - they rotate in a series of "steps" or "puls",
which must be smoothed out by adding more poles/slots or extra servo circuitry
- complicated, unreliable, costly measures which are only partially effective.
The Unitorque motor
prevents these problems from occurring at all. It is a brushless, slotless,
coreless motor with perfectly smooth, even torque (hence the name, Uni-Torque)
its unique design employs two star-shaped flat coils positioned in such a way that
their independent torques combine to produce constantly even torque throughout
each rotation. A 240-pole magnetic rotor provides added stability. The
Unitorque motor thus features precision, reliability and efficiency superior to
other types of motors.
Quartz Lock Plus
High Torque Equals Speed Accuracy
Complementing the
Unitorque motor is a quartz-lock PLL (Phase-Locked-Loop) servo system. While
conventional servo systems must rely on a reference voltage (subject to
fluctuation due to variations in supply and temperature), these two models use
a quartz crystal oscillator, whose pulses never vary in the slightest degree.
They are compared to pulses directly from the motor so even infinitesimal speed
variations can be detected and corrected. And thanks to the high torque of the
Unitorque motor, this process occurs much faster than in conventional systems.
It all adds up to outstanding speed accuracy; wow and flutter is an extremely
low (0,025%). As an added touch, a quartz lock indicator is provided to inform
you when the turntable has reached operating speed and the quartz PLL circuit
has locked in.
Gimbal-Suspension
Straight Tonearm
The HT-60S
employ Hitachi's new straight-line tonearm design, developed through an
extensive testing process. Its low mass characteristics provide superior
tracking capabilities, and bring out all the performance possibilities of high
compliance cartridges. And its highly symmetrical, precise construction
eliminates much of the resonance that conventional cartridges suffer from. The
tonearm is mounted on a gimbal support system. This gimbal suspension allows
free movement in both vertical and horizontal directions, for optimum balance
during tracking. This means lighter, more sensitive tracking for better
reproduction quality with less stylus and record wear. An easy one-touch
anti-skating control further increases tracking accuracy by counteracting the
force which pulls the tonearm toward the center of the record.
Photo-Sensor Arm
Return System
This Hitachi systems
is clearly superior to conventional arm return methods. Ordinarily, auto-cut
and auto-return are triggered by mechanical contacts or linkages connected to
the base of the tonearm. They cause a certain amount of drag, inhibiting tonearm
movement sufficiently to produce distortion. In addition, they are subject to
wear and mechanical failure,
The photo-sensor
system is much more sophisticated. The only thing that touches the tonearm
assembly is a light beam. It passes from an LED to a photo-sensitive cell. When
the arm, reaches the end of the record, a thin plate attached to the base cuts
the light beam. This change in light intensity causes the cell to activate a
switching circuit, which in turn activates a small arm-drive motor. This entire
system is located far away from the main drive mechanism, so it does not affect
reproduction quality at all. Phot-sensor arm return - an elegant innovation
that improves performance and reliability.
Full Automatic
Convenience
All tonearm
movements are automatically controlled, and driven by a separate DC motor.
Pushing the start button initiates arm movement to the correct position over
the record and then lowers the arm. This button can also be used to interrupt
play (cut). At the end of the record, as described above, the photo-sensor
system returns the arm, then shuts off the motor. A repeat function is also
included to let you hear a record more than once without having to touch the
unit.
Specifications:
Type: Full automatic, 2-speed, quartz lock ,
direct-drive
Platter: Aluminum alloy diecast 310 mm outer diameter
Motor: Brushless coreless, slotless
"Unitorque" motor; DC motor for arm movement.
Speed: 33-13 and 45 rpm
Speed Change
System: Electronic changeover system
Signal-to-Noise
Ratio: 78 dB (DIN-B)
Wow and
Flutter: 0,025% WRMS
Speed Accuracy: 0,003%
Speed Drift
Time : 0,003% (30 sec - 303 min)
Temperature : 0,003% (5 - 35°C)
Tonearm
Type: Static-balanced, straight
Headshell: ADC type
Tracking Error: 2°
Adjustable Force
Range: 0 - 3 g / 1 turn of the balance
weight (directly readable in 0,1 g steps)
Acceptable Cartridge
Weight: 4 - 10 g
General
Dimensions (W x H x
D): 435 x 365 x 110 mm (17-1/8" x
14-3/8: x 4-5/16")
Weight: 6 kg (13 lbs 3 oz)
