High-Inertia,
Belt-Drive, Arm-less Turntable with Vacuum Disc Stabilizer
An
Integration of Record Disc and Turntable Platter by Means of Vacuum Suction.
Total Banishment of Modulation Caused by Warp or Resonance of Record Disc.
VACUUM DISC
STABILIZER
The playback
method of record disc has been unchanged for all ages -- simply to put a disc
on the platter and then to place a pick-up on the disc. But this simple
operation comprises various problems. Among others, what cannot be neglected in
terms of sonic quality is self-resonance of the record disc. Such harmful
additives not contained in the original signals have to be removed by all means
for purest fidelity reproduction.
So far, many
audiophiles have tried to make improvements in this respect utilizing so-called
audio stabilizer of special platter mat. But no definite solution has been
given to the problem of this noxious modulation triggered by a slight warp or
resonance of the disc itself.
The V.D.S.
system is to integrate the record disc and turntable platter, so to say, to
make a record disc of high inertia. By removal of the air between the disc and
platter, atmospheric pressure changes itself into a stabilizer, which works
evenly throughtout an entire surface of the disc. This is truly an ideal
turntable system.
The PD-300
is the first turntable incorporating the discc sucking system, where a vacuum
pump of simple robust construction is employed with application of the theory
of bellows. To suck out the air, grooves and sucking hole are provided on the
surface of the platter, and the air passage inside the platter is connected to
the pump by means of tube.
The pressure
given to the sound grooves is equivalent to placement of 30 kg stabilizer in
terms of weight,, and perfect stabilization effect is ensured.
Suction and
its release can be done by simple one-touch operation of the suction lever
provided at the front of the cabinet, thus ensuring easy accessibility.
Normally the lever is placed horizontally, and when it is turned upright,
sucking function is activated. When the specified level of suction is reached,
the indicator turns from orange to green. This indicator functions quite
accurately by sensing the vacuum degree between the platter and disc.
The idea of
the V.D.S. system came from the disc-sutting lathe. But the system employed at
the lathe is to sustain the vacuum state by keeping sucking, which
inevitably causes noises and vibrations.
Therefore, with the PD-300, to keep airtight the special sealing pads are
placed on the surface of the platter positioning on the outer and inner rings
of sound grooves of LP disc. Thanks to the pads, once sucked, the vacuum state
can be sustained for long. The pad remains unchanged in quality for long time,
but for eventual replacement it is so designad as to be easy in installation.
The object
of the V.D.S. system is to remove harmful resonance from the turntable having
perfect basic performances. Thus it is important to remove unnecessary
vibrations in the rotation mechanism, not to speak of improvement in such
fundamentals as S/N ratio, speed accuracy, etc. In this respect, the belt-drive
system is used, and the motor is placed away from the orbit of the cartridge to
evade influence of its flux and vibration.
The
high-inertia platter having 3,5 kg weight and 500 kg/cm² inertia moment is driven by a high-performance, brushless, slotless DC
servo motor that turns slowly at the ratio of 10 times as compared with that of
the platter, which helps suppress vibration, and now totally noiseless rotation
is realized by huge amount of energy thus obtained.
UNIFIED
STRUCTURE
From Bearing
Portion to Arm-base Fixing Portion to Remove Resonance. In Addition, Double
Insulation System to Shut off External Vibrations.
The ultimate
style of turntable is that only the stylus tip vibrates on the solid base where
all portions are integrated from the bearing to the tonearm. The PD-300 is
perfectly unified in this respect with provisions for interchangeability of
tonearm. The unified main chassis of solid bearing and arm-base receptacle is
made by die-casting of aluminum, to which a heavy arm-base is fixed by 6 bolts.
Then put the platter and tonearm, and the sturdy-built frame of the PD-300 is
now completed. On top of the suction effect, thanks to this unified structure,
all sources of undesired vibrations are eliminated from the playback loop,
namely, record disc - turntable - tonearm. Brilliant birth is now given to
truly "Non-Resonant" turntable
system.
Effective
Insulator
Impeccable
counter-measures are provided against external vibrations as well. One is the
main insulator inserted between the main chassis and the heavy cabinet of solid
structure, and the other is the large-sized sub-insulator provided at the legs
of the cabinet. This double-insulation system safeguards the function of
"non-resonant" body from external vibrations.
3 main
insulators are placed on the main chassis, which hangs and damps the integrated
playback block from the main cabinet. Here featured is LUX's exclusive 2-step
damping insulator. The high-compliance natural rubber supporting the shaft
cuts-off the vibrations of small amplitude, while combination of spring and
biscous brake of silicon grease effectively works against those of large
amplitude. The horizontal balance of the platter can be adjusted by these
insulators.
The large
sub-insulators using natural rubber of good quality are provided at the 4 legs,
which not only support the cabinet but damp the vibrations from the placement
base. These insulator allow horizontal adjustment of the entire turntable.
Abundant
Accessories
Fine
Adjustment of Rotation.
You can
fine-tune the turning speed while monitoring the stroboscope placed beside the
platter. Independent adjustment is posible for 33 and 45 rpm formats by means
of controls provided underneath the cabinet. The strobo pattern displayed by
blinking light of crystal oscilator provides precise adjustment of the turning
speed.
Overhang
Adjustment
Generally
speaking, the overhang adjustment requires much time, as the fixing screws of a
cartridge have to be loosened. With this unit, the overhang can be easily
adjusted by turning the arm-base, as the fixing hole of the arm-base for your
tonearm is drilled out of its centre. Furthermore, the fixing hole for the bolt
at the main chassis has sufficient tolerance and its subtle adjustment ensures
the optimum overhang.
Heavy
Arm-Base (optionaly available)
It is a
well-known fact that in the whole playback system of audio components the
change at very input and output, i.e., cartridge and loud-speakers causes the
most conspicuous variations to the tonal quality of playback sounds. Therefore,
some have such wishes to interchange various components depending on the music
sources, et. Also many desire to have special combination of their own at this
input section of the turntable system according to their personal taste. To
cater for such requirements of audiophiles the PD-300 employs a detachable
arm-base for easy replacement of tonearm. This heavy, feedback-resistant
arm-base is made of planed aluminum plate having 88 mm thickness which can be
firmly fixed by 6 bolts. 4 different kinds are prepared for sale on option, and
you can use most tonearms available in the marketplace.
Specifications
Phono Motor
Section
Driving
System: Belt-drive
Motor: Brushless and Slotless DC Servo Motor
Turntable
Platter: Aluminum-cast
Diameter
: 300 mm (12")
Weight
: 3,5 kg (7,7 lbs)
Inertia
Moment: 500 kg/cm²
Rotation: 33-1/3 and 45 rpm
Adjustable
Range of Rotation: ±3%
Wow and
Flutter: no more than 0,03% (WRMS)
Signal-to-Noise
Ratio: better than 60 dB (IECB)
Run-up Time: within 3 seconds
(within ¾ rotation for 33⅓ rpm)
Power
Requirement: 110 - 120 0r 220 - 240 V,
50/60 Hz
Power
Consumption: 15 W
Dimensions
(W x D x H): 490 x 390 x 200 mm
(19,6" x 15,6" x 8:)
Weight: 18 kg (39,6 lbs) net
Additiona
Features
Vacuum Disc
Stabilizer: manual type
Stroboscope: Illumination by built-in quartz oscillator
Acrylic
Cover: 4 mm thick, detachable, 1,8 kg (4
lbs)
Insulator: Double Insulation System with Horizontal
Balance Adjust Facility
Tonearm
Base: Detachable