Vertical
Format Linear Tracking Fully Automatic LSI Logic Turntable Unit
1 -
Linear Tracking - A Major Advance in Turntable Performance
Many disc
audition problems arise because conventional tone arms swing in an arc across
the disc from a single pivot. This innovative unit features linear tracking
with the stylus and tone arm traveling in a straight line across the disc,
foiiowing precisely the same path as the head of the cutting machine that made
the disc. The improvement in performance is clearly audible, and marks a moajor
step forward in turntable unit design.
2 - The
Linear Tracking Mechanism
To keep
the cartridge stylus always precisely at right angles to the disc groove, two
sensitive optical sensors detect the slightest deviation from the proper
tracking position. The unbalanced signal from the two sensors actuates a
servomotor that immediately moves the tone-arm base the correct distance in
towards the center of the disc. Therefore, as the groove spirals inwards, the
tonearm assembly moves across with it. This system is so sensitive that it can
respond accurately to the differences in the pitch at which the groove was
cut (loud passages are cut at a larger
pitch). The high precision servo-motor drives the tone-arm assembly via a
specially wound stainless steel wire, wire tension is kept constant by spring
loading and the servomotor rotation is applied by a worm type reduction gear.
This system holds the tone-arm assembly firmly in position unlike linear motors
where the assembly is free to slip and slide. The entire tone-arm assembly
rides on a mirror finished high precision rod of nonmagnetic stainless steel,
providing stability and rigidity.
3 - Low
Tracking Error Means Superb Trackability
Conventional
tone arms have tracking errors of several degrees. The LT-5V tracking error is
never greater than ±0,1°, a dramatic improvement in the ability of the stylus
to trace the groove accurately. The result is a reduction in distortion that
shows itself in better definition of the stereo sound field and a more
realistic recreation of the original atmosphere of the performance, with each
instrument clearly located. All cartridges will benefit from this improvement
the better the cartridge, the greater the advantage.
4 - A
Short, Straight Arm with Fewer resonances
Conventional
arms suffer two important disadvantages. In order to reduce tracking error,
they have to be made as long as possible, and they have to set the cartridge
off at an angle to the pipe (usually by putting an "S" or
"J" bend in the pipe). Increased length means greater effective mass
or, if a lighweight material is used in an effort to reduce mass, the tone arm
has a stronger tendency to resonate. The short, straight arm of the LT-5V
achieves greater strength and reduced resonances using a structure of stainless
steel, giving a sound that preserves the full impact of transients and
excellent definition right down into the deep bass region.
5 -
Improved Stereo Channel Balance
Since the
stylus is always at right angles to the groove, there are effectively no
unbalanced forces on the stylus. Not only does this remove the need for
inside-force cancellers. It also preserves channel balance and separation,
ensuring much more faithful reproduction.
6 -
Vertical Configuration Improves Feedback Margins
Vibration
from speaker systems can sometimes cause acoustic feedback to the stylus tip
and serious loss of high-level listening quality even when it doesn't result in
a continuous "howl' that prevents normal listening. The vertical turntable
configuration is much less sensitive to feedback than horizontal units because
the vibration from the speaker systems is at right angles to the motion of the
stylus in tracking the groove.
7 -
Simple,Accurate Dial-Setting of Stylus Tracking Force
The tone
arm hangs vertically down, statically balanced in all three dimensions for
completely stable and accurate tracking of the groove. It is therefore able to
follow even warped discs - and cope with vibrations - with much less tebdency
to skip out of the groove.
The
vertical format has another important advantage; since the weight of the
cartridge itself acts at right angles to teh tracking forcee. It has no effect
on it. So once the right tracking force has been set, there is no need to
re-balance and reset it when swap ping cartridges. And the simple dial-setting
adjustment of tracking force could hardly be easier to use.
8 -
Record Clamp and Stabilizer
A spring
loaded clamp secures the disc to the vertical turntable. Hinging completely out
of the way for convenience, it snaps into position positively, and applies a
slight pressure that brings the disc into contact with the dished turntable
mat. It thus acts as a disc stabilizer, reducing vibration and improving the
crispness of bass response. The upper edge of the clamp has a scale that
corresponds with the scale above the tone-arm assembly. Use these two scales to
locate any track you want to play,, and to guide the stylus precisely to the
lead-in groove.
9 -
Double Flywheel Drive System
In
addition to the flywheel effect of the turntable itself there is a second
counterweight flywheel. Together, they are accurately dynamically balanced for
smooth and stable rotation, with high precision bearings.
10 -
Fully Electronic Auto Control
The brain
of the comprehensive automatic functions is an LSI computer on a chip specially
developed by Mitsubishi Electric. It takes the signals from the push-button
controls and from the photoelectric sensors that detect the presence and size
of the disc on the turntable, and guides the stylus unerringly to the lead-in
groove, automatically choosing 45 rpm for 7" and 33 rpm for 12"
discs. It also enables a number of other useful and unusual automatic
functions.
11 -
Optical Display
LED
indicators show the movement of the tone arm in real time, whether to left or
right and up and down - they cease to indicate once the stylus is on the
surface of the disc. The LED tracking error indicator gives a quick and
positive indication of serious tracking errors. It is also useful in checking
that the arm is hanging perfectly vertical.
Specifications
Drive: Phase-locked loop belt drive by DC servomotor
Platter
Diameter: 304 mm 912") diecast Al.
Olatter
Weight: 1,3 kg (2lb 14 oz)
Moment of
Inertia: 300 g/cm/s²
Speeds: 33 and 45 rpm adjust. ±3%
Speed
Selection: Auto/manual
Wow and
Flutter: 0,045% WRMS
Signal-to-Noise
ratio: 65 dB (IEC-B); 76 dB (DIN B)
Tonearm
Type: Straight universal, static
balanced
Overall
length: 223 mm (8-3/4")
Effective
lebgth: 180 mm (7-1/8")
Tracking
Error: ±0,1°
Headshell: GFRP (6,2 g)
Cartridge
Weights: 10 - 20 g
Power
Consumption: 14 W
Dimensions
(W x H x D): 466 x 430 x 200 mm
(18-3/8" x 17" x 7-7/8")
Weight: 12,5 kg (27 lb 8 oz)
