Automatic Hi-Fi
Stereo Turntable with Direct Drive
Featuring:
Shock-proof
free-floating sub-chassis
Straight
tubular-aluminiumtonearm with de-coupled adjustable counterweight
Very low-friction
tonearm bearings
Light detachable
headshell
Automatic diameter
selection and positioning of arm on start of record.
Automatic stop, arm
lift and return at end of record.
Hydraulically damped
arm lift
Anti-skating
adjustment for spherical and elliptical styli
Direct readout of
stylus force.
Controls
for 33⅓ and 45 rpm, Start and Stop.
Pitch controls with
3-LED-bar actual speed indication
Attractive tinted
dust cover with friction hinges.
The AF777 has a high
standard of performance. Rumble, for example, is better than -65 dB (DIN B),
and wow and flutter is less than 0,05% (weighted rms).These very good figures
are attributable to the thorough design and construction of the various sub-sections
of the turntable; the suspension, tonearm, headshell, and especially the Direct
Control electronics which regulate so precisely the speed of the turntable.
To ensure that the
record always rotates at exactly the right speed, the rate of rotation of the
turntable itself is continuously monitored and regulated by the Direct Control
electronics. The turntable, which is belt-driven from a separate Dc motor, has
a tachometer built into it. The output of the tachometer is accurately
converted into a d.c. voltage whose level is proportional to the actual speed
of the turntable. This signal is continuously compared with a stable d.c.
reference signal. If anything tends to alter thr turntable speed the
tacho-derived signal will differ from the reference; this difference causes the
Direct Control electronics to immediately accelerate or slow down the drive
motor sa as to correct the speed of the turntable.
In addition to
improving rumble, wow and flutter and drift specifications, direct control of
the turntable speed has the important advantage that the record speed is
unaffected by external influences such as the drag ofa cleaning device or
different stylus force. Similarly, the Direct Control electronics compensate
for fluctuations in temperature or line voltage and frequency.
Top Quality Tonearm
The straigh
tubular-aluminium construction of the tonearm gives it an ideal combination of
lightness, strength and rigidity, mechanical properties sa vital to a top
quality tonearm. Because it is straight, with the stylus on its longitudinal
axis, and since the aluminium headshell is so liht, the tonearm's
centre-of-gravity lies very close to its axis. Consequently, torsional forces
on the arm are minimal. This helps to eliminate unwanted high frequency
resonances and keeps the natural resonance of the arm, with the cartridge, to
an acceptable low frequency.De-coupling of the tonearm's counteweight provides
wideband damping.
Low Friction
Bearings
Horizontal and
vertical friction forces in the bearings have been reduced to an exceptionally
low value (better than 15 mg), so that there is almost no resistance to
movement of the arm. As a result, the stylus is aable to faithfully follow even
the most delicate modulations in the record groove.
Minimal Tracking
Error
Geometric
characteristics of the tonearm, such as offset angle and location of the stylus
on the tonearm's axis, have been designed to minimise tracking error (better than
0°9'/cm)
Excellent
Trackability
The exceptionally
small tracking error, combined with very low bearing friction, ensures the
excellent trackability characteristics of the tonearm. This is one tonearm
which allows full advantege of the trackability of the chosen cartridge.
Free-floating
Sub-chassis
The turntable and
tonearm assemblies are mounted on a
separate sub-chassis which is suspended from the main chassis via three
nickel-chromium leafsprings with butyl-ruber dampers. This free-floating
sub-chassis type of suspension is a wellprvoen and extremely effective
technique that achieves superb mechanical isolation of the turntable and tonearm from the main
chassis.
Rumble-free,
shock-proof and protects record and stylus
The mechanical
isolation of the turntable and tonearm has been further improved by careful
lacation of the springs and by using material with the best possible damping
properties. Suspension of teh motor from the main chassis has also helped
improve isolation. The result is that rumble from the motor is virtually
eliminated, and external disturbances, such as vibration and acoustical
feedback are not transferred to the cartridge. Even quiete violent knocks to
the outer casing will not cause unwanted acoustical noises. And, the valuable
stylus and records are better protected from accidental damege.
Specifications
Turntable
Speeds: 33⅓ and 45 rpm
Wow &
Flutter: better than 0,08% DIN ( better
than 0,05% weighted rms)
Rumble: better than
-43 dB (DIN A); better than -65 dB (DIN B)
Pitch Control
Range: ±3%
Speed
Indication: 3-element LED-bar
Tonearm Type: Tubular-aluminium
Tracking Error: Better than 0°9'/cm
Bearing
Friction: Better than 15 mg, vertically
and horizontally
Resonant
Frequency: 10 Hz (with test cartridge)
Effective
Arm Length: 215 mm (8½ inches)
Effective Moving
Mass: 16,5 g
Anti-skating
Adjustment: For spherical and elliptical
styli
Cueing Lever: Hydraulically damped
Headshell: Die-cast aluminium
Stylus Force:
Range : 0 -3 gf
Indication:direct
readout
Turntable
Material : aluminium
Diameter : 320 mm
approx.
Power Supply: 110 V, 60 Hz ; 220 -240 V 50/60 Hz
Current
Consumption: 0,1 amperes
Dimensions (W x H x
D):
Dust
cover closed : 420 x 141 x 348 mm (16½" x 5½" x 13¾")
Dust Cover Open :
420 x 335 x 385 mm
Weight: 5,8 kg (12,8 lbs)
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