The Dual 604 is
direct drive turntable
You may have noticed
that most turntable stories begin and end with the drive system. The tonearm is
more or less an afterthought. But not with Dual. Because the tonearm can make a
big difference in how records sounds and how long they last. Which is why Dual
is very serious about tonearms in our article.
Let's consider the
604 tonearm
The straight-line
tubular design provides maximum rigidity with minimum mass. The four-point
gimbal centers and pivots the tonearm precisely where the vertical and
horizontal axes intersect. And the counter balance houses, two specially-tuned
anti-resonance filters that absorb parasitic resonances originating in the
tonearm /cartridge system and chassis.
Operation is
semi-automatic, with another uniqueDual difference: the machanical sensor.
Switch it in and you feel when the stylus is positioned precisely over the
12" and 7" lead-in brooves. At the end of play, the tonearm lifts and
returns to its post, and the motor shuts off Automatically.
Now let's talk about
the direct-drive system. It employs a newly developed DC electronic motor, with
speed regulated by a CMOS integrated circuit and digital reference circuit.
Spped accuracy is within 0,001 percent. Wow and flutter are less than 70 dB, as
with any great drive system, that's far beyond audibility.
But the important
story with any turntable is simply this. The drive system merely turns the
record. It's the tonearm that plays it.
Specifications
Drive: Electronically Regulated Direct-drive system,
Dual EDS 500
Speeds: 33-⅓ and 45 rpm, electronically adjustable
Time From Start to
Rated Speed: 2 - 2,5 s at 33-⅓ rpm
Pitch Control: Separate for both speeds, each adjustable by
means of variable resistor with calibration scale of regulation; 10%
Speed Control
(Monitoring): with illuminated
stroboscope for platter speeds 33-⅓ and 45 rpm, adjustable to 50 or 60 Hz
Sensitivity of the
Illuminated Strobe: 6 division marking
per minute at 50 Hz, 7,2 division marking per minute at 60 Hz
Platter: Non-magnetic, dynamically balanced
Platter
Diameter/Weight: 300 mm / 1,3 kg
Wow and
Fluuter: according to DIN 45 507 (GIS)
less than ±0,06%
Rumble (DIN 45
500):
Unweighted : better than 45 dB
Weighted : better than 65 dB
Tonearm: Torsionally rigid tubular aluminum tonearm in
low-friction four-point gimbal suspeension, tonearm counterbalance with two
mechanical anti-resonance filters
Effective Length of
Tonearm: 222 mm
Offset Angle: 25° 20'
Tangential Tracking
Error: 0,16°/cm
Tonearm Bearing
Friction
Vertical : less than 0,07 mN (0,007 g)
Horiziontal : less than 0,16 mN (0,016 g )
Stylus Pressure:
From 0 to 30 mN ( 0
to 3 g) infinitely variable with 1 mN ( 1/10g) calibrations
From 0 to 16 mN (0
to 1,5 g) operable from 2,5 mN (0,25 g) stylus pressure up
Power Input: apprx. 2 watts, Motor at playing operation
less than 50 mW
Power Supply: 110 V -125 V, 220 V - 240 V, AC 50/60 Hz
Power
Consumption: at Start 25 mA at Play 15
mA (220 V, 50 Hz); at Start 65 mA at Play 25 mA (110 V, 60 Hz)
Weight: 4,6 kg