Dual 604 turntable

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