What is stereo?




There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.




H.H. Scott '59





Dual 1249 turntable

Single-play / multi-play , belt-drive turntable with fully automatic start and stop, plus continuous play. 

Mode selector paralleles tonearm to record in single-play for accurate vertical tracking.

True, four-point gimbal centers and pivots the tonearm mass at intersection of horizontal and vertical axes. Tonearm is dynamical balanced in all planes. The four needle-point pivot are first hardened, then honed, a process which produces microscopically smooth surfaces. The prcision ball-bearing races are only 0,157 inch diameter.

Unique "Vario-pulley" used in Dual three belt-drive models is precision-machined for perfect concentricity and balance. Speeds are adjust by expansion and contraction of pulley circumference, belt is never twisted or distorted.

 


For several years, independent surveys of component owners - audio experts, hifi editors, record reviewers, readers of the music/equipment magazines - have shown that more of them own Duals than any other turntable. This is quite a testimonial to Dual's quality performance, reliability and fully automatic convenience.

We believw the new 1249 will add even more serious music lovers to the roster of Dual owners, as it provides every feature, innovation and refinement long associated with Dual turntables plus some new ones. And all in a newly designed chassis that complements the superb design and meticulous engineering of the 1249.

The low-mass tubular tonearm pivots in a true four-point gyroscopic gimbal suspended within a rigid frame. All tonearm setting are easily made to the exacting requirements of the finest cartridges. The tonearm is vernier adjustable for precise balance, tracking pressure is calibrated in tenths of a gram; anti-skating is separately calibrated for conical, elliptical and CD-4 styli. Tracking is flawless at pressures as low as a quarter of a gram. In single play, the tonearm parallels the record to provide perfect vertical tracking. In multi-play, the Mode Selector lifts the entire tonearm to parallel the center of the stack. All operations are completely flexible and convenient - and they are foolproof. The tonearm can be set on the record manually or by using the viscous- damped cue-control or by simply pressing the automatic switch. You also have the options of single-play, continuou-repeat, or multiple-play. The dynamically-balanced cast platter and flywheel are driven by an 8-pole synchornous motor via a precision-ground belt. Pitch is variable over a 6% range and can be conveniently set to exact speed by means of an illuminated strobe, read directly off the rim of the platter.

 

 

Specifications

Drive:  Dual 8-pole synchornous motor; flat belt for flywheel drive

Starting Time:  approx. 2 sec. (33-⅓rpm)

Platter:  Non-Magnetic, dynamically balanced

Diameter :  305 mm

Weight :  1,3 kg ( platter with flywheel drive 2,1 kg)

Platter Speeds:  33-⅓ and 45 rpm. Automatic tonearm set-down coupled with speed adjustment

Pitch Control Variation:  Adjustment range of approx. 1semitone (approx 6%) at both platter speeds

Speed Control:  with illuminated stroboscope for platter speeds (33-⅓, 45 rpm)

Illuminated Strobe Sensitivity for Speed Deviation of 0,1% :

3,0 bars/min at 50 cps

3,6 bar/minn at 60 cps

Wow and Flutter:  According to DIN 45 507 (GIS < ±0,08%

Rumble (according to DIN 45 500):

Unweighted :  better than 42 dB

Weighted :  better than 63 dB

Tonearm:  torsion-resistant tubular aluminnum tonearm in four-point gimbal

Effective Length:  222 mm

Offset Angle:  25° 20'

Tangential Tracking Error:  0,16 °/cm

Tonearm Bearing Friction (related to stylus tip):

Vertical :  less than 0,07 mN (0,007 p)

Horizontal :  less than 0,16 mN (0,16 p)

Stylus Pressure:  0 - 30 mN (0 - 3 g) Infinitely variable with 1 mN (1/10 g), calibration from 0 - 15 mN (0 - 1,5 g) operable from 2,5 mN (0,25 g) stylus pressure up

Cartridge Holder:  Removable, accepting any cartridges with 1/2", mounting and weight from 4,5 to 10 g

Adjustable Overhang: 5 mm

Current:  AC 50 or 60 Hz, changeable by changing motor pulley

Line Voltage:  110 - 130 V 0r 220 - 240 V , switchable

Power Consumption:  approx. 10 Watts

Dimensions (W x H x D):  420 x 148 x 365 mm

Weight:  7,6 kg

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