Celestion Ditton 15XR

 The completely new Ditton 15XR is a sophisticated bookshelf loudspeaker system using all new components but drawing on the valuable experience gained with the world renowed Ditton 15. the design of "compact" or bookshelf loudspeakers demands the solution of special problems if proper bass reproduction is to be obtained. With the introduction of the highly successful Ditton 15, Celestion perfected a principle now universally known as the ABR. This device has a rigid diaphragm with linear roll neoprene suspension. Its motional mass is precisely calculated and acoustically coupled within the hermetically sealed enclosure. When signals are applied to the main bass drive unit the tuning is such that the ABR is in phase through a frequency band in the region of 60 Hz down to 30 Hz. Bass frequencies are thus shared between the main and auxiliaty diaphragms.

 That the ABR confers substantial benefits perticularly where the enclosure dimensions have been limited, as in the Ditton 15XR, has been endorsed repeatedly by the technical Press. In addition to extending bass response downwards, giving a more realistic musical balance, and intrinsic function of the ABR is to reduce the required excursion of the main bass unit, thereby further reducing harmonic and doppler distortion. Both power handling and efficiency are also improved, resulting in increased dynamic range and therefore greater musical realism.

1. The latest type HD 1000 tweeter designed and produced by Celestion to the highest standards, the frequency range of this unit is from 2,5 kHz to 28 kHz. The domed diaphragm ensures good dispersion and low distortion.

2. Anechoic cellular foam wedge and lining absorbs unwanted acoustic energy within the enclosure and prevents the formation of standing waves which would be detrimental to the loudspeaker performance.

3. New NS8 (8") bass midrange drive unit with specially plasticized fibre cone to prevent resonsnces whilst the neoprene roll front suspension and concentric rear suspension permits the 1-inch long coil the large movements essential for the correct reproduction of low bass notes, with minimal distortion. A powerful 51,000 Maxwells (11,000 Gauss) magnet system weighing 1,1 kg controls these excursions, and all the components are housed in a new pressed steel plated chassis.

4. Units mounted flush to eliminate diffraction effects and tunnel resonances; covered by acoustically transparent grille cloth for maximum presence.

5. ABR (Auxiliary Bass Radiator) New 8" unit with front neoprene roll suspension and pressed steel plated chassis, developed to work in concert with the bass/midrange unit. 

Specifications

Power Ratings:

Maximum Rated Power:  60 watts programme (without clipping)

Continuous Sine Wave Voltage Rating

9,7 volts RMS max. 30 Hz - 2,6 kHz

7,0 volts RMS max. 2,6 kHz - 20 kHz

Sensitivity:  5,1 watts pink noise input produces 90 dB SPL at one metre in anechoic conditions

Amplifier Requirements:  10 - 60 watts RMS

Frequency response:

Overall :  30 Hz - 2 kHz

Specific:  60 Hz - 20 kHz ±4 dB;  45 Hz - 26 kHz +4 dB  -10 dB

Impedance:  8 Ω

Harmonic Distortion (at 90 dB SPL):

1,2% at 100 Hz

0,69% at 400 Hz

0,86% at 1 kHz

0,46% at 4 kHz

1,13% at 10 kHz

0,91% at 15 kHz

Crossover Frequencies:  2,4 kHz

System Resonance:  35 kHz

Internal Volume:  23 liters

Dimensions (H x W x D):  560 x 250 x 240 mm (22" x 9-3/2" x 9-1/2")

Finishes:  Teak or Walnt