The DM4 was
released at the International Audio Fair, October 1972 in the firm belief that
the design aims have been achieved, and from extensive comparasion with other
systems currently available we believe the DM4 may well out-perform competitive
loudspeaker systems of three times the size and twice the price.
The DM4 is a
3-unit loudspeaker comprising highly developed Bextrene coned Bass/Mid-range
unit (designed and produced in our own factory), type HF1300 Mk II lower high
frequency unit and a 19 mm plastic domed upper high frequency unit. Third
oreder Butterworth filters are used throughout and the crossover unit closely
integrates the optimum performance of the three units to give an exceptionally
smooth response extending from 30 Hz to above 25 kHz.
The DM4
monitor is individually pen tested in anechoic chamber and supplied with
automatic pen plot showing frequency response.
Stand-mount/Bookshelf
loudspeaker system
Product
Summary
The DM4 is a
three-unit monitor loudspeaker system that produces high quality results from
an incredibly small cabinet, making it perfect for home or small studio where
space is at a premium. Acoustic loading is by a very dense, critically damped
enclosure with a small controlling vent to optimise the response between 60 and
120 Hz. This also produces considerably reduction in cone excursion from 30 to
60 Hz.
Technical
highlights
The
bass/midrange units come in a critically contoured Bextrene cone configuration.
This is laminated in a highly resistant damping compound that ensures linear
frequency response to at least an octave above crossover.
The upper
mid frequency unit offers wide dispersion from a virtual point source and a
19mm low diaphragm mass plastic dome unit extends frequency response to above
25 kHz
Cabinet
Constructed
of 19 mm 750 density chipboard throughout with inside balancing veneers. All battens pinned and glued ,
Choice of teak, Walnut or Rosewood veneers plus a satin white finish.
Specifications
Drive Units:
High Frequency : 1 x 19 mm voice coil
Mid Frequency : 1 x 34 mm mid/high
frequency unit
Low Frequency : 1 x 164 mm
bass/midrange unit
Frequency Response: 30 Hz – 25 kHz. Better than ±
2dB,
Sensitivity:
4,8
watts into nominal impedance (i.e 6.2
volts) for a sound pressure of 95 dB pink noise at 1 metre
Nominal Impedance: 8 Ω
Power
Handling: 10 W – 30 W
Dimensions
(H x W x D): 531 x 255 x 255 mm
(21" x 10" x 10")
Weight: 11,1 kg (24 lb 6 oz)
Finish
Standard: teak or walnut