JAMO D 590, Руководство пользователя

Страница: 7 / 9

2
GB
INTRODUCTION
Congratulations on your choice of the Jamo D 5 series.
You now have a set of loudspeakers far above average for sound, quality, and finish.
You will no doubt be anxious to listen to the loudspeakers.
We do, however, recommend that, to benefit fully from your investment, you adhere meticulously to the instructions for connection and
placing.
DESIGN
CABINET
The most conspicuous feature of the D 570 and D 590 is their design. For one thing, this design offers a large cabinet without the
loudspeaker seeming big; it also damps “standing waves”. Further, owing to the rather considerable depth of the cabinet, the treble and
mid-range units are placed so far from the back wall as to prevent reflections.
The cabinet sides are made in a brand new sandwich design consisting of a MDF board with longitudinal grooves and an fibre board. After
grooving the MDF board, allowing for the arc-shape, the two boards are glued together resulting in an extremely rigid board poor in
resonance, preventing undesirable cabinet vibrations from “colouring” the sound.
The front grille consists of a thin MDF board frame, covered with fabric. The very close contact between loudspeaker and front frame,
together with the flat front frame, ensures that the diffraction (colouring/distortion particu-larly of upper midrange and treble, due to
reflections from the loudspeaker front irre-gularities), is reduced to a minimum.
DRIVE UNITS
The treble is a soft dome tweeter.
The unit is oil cooled and has a voice coil wound of thermosetting wire on an aluminium voice coil former, for high power handling.
The midrange units have a specially woven fibre glass diaphragm. Other than the exclusive design, the special weave ensures a uniform
material thickness over the entire diaphragm.
A loudspeaker diaphragm can be compared to a piston, and to comply with the heavy demands on the diaphragm material’s stretch and
compression properties, the composite fibre material is composed of four different types of glass and treated with a tough-hardening
resin. This results in a light and rigid cone with good internal damping. Combined with the natural rubber suspension, which ef-fectively
prevents vibrations from travelling back to the diaphragm, the result is a very well-controlled diaphragm that operates without break-ups
in its working range.
The unit’s basket is made in injection moulded carbon fibre reinforced ABS. Using a non-magnetic material such as ABS ensures that the
magnetic force stays concentrated around the voice coil instead of spreading out into the basket.
As a result, the efficiency of the unit is increased, and the loudspeaker may be placed closer to a TV set without risk of discolouring the
image. Compared to a conventional metal basket, the acoustic properties are significantly improved, as the ABS material has a much
higher internal damping.
The unit has a large magnet and a heavy voice coil with a diameter of 25mm.
All these properties lead to an open and precise sound reproduction with unsurpassed attack. As the design of the unit also makes for
very low distortion and excellent reproduction of a large frequency area, phase errors in the important midrange area can be eliminated,
since this entire area is reproduced by one single unit.
This principle has been used in the Jamo D 5 series, in which the midrange units cover the range from appr. 150 to 3,000 Hz. In D 570
/ D 590, two midrange units have been used to control the sound scatter, i.e.: for one thing, higher horizontal scatter, making the
listening position less critical, and also less vertical scatter, making fewer reflections from the floor and the ceiling.
The D 570 / D 590 has specially developed long-throw woofers mounted at the bottom of the cabinets.
This woofer placing ensures an excellent coupling to the room and thus a very smooth frequency response and an uncritical set up of the
speakers. Please also see the "Setup" section of this manual.