Item no. 69466 26.01 1 D 8SUB 2 D 8SUR D 8ADD Surround EX 4 3 D 8SUR 5 D 8CEN - a D 8CEN - b 6 4 Front D 8CEN Front D 8SUB Surround D 8SUR Surround D 8SUR Surround EX 7 5 Sub Line out D 8SUB 6 D 8SUB 8 7 8 www.jamospeakers.com 9 9 Type...............................................................D 8SUR System................................2 Way Bipole/Dipole Woofer......................................2 x 5¼ / 133 mm Tweeter............................................2 x 1 / 25 mm Power handling*........................150W / 200W Frequency range....................50 - 20.000 Hz Impedance................................................6 Ohm Dimensions........................272x256x194mm 10,7x10,1x7,6in Weight.........................................5,4 kg / 11,9 lb Type.............................................................D 8SUB System..........................Active subwoofer Woofer.............................................12 / 305 mm Amp. Rated output...............................400W Frequency range.............................28 - 120 Hz Upper cutoff frequency......Adj. 40 - 120 Hz Maximum SPL......................................107 dB Phase.................................Adjustable 0 - 180° Dimensions.......................407x454x454mm 16,0x17,9x17,9in Weight..........................................20,1 kg / 44,3 lb Type...........................................................D 8CEN Sytem....................3 Way Aperiodic Champer Woofer.......................................2 x 6½ / 165 mm Midrange..........................................1½ / 38 mm Tweeter..............................................1 / 25 mm Power handling*..........................110W / 150W Frequency range...................65 - 20.000 Hz Impedance................................................4 Ohm Dimensions..................217x555x285mm 8,5x21,9x11,2in Weight.........................................10,8 kg / 23,8 lb Specifications subject to technical changes. *Long / Short term power, According to IEC 268-5. 10 D 8ADD Advanced Owners Manual GB Congratulations on your choice of Jamo D 8. By choosing this high-end loudspeaker, you are ensured a first-rate natural sound reproduction - that is, of course, if the rest of your system can match the loudspeakers. For you will also be able to mercilessly reveal any possible shortcomings in the rest of the music chain as well as the music material used. In order to get the maximum benefit it is therefore important to go through these instructions which offer good advice about installing/ connecting the units and about the acoustics of the listening room. We also tell you a little about the techniques we have used and the decisions we have made to reach the goal - to present what it is all about - MUSIC! Introduction A few comments on quality To us at Jamo it is of fundamental importance that no Jamo loudspeaker is found to deviate from the reference model, irrespective of production time. In order to meet this requirement, all components and units must be approved within very narrow tolerances even at entry level. A continuous quality control is performed on all semi-manufactures, and in the end all Jamo loudspeakers are put through a compulsory final quality control before leaving the factory. Jamos consistent high levels of quality and workmanship, and thus the uniform quality in production, are based on several factors, notably the experience and expertise which have accumulated at Jamo since the companys start in 1968, as well as the fact that Jamo was the first loudspeaker manufacturer in the world to obtain certification according to the strict ISO 9001 quality norm in 1992. Unpacking When you unpack your new loudspeakers, you might think that the glow of the cabinets and/or the colour play of the veneer do not completely match the demonstration models that you may have seen at your Jamo dealers. However, this is just a result of the fact that each piece of genuine veneer will have its own individual features, and since it is a natural material, you will find that the colour play and the glow change as the loudspeakers are exposed to light and air. So in time they will look even better and have even more soul! Remember also that loudspeakers should be broken in, that is play for some time, before they can perform at their best! If you do not want to do this when you are at home, set your tuner between two stations, so that a hissing sound is heard from the loudspeakers. Then leave the loud-speakers to play for a few hours at a medium sound level. After this, the rest is up to you - we are sure that you will get many hours of fine entertainment. Enjoy yourself! Preben Jakobsen Julius Mortensen 2 GB Jamo D 8CEN was developed especially for the enthusiast who makes equally heavy demands on supreme and uncompromising reproduction of surround sound as for hi-fi listening. As the main job of the centre speaker is to reproduce the dialogue and the action taking place at the centre of the screen, we have given a high priority to obtaining optimum intelligibility of speech as well as powerful reproduction of the full frequency range in the Jamo D 8CEN. This means that all the sound reproduced by the centre loudspeaker will be clear and easy to understand - even at high sound pressures and when the dialogue is accompanied by loud explosions and other impressive sound effects in the film sound track. Design, D 8CEN Cabinet To obtain a dry reproduction of dialogue, a low resonance frequency is required - and usually a loudspeaker cabinet will do just the opposite - which is to increase the resonance frequency ! Impedance curve for a normal cabinet The effect of the cabinet on the resonance frequency We therefore used a special cabinet technology called Aperiodic Chamber for the Jamo D 8CEN. Impedance curve for an Aperiodic Chamber High resonance frequency Low resonance frequency Other than the dry reproduction, this technology also permits using large woofers in a relative small cabinet, resulting in the desired authoritative sound. Normally, using large woofers in small cabinets will result in a frequency overshoot immediately before the woofers low-frequency roll-off point. The consequence of this overshoot is very often perceived as a rumbling bass reproduction. Low freq. response in a normal cabinet (overshoot) The effect of the cabinet on the bass reproduction Therefore, the rear panel of an Aperiodic Chamber (cabinet) is ventilated through holes constituting around 20% of the woofers total diaphragm area. The ventilation results in an acoustic short-circuit of the lowest frequencies (it becomes effective around 200 Hz). Low freq. response in an Aperiodic Chamber (natural roll off) Ventilating the cabinet dampens the overshoot, partly because of the acoustical short-circuit, and partly because of the mechanical dampening applied to the woofers. In an Aperiodic Chamber, the diaphragm displacement will increase in the area below the resonance frequency - this means that although there is a low frequency short-circuit the frequency response will extend way below what is required of a centre loudspeaker. Of course the larger diaphragm displacement calls for customised woofers with well-controlled limits of displacement. Controlling the ventilation of an Aperiodic Chamber requires critical dampening with a large amount of acoustic absorption foam. This in combination with the reduced rear panel area minimises the formation of standing sound waves and thereby eliminates coloration/ distortion of the sound reproduction. The cabinet for the Jamo D 8CEN is manufactured in 25 mm MDF board with genuine veneer. The front baffle is a sandwich construction consisting of a strong die-cast synthetic shell and 22 mm MDF board. Tweeter and Midrange For the Jamo D 8CEN we have chosen a 1" and a 1½ soft dome to reproduce the treble and midrange areas, respectively. Both units are equipped with coated textile diaphragms and highly efficient neodymium magnets. The advantage of the compact size of the extremely powerful neodymium magnets is that they can be placed inside the voice coil. This ensures that a highly concentrated magnetic field is created exactly where it is needed. An additional advantage of this design is that the magnetic stray field is minimal, which eliminates the need for further magnetic shielding of these units. 3 GB The special 1½ midrange dome has been chosen to obtain a sufficiently low crossover frequency between the bass and midrange areas in order to ensure wide horizontal dispersion. This is important to enable the centre loudspeaker to cover a broad listening position, when several persons are listening. With a low crossover frequency, out of phase problems between the two woofers are avoided, allowing the required dispersion to be realised. In order to ensure perfect transition to the woofer, the midrange unit is fitted in a specially designed horn, which has been tuned to just below the resonant frequency of the unit. The horn provides a better coupling between the diaphragm and the surrounding air, which results in a linear reproduction and higher efficiency in the lower midrange area. Woofer The diaphragms of the two woofers are manufactured in fibre glass, which is a rigid and quite heavy material. The relatively heavy moving mass and the resulting low resonance frequency have been chosen partly to achieve optimum harmony with the Aperiodic Chamber and partly to obtain the desired powerful and precise reproduction of the bass area below 1000 Hz. The woofers frame is made in die-cast plastic. This ensures that the magnetic force stays concentrated around the voice coil instead of spreading out into the basket. Also the magnetic strayfield is perfectly controlled, so that the loudspeaker can be placed directly on top of a TV set without causing discoloration of the picture. Cabinet Design D 8SUR The most conspicuous feature about the Jamo D 8SUR loudspeaker set is the design. The unique design was developed not only to please the eye, but equally to satisfy the ear. Jamo D 8SUR is manufactured in 16 mm MDF board and accurately dampened with acoustic foam. The surface of the foam is shaped in a honeycomb pattern to obtain the largest possible surface area and thus maximum dampening of the sound radiating from the rear of the units. To achieve optimum sound reproduction, the designs of the two loudspeakers in a pair are laterally reversed and therefore they are available only in sets of a left and right loudspeaker (see the marking on the back of the loudspeakers). 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 woofer 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 materials 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 units basket is made from 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. Jamo D 8SUR is designed to enable a diffuse sound reproduction giving the listener the feeling of being enveloped in sound. In conventional loudspeakers, this type of design will usually lead to a lack of efficiency in the deep bass area. However, in order to meet the demands of digital 5.1 sound, Jamo D 8SUR is equipped with a filter to significantly improve the bass reproduction: at low frequencies, the loudspeaker acts as a traditional box with two woofer units working in phase, giving a bipolar characteristic. At high frequencies, the phase of the reproduction will gradually shift to give the loudspeaker a dipole characteristic. In other words, Jamo D 8SUR combines the best of these tw ...