B&W electronics dm70 Instruction Manual Download Page 3

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Contents

1. General Description

2. The Listening Room

3. Installation — unpacking and connection

4. Installation — Siting

5. Ancillary equipment

6. Specification

Page

B&W electronics

Meadow Road • Worthing

England -BN11 2RX

Summary of Contents for dm70

Page 1: ...B W DM70 Instruction manual test certificate and guarantee...

Page 2: ...DM70 B W DM Trade mark of B W electronics...

Page 3: ...neral Description 2 The Listening Room 3 Installation unpacking and connection 4 Installation Siting 5 Ancillary equipment 6 Specification Page 2 3 5 10 12 13 B W electronics Meadow Road Worthing Engl...

Page 4: ...cking and assembling your loudspeakers each DM70 system excluding stands is packed in two cartons refer to section 3 of this booklet In common with all B W loudspeaker systems the DM70 is subjected to...

Page 5: ...n a square or rectangular room the latter is to be preferred as the room resonances known as eigentones occur at spaced frequencies and are therefore of lower amplitude The most pronounced eigentones...

Page 6: ...s bookshelves and other items of wall furniture also play an important role in these parts of the spectrum A room with insufficient soft furnishing will give a hard or steely tonal quality to middle a...

Page 7: ...remove the accessory bag tied to the rear of the power pack at the back of each cabinet This bag contains all necessary hardware and spares such as fuses The smaller packages should then be unpacked...

Page 8: ...stination e g European or America etc If after having made this check on mains supply it is necessary to adjust the mains voltage please refer to the above diagram and read the instructions regarding...

Page 9: ...t secure by screwing down to the cabinet through the hole in the rear of each 701 foot with the screws provided Connection UNDER NO CIRCUMSTANCES SHOULD THE 701 ELECTROSTATIC UNIT BE REMOVED WITH EITH...

Page 10: ...he sound should appear to emanate from a relatively small area between the loudspeak ers If the phasing is incorrect the image will be broader and spread across the area between the loudspeakers Comme...

Page 11: ...s shows that the mains supply is functioning If the neon does not light when the mains is connected the fuse should be checked A spare fuse is provided but repeated replacements should not be made and...

Page 12: ...of a pair of DM70 s and a pair of conventional Loudspeakers are illustrated in figure 3 Fig 3 Listening area shown hatched in A simple guide to siting 1 It is suggested that in initial layout a flexi...

Page 13: ...n even and solid stereo image 4 The final point for consideration is whether to place the loud speakers parallel with the wall or surface or to angle them towards the listening area The governing fact...

Page 14: ...fier will depend on the size of your listening room on the preferred listening level as well as on the sensitivity of the loudspeakers True RMS outputs of between 25 and 100 watts per channel will mee...

Page 15: ...g a free air resonance of approximately 28 Hz The cone is formed from long fibre paper material with mass adjustment and damping to discourage cone break up provided by critically positioned rectangul...

Page 16: ...afely housed in a steel case The mains lead is captive for safety Cabinet The cabinet is constructed of 25mm chip board in the case of the Continental version the curved front formed from 19mm plywood...

Page 17: ...eight Weight with stand 45 4kg 100 lbs Standard Overall Height on Stand 31 i 808 mm Overall Width 3 2 815 mm Overall Depth 15 382 mm Continental Overall Height on Stand 32 s 820 mm Overall Width 26 s...

Page 18: ...Chamber B K equipment used throughout with type 4133 microphone at 1 metre Crossover and Filter Unit Individual Acoustic output from each Drive Unit showing Crossover frequency Polar Distribution 3 dB...

Page 19: ...4 ohms 20 Hz to 9 k Hz the impedance minimum occurring in a frequency region of very low music energy Plot of impedance of production sample of DM70 Distortion Harmonic analysis plotted against freque...

Page 20: ...ervals in ou Research Anechoic Chamber Microphone type B K 4133 31 5 Hz 40 Hz 50 Hz 63 Hz 80 Hz 100 Hz 125 Hz 160 Hz 200 Hz 250 Hz 315 Hz 400 Hz 500 Hz 630 Hz 800 Hz 1kHz 1 25 kHz 1 6 kHz 2 0 kHz 2 5...

Page 21: ...Polar response 100 Hz Polar response 1 k Hz Polar response 10 k Hz Polar response R k H 19...