User manual B&W CDM 9NT

[. . . ] Although many of these have been developed initially for the more expensive models, our "waterfall" design policy has seen them incorporated, wherever possible, elsewhere in the product range. Features to be found in the CDMTMNT Series include cabinets with contoured edges to reduce sound diffraction (the radiation of sound waves from sharp edges that interfere with and blur the direct sound from the drive units). an integral part of the CDMTM range is the use of Kevlar® cone bass/midrange drive units for lowest coloration and maximum definition. [. . . ] Always make sure terminals are screwed down tight as otherwise they may rattle. Keep the total impedance below the maximum recommended in specification and use a low inductance cable to avoid attenuation of the highest frequencies. If the level bass is uneven with frequency it is usually due to the excitation of resonance modes in the room. Even small changes in the position of the speakers or the listeners can have a profound effect on how these resonances affect the sound. Moving the speakers further from the walls will reduce the general level of bass. Space behind the speakers also helps to create an impression of depth. Conversely, moving the speakers closer to the walls will increase the level of bass. If you want to reduce the bass level without moving the speakers further from the wall, fit the foam bungs in the port tubes. (Figure 6) If the central image is poor, try moving the speakers closer together or toeing them in so they point just in front of the listeners. (Figure 5) If the sound is too harsh, increase the amount of soft furnishings in the room (for example us heavier curtains), or reduce it if the sound is dull and lifeless. Test for flutter echoes by clapping your hands and listening for rapid repetitions. Reduce them by the use of irregular shaped surfaces such as bookshelves and large pieces of furniture. Whenever possible fit the spike feet supplied after you have optimised the positioning. Initially, screw the lock nuts fully onto the spikes and screw the spikes fully into the threaded inserts in the base of the cabinet. If the cabinet rocks, unscrew the two spikes that do not touch the floor equally until the cabinet sits firmly on the floor, and lock the nuts against the cabinet. If there is no carpet and you wish to avoid scratching the floor surface, use a protective disc between the spike and the floor. (Figure 4) Some experimentation with the position of the speakers is well worthwhile to optimise the interaction between them and the listening room. however , as an initial guide: · Do not fit the spike feet until you have found the best position for the speakers. [. . . ] The grille fabric may be cleaned with a normal clothes brush whilst the grille is detached from the cabinet. Avoid touching the drive units, especially the tweeter, as damage may result. Before fine tuning, make sure that all the connections in the installation are correct and secure. [. . . ]