Lexicon MC-12 manual 1KHz Reflected waves Direct waves 100Hz

Understanding Room Equalization Lexicon MC-12 Controller

1KHz

Reflected waves

Direct waves Reflected waves

100Hz

The low frequencies tend to behave in predictable ways because the bass wavelengths are larger than the typical objects in a room. The mid and high frequencies generally behave differently from room to room because the foot-by-foot or inch-by-inch details dif- fer dramatically from room to room. No two rooms have the same exact placement of chairs, tables, lamp shades, bookshelves or people.

Good speaker designers know that there are differences from one room to another and try to develop speaker systems that take advantage of the room. However, they do not know the specifics of your particular room; how big it is, the arrangement of the fur- niture, speaker placement and so on.

Designers can correct for some speaker characteristics. For exam- ple, a typical cone driver does not radiate all frequencies evenly in all directions. With a floorstanding speaker, designers know how far above the floor each driver in the speaker will be. With this knowl- edge, they can specify details such as how far from a wall or corner their speaker should be placed. However, they must still design to some typical room. Your room might be quite different from what is thought to be typical.

Getting good sound in your room requires that you try to avoid setting it up in a manner that will create problems the speaker designer could not anticipate. Following are some tips for arrang- ing your listening room for optimal enjoyment (see Figure 1-5):

•If the room is still under construction, you should try to avoid building large enclaves or rectangular cavities such as foyers, bay windows, stairway entrances, and so on. Such spaces res- onate specific frequencies and affect the sound quality within the room.

•Try not to place speakers in cabinets or build them into walls unless the manufacturer has specified them for such applica- tions.

•Speakers designed to be freestanding should be used that way; likewise, those designed to be set against a wall or in a corner should be used that way. Every close boundary wall provides a boost in the bass, so a speaker placed inappropriately with respect to the wall will produce either insufficient or excessive bass.

•Seats should be positioned away from walls and corners. Seating positions too close to one or more walls will be subject to bass increases.

1-4