EAW Three-way Loudspeakers manual C U R a T E W I D E B a N D D I R E C T I V I T Y

vocal region and give dialog exceptional warmth and clarity, EAW always employs cone drivers for its mid frequency subsystems.

sound effects. It also permits a greater degree of passive fil- tering to smooth the total system’s frequency response with- out sacrificing peak output.

2-way w/ compression driven high frequency

distortioncomfort

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Since three-way design divides the audio spectrum between three subsystems, each only needs to cover a little over three octaves – a range over which each driver can be truly optimized. The high frequency compression driver now operates only in the true high frequency range, mean- ing better performance in the very high frequency range. Similarly, optimized woofers can better handle the low fre- quency sound effects that give films that “digital sound.”

3-way w/ compression driven midrange

distortion comfort

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		Frequency (Hz)

T H R E E - W A Y I M P R O V E S O U T P U T

The maximum volume (peak output) that a loudspeaker sys- tem can generate is related to two factors: sensitivity (output generated by 1 Watt of power as measured at 1 meter) and power handling (the amount of power a loudspeaker can bear before failure).

Horn-loaded compression drivers enjoy excellent sensi- tivity characteristics but handle relatively low amounts of amplifier power, particularly when driven at very low fre- quencies (i.e. 500 Hz). By comparison, a horn-loaded, heavy-duty cone driver is somewhat less sensitive but han- dles substantially more power. The calculated peak output of the cone driven subsystem will be 6 - 10 dB higher than that of an equivalent compression driven subsystem. Higher peak output gives loudspeakers a greater dynamic range throughout the audio spectrum, which particularly improves reproduction of full range musical scores and

A C C U R A T E W I D E B A N D D I R E C T I V I T Y

The ability to put sound where it is needed and keep sound away from where it is not wanted distinguishes well- designed loudspeakers. When a loudspeaker with poor directivity characteristics sends some frequencies at wide angles and others at narrow angles, listeners at the edges of its coverage area will hear some frequencies and not others. Furthermore, uncontrolled soundwaves reflecting off walls and ceilings can create unacceptable reverberations that degrade the sound quality in the entire venue.

The directivity characteristics of a loudspeaker can vary widely depending on the frequency and the size of the sound producing device. The rule of thumb goes as follows: as the length of a sound wave decreases (with rising frequen- cy) to approach the size of the driver cone or horn mouth, directivity narrows; as the sound wave becomes smaller than the size of the driver or horn mouth, directivity becomes too narrow for most applications including cinema. The lower the frequency, the more difficult it is to confine to a narrow angle; the higher the frequency, the more difficult it is to dis- perse at a wide angle.

Traditional two-way cinema loudspeaker design uses an exceptionally large high frequency horn to provide pattern control at 500 Hz (which it does admirably). But making very high frequency sound waves “fill the bell” of the horn requires an exceptionally long horn throat. So long, in fact, that cancellation effects within the horn throat cause signifi- cant, audible distortion in the 700 Hz region. Smaller for- mat high frequency horns one encounters for smaller cine- mas produce much less distortion, but lack the necessary pattern control at 500 Hz.

By asking each subsystem to cover a smaller range than two-way designs, three-way loudspeakers can control both mid and high frequencies without introducing distortion. EAW’s larger three-way cinema designs – CB223 and MC4972 – employ smaller format high frequency horns with very short throats. Since they don’t need to control sounds in the 500 Hz range, their size is quite manageable. These horns disperse the highest frequencies across a wide area without noticeable distortion. Our smallest three-way cinema system, CB150, loads a compression driver on our shallow, throatless Wave Guide Plate™ giving high frequen- cies an exceptionally smooth character.

EAW’s proprietary manufacturing techniques allows us to produce the most mathematically accurate mid frequency horns in the industry. Automated saws and routers cut grooves in the enclosure that accept a flexible hardwood veneer shell which acts as a form for structural foam which we inject into the enclosure. The foam/veneer horn provides much greater rigidity than fiberglass horns, allowing it to control mid frequency sound waves with greater ease.

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