Benefits of Line Arrays with More-Compact Speaker Units
1. Introduction We have developed a new VXL series of column-type line array speakers in order to further expand Yamaha’s lineup of speakers for commercial installations—which currently includes the VXS surface-mount series and VXC ceiling-mount series—and to also cater for a wider range of applications.
2. Three key features of VXL audio performance Key feature 1 Small speaker units More than anything else in developing the line-array speakers of the VXL series, we were resolute in our selection of smaller speaker units in order to optimize the distinguishing acoustic performance of the line array—namely, narrower vertical dispersion combined with wider horizontal dispersion—for the typical frequency range of speech. Based on an inventive redesign of the 1.
Turning our attention now to the horizontal plane, Figure 2 shows the wide dispersion* of 170° that can be achieved with small speaker units. Thanks to this, it is possible to reduce the number of arrays needed to provide coverage for the entire listening area, leading to fewer areas of interference, eliminating undesirable reverberation, and achieving clearer sound reinforcement of speech overall.
Key feature 2 Greater control of functional downward dispersion Given that line-array speakers leverage the characteristics of the line source to limit the spread of amplified sound in the vertical plane, installing these speakers relatively high off the ground can exclude the front-of-house from the coverage area, reducing volume and clarity. Typical remedies are the installation of separate subwoofers for this zone or using arrays with a J-shaped curve to increase downward dispersion.
Key feature 3 Mixing models for scalability In order to support a wide variety of diverse installations, the VXL series features three different array models—the VXL1-8, VXL1-16, and VXL1-24—each containing a different number of speaker units. Furthermore, complete arrays can also be combined and linked both horizontally and vertically for even greater scalability and flexibility in adjusting sound pressure and coverage area, in order to suit all kinds of installation environments and applications.
3. Conclusion As described above, our aim in developing the VXL series was to solve many of the problems faced in sound reinforcement with a lineup of column-type line-array speakers that deliver a clearer amplified sound, provide for high-quality music playback, are perfectly matched to a wide range of building architectures and interiors, and thereby, allow for a higher degree of freedom in the design of sound spaces.
Appendix Why is feedback less likely to occur with line-array speakers? Line-array speakers are commonly said to be less prone to audio feedback than point-source speakers, and the reason can be attributed to the coupling mechanism used with the individual speaker units, and the way in which volume attenuates over distance.
In order to better understand the conditions affecting the sound energy picked up by a microphone located near a speaker, let’s take a look at both a line-array speaker and a point-source speaker, assuming that the distances to the listening point and the sound-pressure level at that point are identical for each.
Point-source speaker (point source) Line-array speaker (line source) Sound-pressure level Sound-pressure level is lower near the line-array speaker. Attenuation over distance: -6 dB/DD Sound reinforcement to the same sound-pressure level at a specific distance.