Robust, reliable and repeatable performance in application

A requirement for the BeoLab 5 was that it maintain high standards of consistency in operation, and require no particular maintenance. Also, it was felt to be necessary to be able to restore a BeoLab 5 to its original performance specifications in the field, in the event of any driver or electronic malfunction or failure. Because of the requirement for DSP and significant computational capacity in order to implement ABC, it was determined to manage all electronic adjustments in the digital realm, including “linear phase” crossovers, equalization and time correction for each driver, global equalization and assembly quality control.

This means that, in manufacture, each driver can be measured and its performance documented. During the quality control phase of manufacture, the loudspeaker is trimmed in the digital realm to a tolerance of +/- .25 dB in comparison with the reference BeoLab 5. The DSP manipulations needed to do this are recorded and archived, along with all of the driver values. An RS-232 port is available on each BeoLab 5, so that in the field, in the event that service is required, the loudspeaker can be restored to its original reference values. If a driver is replaced, the DSP is re-trimmed to bring that driver into compliance with the original specification.

There are two implications to this. First, each BeoLab 5 is matched to the reference unit to a tolerance that is effectively within the threshold of audibility for the various difference limens for amplitude change at frequency, which is to say that the differences between units are essentially inaudible. Second, the DSP block, coupled with appropriate documentation, makes it possible to maintain each BeoLab 5 to that specification as it ages. This is done without the need for intervention by the owner/user (other than to seek assistance), including diagnostics or adjustments.

In combination with the Adaptive Bass Control and the Acoustic Lens Technology, the BeoLab 5 stereophonic or surround arrays can be placed as needed and listened to from a wide range of positions with satisfactory and pleasurable timbral and musical results. No adjustments need to be undertaken by the end user.

Appropriate and functional appearance and build quality for a high quality “musical instrument.”

The appearance of the BeoLab 5 is based on the physical requirements of the acoustic lenses. From these, the final appearance has been determined, including a symbolic reference to the suspended cymbal with the brushed aluminum diffraction guide plates.

Conclusion

The BeoLab 5 represents an attempt to globally address the various issues presented by room interface at both high and low frequencies, power, reproducibility, and musical instrument gestalt in a single integrated loudspeaker system. Listening tests to date support its performance quality and ability to provide an significantly enhanced musical listening experience. The authors believe that, as a unique single design, the BeoLab 5 works more effectively in a wider range of listening rooms than any other loudspeaker designed to date.