BBE DS48 - Manual (Page 7)

1
WHAT IS A SPEAKER MANAGEMENT SYSTEM?
A Speaker Management System uses digital signal processing to accom-
plish multiple functions that affect the audio signal between the mixer and
the power amplifiers. These functions include crossover, equalization,
delay, limiting, high-pass and low-pass filtering as well as signal distribu-
tion. Programs may be created, selected and edited with the DS48's front
panel controls. However, to create new programs, it is best to use the
included free PC software and configure the programs using the graphical
user interface (GUI) and a Windows PC.
2.1 Crossover:
This function uses filters to divide the audio spectrum into multiple bands, such as Highs,
Mids, and Lows. When these separate signals are individually amplified and sent to a
speaker matched for that range, the result is a much more efficient system with more
punch and clarity as compared to system using a two or three-way speaker box with a
passive cross-over. The common terms used for two or three-way systems are "bi-amp"
and "tri-amp".
2.2 Equalization:
This function provides control of the tonal spectrum. It can be used to compensate for dif-
fering acoustic conditions, speaker cabinet responses or boosting/cutting certain frequen-
cy ranges to create a specific type of sound. In some rooms, "ringing" or feedback is
present due to a number of conditions. Use the PEQ function to reduce the ringing fre-
quencies.
2.3 Delay:
This function is used to "time-align" the different transducers in a speaker system. A
properly aligned system will have better phase coherence resulting in more focused
sound.
2.4 High Pass and Low Pass Filters:
These are used to reduce any signal outside of the desired bandwidth and are part of the
equalization function. This frees the power amps and speakers from trying to reproduce
signals that are not an intended part of the mix or simply beyond the reproduction range
of the loudspeakers.
2.5 Limiting:
This function prevents a signal from exceeding a certain pre-determined level. It prevents
input overload with its resultant distortion and also keeps amplifiers from clipping, which
protects the speakers.
2.6 Signal Distribution:
This allows the signals from each of the four inputs to be processed and sent to the cor-
responding output. The crossover function is not active when in this mode. An LCRS (Left,
Center, Right, SUB) mode is also available.