L-Acoustics V-DOSC, Operator'S Manual

Page: 55 / 158

L-ACOUSTICS V-DOSC Manual Version 4 6/29/2005 Page 55 of 158
INFRA PRESET
The INFRA preset features a 60 Hz crossover between SB218 subwoofers and the V-DOSC low
section. Main benefits obtained using the INFRA preset include: improved low frequency impact from
the flown V-DOSC array, simplified time alignment since wavelengths are longer, and possible
subjective preference for the subwoofers when run from 60 Hz on down since they become more of
a delocalized effect. In addition, power resource simulations have shown that the INFRA preset
provides an excellent repartition of resources between sub, low and high sections.
The INFRA preset is intended for ground stacked sub flown V-DOSC configurations
(physically separated).
AUX SUB drive can be implemented using Input B / Output 6 or by using SB218 DELAY ARC 60 Hz
or SB218 LCR 60 Hz presets (subs with positive polarity).
INFRA PRESET: Align SB218 peak 1/dip1/peak 2 with V-DOSC low section
Figure 37: Infra preset time alignment procedure
4W PRESET
The 4W preset features an 80 Hz crossover between SB218 subwoofers and the V-DOSC low
section. 4W presets provide a flatter overall response contour that is considered more suitable for
classical music or speech reinforcement. Although the 80 Hz HPF for the V-DOSC low section does
not fully utilize V-DOSC low end resources, subjectively, the low end can sound “tighter” due to the
80 Hz crossover point (but this is a matter of personal taste and program material). Venue acoustics
can also be a factor in selecting between INFRA and 4W presets – in difficult, reverberant rooms,
experimentation between these two presets is suggested.
The 4W preset is intended for ground stacked sub flown V-DOSC configurations (physically
separated).
AUX SUB drive can be implemented using Input B / Output 6 or by using the SB218 DELAY ARC 80
Hz or SB218 LCR 80 Hz presets (subs with positive polarity).
4W PRESET: Align SB218 dip1/peak 2 with V-DOSC low section
Figure 38: 4W preset time alignment procedure