Flown Subwoofers - L-Acoustics dV-DOSC Operator's Manual

♦ Use a LCR sub array configuration with the L,R arrays oriented at 45 degrees offstage. This can
give excellent results in terms of horizontal evenness provided that the same number of subs are
used for L, C, and R systems.
NOTE: Always time align and check the polarity of the subwoofer section to optimize low frequency
performance.
NOTE: For ground stacked subwoofer systems, typically an 80 Hz low pass filter is employed (with or
without aux sub drive). Presets for use with the SB218 are dV 3WX SB218 L0/HI (XTA) and DV 3WX SB
L/H (BSS). Presets for use with dV-SUB are dV 3W 80 dVS LO/HI (XTA) and DV 3W 80 L/H (BSS)

Flown Subwoofers

The benefits of flown subwoofers include:
♦ Improved low frequency summation when subs are flown close to the dV-DOSC arrays since the
subwoofers act as an extension of the system
♦ Due to longer wavelengths at low frequencies, floor coupling is still obtained with flown
subwoofers. Reductions due to lack of floor coupling are offset by reduced audience absorption
plus the reduction of subwoofer energy for the first 20 metres is largely due to the vertical
directivity that is introduced by vertically line arraying subs.
♦ Time alignment of subwoofers to the main left/right dV-DOSC arrays is greatly simplified since
the physical path length difference problem of ground stacked subs versus flown dV-DOSC is no
longer a factor that varies with listening position. Overall, this improves low frequency
summation and coherency for the entire audience.
♦ Elimination of local low frequency buildup for the audience down front in the first few rows.
Adding several ground stacked subs per side or a center line will provide sufficient low end
impact for the first 20 metres
♦ Cleaner staging and better sightlines.
NOTE: When subwoofers are flown and closely coupled to the dV-DOSC array, presets for use with the
SB218 are dV 3W SB218 L0/HI (XTA) and DV 3W SB L/H (BSS). Presets for use with dV-SUB are dV 3W
120 dVS LO/HI or dV 3W 200 dVS LO/HI (XTA) and DV 3W 120 L/H or DV 3W 200 L/H (BSS). The 80
Hz presets can also be used but the 120 Hz preset is considered optimal in terms of power bandwidth.
NOTE: 200 Hz presets should not be used for flown coplanar configurations (dV-SUB arrays flown on either
side of the dV-DOSC array) since WST Criterion #2 will not be satisfied.
dV-DOSC dV-SUB Manual V2.0 Nov 2001 67