JBL and Crown have established this set of recommended circuiting configurations for all VerTec/iTechHD systems worldwide.
Please follow these good/better/best guidelines in order to ensure optimum system performance.
High Performance
A High Performance (HP) system has the following characteristics:
• 1:1 Ratio of Tops to Subs
• NO sub or LF section loads below 4ohms
• 2 cabinets per circuit for optimal array shading and tapering resolution
• Best possible power match to iTechHD amplifiers, with most systemwide headroom for loud concerts and highly dynamic
content.
Nominal
A Nominal (Nom) system has the following characteristics:
• 3:2 Ratio of Tops to Subs
• Some driver loads at 2.7ohms
• 3 cabinets per circuit for good match between power handling and array shading and tapering resolution
• Appropriate power match for iTechHD amplifiers, good balance between systemwide headroom and increased array
coverage
Economy Power
An Economy Power (Econ) system has the following characteristics:
• 2:1 Ratio of Tops to Subs, or no subs
• Some driver loads at 2ohms
• Using 3-Way+3-Way mode which powers lows at 2ohms on a circuit of 2 x VT4889 or VT4888
• Economy mode is appropriate for speech or music reinforcement with limited SPL requirements.
Operation Manual
page 26
page 27
Operation Manual
Output Panel
NOTE: Each subwoofer output is wired with the conductors in parallel: 1+/2+ and
1-/2-
NOTE Center NL8 connector (1/2 ch.1-2) LF sections are wired discreetly
. Max: 4x4889, 4x4888 (2ohm LF section load). Rec’d: 3x4889, 3x4888 (2.7ohm LF section load).
NOTE: Outside NL8 connectors (1/2/3 ch.1 & 1/2/3 ch.2) have pins 3+/- and 4+/-
wired in parallel. When using these connectors, max 2x4889 or 2x4888 (2ohm LF section load).
Output Wiring Modes
Summary of Contents for VRACK
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