JBL VT4881, VT4888, VT4887, VT4880 manual General Amplification Notes & Requirements, VT4889

GENERAL AMPLIFICATION NOTES & REQUIREMENTS

•For the purpose of this discussion: Crown MA series amplifiers are used below. HF indicates High Frequency drivers, MF indicates Mid Frequency drivers, LF indicates Low Frequency drivers and VLF stands for Very Low Frequency drivers (subwoofers).

•Equivalent amplifiers can be used as substitutions.

•Users should observe differences in input sensitivity and maximum available power at a given impedance load.

•Users may choose to use the same size amplifier to power all components / passbands.

•DSP crossover presets provided by JBL assume that the same amplifier models with equal voltage gain, are used for each bandpass.

•If different gain settings or amplifiers models are used, users may need to adjust the output gains of the digital controller(s).

VT4889

•4 VT4889 can be powered with (4) MA-3600, although the MA-5002 is recommended. Two boxes are wired in parallel per NL8 circuit.

(HF: CH1 & CH2, MF: CH1 & CH2, LO1: CH1 & CH2, LO2: CH1 & CH2)

•Using MA-5002’s would provide enough power to drive up to 6 VT4889.

Three boxes are wired in parallel per NL8 circuit.

•MA-2402 or MA-3600 can be used for the HF section to power 2 or 3 boxes.

VT4888

•4 VT4888 can be powered with (4) MA-3600, although the MA-5002 is recommended. Two boxes are wired in parallel per NL8 circuit.

(HF: CH1 & CH2, MF: CH1 & CH2, LO1: CH1 & CH2, LO2: CH1 & CH2)

•Using MA-5002’s would provide enough power to drive up to 6 VT4888.

Three boxes are wired in parallel.

•MA-2402 or MA-3600 can be used for the HF section to power 2 or 3 boxes.

VT 4887

•4 VT4887 can be powered with one (1) MA-5002.

If four boxes are wired in parallel per NL8 circuit then

CH1: LF @ 2 ohms & CH2: MH/HF @ 2 ohms.

•MA-2402 or MA-3600 or MA-36x12 can be used if 2 boxes are wired in parallel instead.

VT4880

•2 VT4880 are usually wired to (1) MA-3600 or (1) MA-5002. If two boxes are wired in parallel using NL4 cables then

CH1: 2258 left, pin 1+ @ 4 ohms & CH2: 2258 right, pin 2+ @ 4 ohms.

•Up to 3 boxes could be wired in parallel with loads of 2.7 ohms per amp channel.

VT4881

•2 VT4881 are usually wired to (1) MA-3600 or (1) MA-5002. If two boxes are wired in parallel using NL8 cables then

CH1: 2256G coil 1, pin 1+ @ 4 ohms & CH2: 2256G coil 2, pin 2+ @ 4 ohms.

•Up to 3 boxes could be wired in parallel with loads of 2.7 ohms per amp channel.

•Make parallel connections at amplifier rack to minimize cable losses.

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