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GENERAL AMPLIFICATION NOTES & REQUIREMENTS
o
For the purpose of this discussion: Crown I_TECH 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).
o
Equivalent amplifiers can be used as substitutions.
o
Users should observe differences in input sensitivity and maximum available power at a given
impedance load.
o
Users may choose to use the same size amplifier to power all components / passbands.
o
DSP crossover presets provided by JBL assume that the same amplifier models with equal
voltage gain, are used for each bandpass.
o
If different gain settings or amplifiers models are used, users may need to adjust the output
gains of the digital controller(s).
VT4489
o 4 VT4889 can be powered with (4) I-T4000.
Two boxes are wired in parallel per NL8 circuit.
(HF: CH1 & CH2, MF: CH1 & CH2, LO1: CH1 & CH2, LO2: CH1 & CH2)
o Using (4) I-T6000 would provide enough power to drive up to 6 VT4889.
Three boxes are wired in parallel per NL8 circuit.
o I-T4000 can be used for the HF section to power 2 or 3 boxes.
VT4888
o 4 VT4888 can be powered with 4 I-T4000.
Two boxes are wired in parallel per NL8 circuit.
(HF: CH1 & CH2, MF: CH1 & CH2, LO1: CH1 & CH2, LO2: CH1 & CH2)
o Using 4 I-T6000 would provide enough power to drive up to 6 VT4888.
Three boxes are wired in parallel.
o I-T4000 can be used for the HF or MF section to power 2 or 3 boxes.
VT 4887
o 4 VT4887 can be powered with (1) I-T4000.
If four boxes are wired in parallel per NL8 circuit then
CH1: LF @ 2 ohms & CH2: MH/HF @ 2 ohms.
VT4880
o 2 VT4880 can be powered with (1) I-T4000.
If two boxes are wired in parallel using NL4 cables then each amp channel powers (4) 2258
for a 4 ohms load.
o 3 VT4880 can be powered with (1) I-T6000.
If three boxes are wired in parallel using NL4 cables then each amp channel powers (3)
2258 for a 2.7 ohms load.
o 4 VT4880 can be powered with (1) I-T8000.
If four boxes are wired in parallel using NL4 cables then each amp channel powers (4) 2258
for a 2.0 ohms load.
Separate NL4 cable runs are recommended with parallel wiring at the amp.
VT4881
o 4 VT4881 can be powered with (1) I-T4000.
If four boxes are wired in parallel using NL4 cables then each amp channel powers (4)
distinct coils of dual-coil 2256Gs for a 2.0 ohms load. Each 2256G has (2) coils.
Separate NL4 cable runs are recommended with parallel wiring at the amp.
