JL Audio 450/4V2 I M P O Rta N T, Crossover Controls, a given input voltage when the “Input

! I M P O RTA N T

CROSSOVER CONTROLS CH 3&4 Filter Section:

The output of the amplifier will decrease for	Crossovers are groups of individual electronic	2) iFilter Mode/Slopew $POUSPM 5IJT TXJUDI		CH 3 & 4 Filter Section			CH
a given input voltage when the “Input	filters which allow only certain frequency	allows you to defeat the CH 1&2 filter or select
				Freq. Range High-Pass Filter			Inpu
Range” switch is placed in the “High”	ranges to pass through them by attenuating	from two filter slopes.
position. Conversely, the output will be	frequencies outside the selected range. These			x1 x10	Off 12dB 24dB		Low
higher with the switch in the “Low” position.	filters allow the user to specify what frequency	iOffw %FGFBUT UIF GJMUFS GPS $)  DPNQMFUFMZ	Mode	95	130	low-pass
				75
						Also sets
While this may sound counter-intuitive, it is	range will be sent out of each channel section	allowing the full range of frequencies present		60	200	cutoff for
						Bandpass
						CH 1 & 2
correct as described.	of the amplifier. This, in turn, allows each	at the inputs to feed that pair of channels.	4ch	50	500	Filter
			1 & 2			(if selected)
	speaker system to only reproduce a range of	5IJT JT VTFGVM GPS TZTUFNT VUJMJ[JOH PVUCPBSE	and HP Filter Freq. (Hz)				(
			3 & 4
3) Input Sensitivity Adjustment: Located next	frequencies it is well-suited for, resulting in	crossovers or requiring full-range reproduction
UP UIF iInput Voltagew TXJUDI JO FBDI JOQVU	reduced distortion and improved fidelity.	from that pair of channels.
TFDUJPO JT B SPUBSZ DPOUSPM MBCFMFE iInput			1) i High-Pass Filterw $POUSPM 5IJT TXJUDI BMMPXT
Sens.w 0ODF UIF BQQSPQSJBUF iInput Voltagew	CH 1&2 Filter Section:	i 12dBw $POGJHVSFT UIF GJMUFS GPS $) 	you to defeat the CH 3&4 filter or select from

range has been selected, this control can be	trol	CH 1 & 2 Filter Section			to attenuate frequencies above or below the
used to match the source unit’s output voltage					selected filter frequency at a rate of 12 dB per
	c Filter	Freq. Range Filter Mode Slope		Input V
to the input stage of each pair of amplifier					octave (Butterworth alignment).
channels for maximum clean output. Rotating	0Hz	x1 x10	Off 12dB 24dB	Low
the control clockwise will result in higher	e	95	130 Filter Type		i 24dBw $POGJHVSFT UIF GJMUFS GPS $) 
		75
	r
sensitivity (louder for a given input voltage).	he	60	200		to attenuate frequencies above or below the
	to
	nput
Rotating the control counter-clockwise will	hen	50	500 LP BP HP		selected filter frequency at a rate of 24 dB per
	ed.
		Filter Freq. (Hz)		CH
result in lower sensitivity (quieter for a given				(Le	PDUBWF -JOLXJU[3JMFZ BMJHONFOU 
input voltage). To properly set each pair
of amplifier channels for maximum clean	1) iFilter Typew $POUSPM -PDBUFE JO UIF				%FQFOEJOH PO UIF TQFBLFS TZTUFN BOE
output, please refer to Appendix B (page 22)	iCH 1&2 Filter Sectionw UIJT TXJUDI BMMPXT				the vehicle, different filter slopes may be
in this manual. After using this procedure,	you to configure the CH 1&2 filter into one				required to produce a smooth transition
you can then adjust the relative level of each	of three filter types:				between the sound of different speakers in the
channel pair by adjusting the input sensitivity					system. Experiment to find the slope which
downward on either or both channel pairs, if	iLPw Low-Pass): Configures the CH 1&2				best matches the acoustic requirements of
they require attenuation to achieve the desired	filter to attenuate frequencies above				UIF TZTUFN 5IF TIBSQFS i24dBw TFUUJOH XJMM
TZTUFN CBMBODF %P OPU JODSFBTF UIF iInput	the selected filter frequency. Useful				do a better job of protecting small speakers
Sens.w TFUUJOH GPS BOZ BNQMJGJFS JO UIF TZTUFN	for connection of subwoofer(s) to CH				with limited power handling. The shallower
beyond the maximum level established during	1&2 in a bi-amplified system.				i12dBw PDUBWF TFUUJOH BMMPXT UIF SFBS TQFBLFST
the procedure outlined in Appendix B (page					to reproduce more low-frequency content.

  %PJOH TP XJMM SFTVMU JO BVEJCMF EJTUPSUJPO	iBPw #BOEQBTT  $POGJHVSFT UIF GJMUFS UP
and possible speaker damage. Be aware that	attenuate frequencies above the selected filter	3) iFreq. RangFw $POUSPM 8IFO UISPXO UP
CPUI iInput Sens.w BEKVTUNFOUT XJMM IBWF UP CF	frequency and below the frequency selected	the right, this switch multiplies the cutoff
made, regardless of how many input cables are	in the CH 3&4 High-Pass Filter. This creates	GSFRVFODZ TFMFDUFE CZ UIF SPUBSZ iFilter Freq.
feeding the amplifier. These controls will allow	a true bandpass filter well-suited for driving	(Hz)w DPOUSPM CZ B GBDUPS PG  *O UIF ix1w
you to set the appropriate relative levels for CH	mid-bass or mid-range speakers in a tri-	position, the range of the rotary control is
1&2 relative to CH 3&4 and other amplifier	amplified system.	   )[ BT NBSLFE  *O UIF ix10w
channels in the system.		position, the range of the rotary control is
	i HPw High-Pass): Configures the CH 1&2	 )[   L)[  )[ 
	filter to attenuate frequencies below the
	selected filter frequency. Useful for connection	4) iFilter Freq. (Hz)w 5IF GJMUFS GSFRVFODZ
	of component speakers to CH 1&2 in a bi-	markings surrounding this rotary control
	amplified system.	are for reference purposes and are generally
		accurate to within 1/3 octave or better. If you
		would like to select the filter cutoff frequency
		with a higher level of precision, consult the
		charts in Appendix A (page 22) of this manual.

two different filter slopes.

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allowing the full range of frequencies present at the inputs to feed that pair of channels.

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crossovers or requiring full-range reproduction from these channels.

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3&4 to attenuate frequencies below the selected filter frequency at a rate of 12 dB per octave (Butterworth alignment).

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3&4 to attenuate frequencies below the selected filter frequency at a rate of 24 dB per octave

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vehicle, different filter slopes may be required to produce a smooth transition between the speakers in the system. Experiment to find the slope which best matches the acoustic requirements

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will do a better job of protecting small speakers with limited power handling. The shallower

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reproduce more low-frequency content.

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right, this switch multiplies the cutoff frequency

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8 JL Audio - 450/4v2 Owner’s Manual 9