JL Audio Slash 300/4v3 オーナーマニュアル

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8  |  JL Audio - 300/4
v3
 Owner’s Manual  
9
Fr
Bridged
Left
Right
Rear Speaker Outputs
Filte
Fre
x
n
h.
ns.
50
60
75
 
I M P O R TA N T
!
 
For optimum power output at all four channels, 
connect the same impedance (between 1.5-4Ω) 
on all four channels. On pages 16 and 17 are 
charts showing the continuous (RMS) power 
output capability of the 300/4v3 into various 
combinations of front and rear impedances 
(optimum output is shown in bold type). Please 
refer to these charts so you know what to expect 
in terms of power output.
 
I M P O R TA N T
!
 
 If you connect a load higher than 4Ω nominal 
per channel in stereo mode (or 8Ω in bridged 
mode), power will drop by half with every 
doubling of impedance above 4Ω stereo / 8Ω 
mono. If you connect a load lower than 1.5Ω 
nominal per channel in stereo mode (or 3Ω in 
bridged mode, the amplifier protection 
circuitry activates a “safe” mode which reduces 
amplifier power to protect the circuitry from 
failure (the yellow “Low Ω” LED  lights to 
indicate that this has happened). See page 10 
for details.
 
I M P O R TA N T
!
 
Speaker loads below 1.5Ω nominal per channel 
in stereo or 3Ω nominal in bridged mode are 
not recommended and may cause the amplifier 
output to distort excessively. 
 
BRIDGING CONSIDERATIONS
Bridging is the practice of combining the 
output of two amplifier channels to drive a single 
load. When bridged, each channel produces 
signals of equal magnitude, but opposite polarity. 
The combined output of the two channels 
provides twice the output voltage available from a 
single channel. The 300/4v3 has been designed for 
bridging of its channel pairs without the need for 
input inversion adaptors.
Bridged
Left
Right
Front Speaker Outputs
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 a mono signal to both left and right RCA inputs  
for that channel pair. This requires an RCA  
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When bridged, each channel pair will 
deliver optimum power into a 3-8Ω load. 
Operating bridged channel pairs into a load 
lower than 3Ω is not recommended. 
Because a bridged pair of channels requires 
that both channels receive input, you need to 
connect both left and right RCA inputs to the 
bridged channel pair’s inputs. Connection of 
only one RCA input will result in reduced power 
output, increased distortion and can cause the 
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left and right RCA inputs.
 
2) 
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allows you to select from two filter 
slopes for that channel section.
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frequencies above or below the selected 
filter frequency at a rate of 12 dB per octave 
(Butterworth alignment). 
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frequencies above or 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 
sound of different speakers in the system. 
Experiment to find the slope which best matches 
the acoustic requirements of the system. The 
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protecting small speakers with limited power 
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allows for greater energy overlap with the rest of 
the speaker system. In some cases, this results 
in better overall response and sound quality.
 
3) 
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the right, this switch multiplies the cutoff 
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(Hz)
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position, the range of the rotary control is  
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position, the range of the rotary control is  
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4) 
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markings surrounding this rotary control 
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 
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SPEAKER OUTPUTS
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amps in your day, please take the time to read this 
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care must be taken to balance the front and rear 
channel speaker impedances for optimum output 
from all four channels.
The 300/4v3 employs JL Audio’s exclusive 
Regulated, Intelligent Power Supply (R.I.P.S.) 
design. This sophisticated power supply allows 
the amplifier to produce its optimum power (300 
watts) over a wide range of speaker impedances. 
Unlike conventional amplifiers that require a 
specific impedance to produce optimum power, 
the R.I.P.S.-equipped 300/4v3 gives you the 
freedom to use a variety of speaker configurations 
that achieve final impedances between 1.5 – 4 
Ohms nominal per channel (without sacrificing 
power output or sound quality).
The operation of the R.I.P.S. circuitry is 
entirely automatic and adjusts itself every time 
the amplifier is turned on according to the 
lowest impedance present at either front or rear 
channels. There are no user controls to configure.
The system operates through three stages of 
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most appropriate to the actual impedance of the 
speakers connected to it. 
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supply, it will set itself up based on the lowest 
impedance present at either the front or rear 
amplifier channels. For example, if you connect 
a 2 ohm load to each front channel and a 4 ohm 
load to each rear channel, the amplifier will adjust 
itself to deliver 75 watts x 2 to the front 2 ohm 
loads, but will only deliver half its optimum power 
(37.5 watts x 2) to the rear 4 ohm loads. If you 
connect a 4 ohm load to all four channels or a 2 
ohm load to all four channels, the amplifier will 
deliver 75 watts x 4.  See, we told you this amp 
was different... Read on, there is more important 
information to follow.