I M P O Rta N T, Tri-Amplifiedsystems

TRI-AMPLIFIED SYSTEMS

Tri-amplified systems are defined as systems in which separate amplifier channels drive low-frequency (LF), mid-frequency (MF) and high-frequency (HF) speakers and are separately filtered to send appropriate frequency ranges to each speaker system.

The most common application of tri- amplification in mobile audio is to drive a subwoofer system from one or more amplifiers or channels (LF channels), mid-range speakers from a separate amplifier or set of channels (MF channels) and high-frequency speakers from a separate amplifier or set of channels (HF channels). One such configuration is to run subwoofers off the LF channel(s), mid- bass speakers off the MF channels, and a passively crossed over mid/high frequency component speaker systems on the HF channels. Another approach is to run subwoofers off the LF channel(s), mid-woofers off the MF channels and tweeters off the HF channels (all actively crossed over).

By activating the CH 1&2 bandpass filter feature, the 450/4v2 can easily be configured to drive a tri-amplified system in conjunction with a separate subwoofer amplifier that includes a low-pass filter. CH 3&4 of the 450/1 will drive the HF speakers (75W x 2), CH 1&2 will drive the MF speakers (150W x 2) and the separate subwoofer amp(s) will drive the LF speakers (subwoofers).

Input connection options for the Tri-Amplified Stereo mode are as follows:

A)No User Adjustability

Required: a basic source unit or processor with left and right stereo outputs.

Input Connections: a single pair of stereo source unit outputs is connected to the CH

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are connected to the preamp outputs of the

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Result: the relative level of all channels will be

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and will not be user adjustable from the front of the vehicle.

B)Fade Subwoofer Level vs. MF/HF Level Required: a source unit or processor with front

and rear pairs of outputs is required. Input Connections: one stereo pair of source

unit outputs is connected to the CH 1&2

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iInput ModewTXJUDIJOUIFiCH 1&2 Input Sectionw BOEUIFTFDPOETUFSFPQBJSPGTPVSDF unit outputs is connected to the subwoofer amplifier inputs. In this mode, the 450/4v2’s preamp output is not used.

Result: the user has the ability to adjust the level of the subwoofer channel relative to the mid and high-frequency channels via the source unit’s fader control, without exceeding the maximum clean output level set by each

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C)Subwoofer Level Control Only Required: a source unit or processor with left, right and dedicated subwoofer outputs is required.

Input Connections: one stereo pair of source unit outputs is connected to the CH 1&2

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iInput ModewTXJUDIJOUIFiCH 1&2 Input Sectionw BOEUIFTPVSDFVOJUTEFEJDBUFE subwoofer output is connected to the subwoofer amplifier inputs. In this mode, the 450/4v2’s preamp output is not used.

Result: the user has the ability to control the absolute level of the subwoofer channel relative to the MF and HF channels.

! I M P O RTA N T

Set the subwoofer amplifier’s “Input Sens.” with the source unit’s subwoofer level control set at 3/4 of full output. Refer to the subwoofer amplifier owner’s manual for proper adjustment.

Crossover setup for tri-amplified 3.1 system with one 450/4v2 and a separate subwoofer amplifier:

Once the input and preamp output sections have

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will determine the high-pass cutoff and slope of the bandpass filtering applied to the MF (mid-

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RangewTXJUDIiBPw CBOEQBTT POUIFiFilter

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cannot be used in this mode.

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the high-pass cutoff and slope of the high pass filtering applied to the HF (high-frequency) channels as well as the low-pass cutoff frequency and slope for the MF channels’ bandpass filter.

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desired MF to HF crossover frequency is below

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if your desired MF to HF crossover frequency

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After proper adjustment of the 450/4v2’s CH 1&2 and CH 3&4, and the subwoofer amplifier’s

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tune filter frequencies and slopes and attenuate the LF, MF and HF channel pair or with the

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controls of the 450/4v2 use the method shown in Appendix B (page 22). For precise filter frequency information for the 450/4v2 refer to Appendix A (page 22). Refer to the subwoofer amplifier owner’s manual for proper adjustments.

20 JL Audio - 450/4v2 Owner’s Manual

JL Audio 450/4V2 owner manual I M P O Rta N T, Tri-Amplifiedsystems, ANo User Adjustability

Models: 450/4V2

TRI-AMPLIFIED SYSTEMS

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TRI-AMPLIFIED SYSTEMS

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