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    Icon10 Amp Gain Matched To Head Unit Voltage

    How do i Match my amp's gain to my head unit voltage. I have a Alpine 9855 H/U and it has 3 4v preouts i have 2 alpine amps as well a, V12 Digital Mono Amplifier MRD-M605 for my subs which are 2 alpine 12 E-Type and a, 4 3/2 Channel V-Power Series Amplifier MRP-F240 for my inside speaker which are all alpine as well. I need to know how set the gain correctly. I dont hear the music till the volume on my H/U is 50% up and its real low i want to know if the gain has somthing to do with this delima







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    Re: Amp Gain Matched To Head Unit Voltage




    Quote Originally Posted by chase007 View Post
    if u need a box...I'l taked 3 years of shop class so i know what im doing.

    after i explained to him there's more to a proper box than boards and glue and he should practice before trying to sell boxes to others

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    yes personaly if it was some one elce that just starting making boxes but i'v taken shop for 3 years now...Making a lil box is nothing i don't need to pratice on a box to get it right i learned alot of stuff from 1 box and i can fix that in my next box
    after i told him that customers would care about the looks of the box

    Quote Originally Posted by chase007 View Post
    if u want some thing that looks pretty why don't u find a black guy with a big d*ck.

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    Re: Amp Gain Matched To Head Unit Voltage

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    Re: Amp Gain Matched To Head Unit Voltage

    by the way you will need a multimeter and the gain setting tutorial sticky



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    Re: Amp Gain Matched To Head Unit Voltage

    did the gain tutorial disappear?




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    Re: Amp Gain Matched To Head Unit Voltage

    lets hope so. every DMM based gain setting guide makes me want to stab someone in the eye...

    quick rundown
    1.) get a DMM with an AC voltmeter.
    2.) turn the HU to 3/4th to full volume.
    3.) turn off bass boost and EQ. disconnect speakers at the amplifier (not at the speaker). turn off lowpass and highpass filters.
    4.) determine how much AC Voltage should be on the outputs for a given power.
    V = (Power * Impedance)^0.5 (square root of the product of power and impedance.) see a wiring guide for multi-sub setups.
    5.) adjust the gain on the amp until this voltage appears on the DMM. measure AC voltage at the amp's output.
    6.) ok. use a marking device or a camera to mark or otherwise store these "optimal" gain settings. because the actual values will be different.

    7.) Ok, now turn the HU down. reattach the speakers. Set some crossover points, like Lowpass @ 80hz for woofers, and highpass @80hz for mids. listen to some music with complex bass lines. turn up the music a bit. adjust gains.

    likely you will have some speakers too loud. if the bass is too loud, turn down the gain on the sub amp. if the speakers distort, turn down the gain on the speaker amps.

    try doing this over a series of days. anytime you listen to loud music, you're ears will adjust to the levels in an odd way. if you take many short trips, this will become apparent. the settings you made after listening for an extended time will sound different when your ears are fresh...

    setting gains for optimal sound is a bit harder then setting gains for optimal power. almost every DMM based gain tutorial forgets that in liue of "hey, pretty numbers".



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