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    amp settings? wiring questions

    Hi!

    Wrapping up the first audio job I've ever tried, replacing all the sound system on my 1990 colony park wagon.

    Just before I hook everything up:
    how do the settings on an amplifier work?

    It has five channels (4 stock speakers + my sub), it says it's good for 1200 watts.

    My front speakers are good for 45watts RMS, my rear speakers are only good for 40watts RMS (~135 peak for both, I think). I don't actually like my music very loud: even with the stock system I kept it to 1/8 full volume.

    I need to look up what the sub can take; it's a 10" made by kicker, and is 5 years old.

    I was looking for some peak wattage setting on the amp, but it doesn't exist: how do I make sure that I don't blow out my speakers? Is there a way to limit the output of the amp to a certain amount, so that my front speakers never do get more than say 120 watts to be safe?

    And, there are channels for frequency cutoffs... my front speakers are respectable but not terribly pricey 5.25" polks, coaxial (one tweeter each). My rear 6x9s are super cheap insignia branded (best buy's house brand?), that are 4-way: 2 tiny tweeters, 1 larger center tweeter, then the main speaker. I sit in the front, and the sub should take care of my bass: saw no need to splurge on the rear speakers. Anything was better than the paper-coned factory originals, my they were pathetic!
    And of course, the sub.

    How should I rig the frequencies sent to each speaker?



    I was curious about several other things, too.
    I assume this is all 12V. Now, best buy was going to sell me a $100 wiring kit made by kicker, came with a 4 gauge cable that the package claimed was good for 1000 watts (83 amps). Fascinatingly, the fuse that came with it says it's rated for only 30 amps! So I'd only get 360 watts to my 1200 watt amplifier. Not that I need my music very loud: but still, you see how this doesn't quite add up?
    Home depot btw would agree with the fuse, and not with the optimistic 1000 watt rating: their 4 gauge copper cabling I think is 40 amps, not 83.

    The best buy kit was expensive, and actually too short to run to the back of my wagon; so I bought 2 gauge wire at home depot. But I'll probably still put a 30 or 40 amp fuse on it. If I REALLY need it loud I can always get a heavier fuse in the future after this one burns!


    I was also puzzled by the presence on the harness of TWO dimmer wires, the dimmer ground (should I wire that into the regular ground?), and --oddly-- an amp turn-on wire, already there, disappearing into the dash! Is there an external amp already in the stock sound system, that I don't know about...?

    #2
    set high pass to the 4 speakers to around 150hz to start and see how that sounds. set the low pass on the sub to about 160hz (if it'll go that high) for some overlap to help fill in any gaps. Generally you want to overlap the frequencies by at least 10hz IIRC to account for the non-precision parts that most aftermarket stuff uses. If you don't like it loud... keep the gain knobs half or lower. This will help limit the power output to the speakers as well.

    Basically you'll just need to go for sound. Put the head unit at a volume level you think you'll use most and tune everything to that. Personal preference is the key here.

    as far as the wire gauge rating... check the nominal or RMS rating on the amp. That's probably what the fuse is rated for. The peak value is what the amp can discharge over a very short period of time. It's not really a good value to go by and mainly only good in bragging rights among kids as far as I'm concerned.

    I would match the in-line fuse on the installed wire to the fuse on the unit itself.

    the rest I'm not real sure about.

    Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
    rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
    Originally posted by gadget73
    ... and it should all work like magic and unicorns and stuff.
    Originally posted by dmccaig
    Overhead, some poor bastards are flying in airplanes.

    Comment


      #3
      There is no wattage setting on the amp. about all you should have are input level controls, usually marked 5v - 1v. This should be set to whatever the voltage level of your radio's outputs are. Many are now 5v, so you set the level to 5v. Wattage out is controlled entirely by the volume knob.

      For frequency, its going to depend on the amp itself. Commonly you'll have a high pass, low pass, or full frequency setting. The sub you want the low pass switched on. If it has adjustable crossover frequency, try it maybe 120 hz and see how that sounds. If you have adjustable high pass filters, switch those on for the front and rear speakers, and set it to whatever frequency you have the sub channel set to. The idea is to not have a "gap" in the frequency response between what the sub handles and what the other speakers handle. If the high pass setting is not adjustable, I wouldn't switch it on. Most likely it will cross over higher than you want, and you'll have a wierd hole in the audio range.

      Yes, the stock premium sound system has an amplifier hidden behind the spare tire area. You want to bypass that if its still there or you'll probably smoke it. If you aren't using any of the original speaker wires, then just unplug it and forget it exists.

      Dimmer ground? never heard of such a thing. Is this on the radio or on the car side of the harness? if its on the radio, consult the manual. If its on the car side, just leave it unhooked. It probably does nothing but its safer to not connect it than to find out it really should not go to ground.
      86 Lincoln Town Car (Galactica).
      5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

      91 Lincoln Mark VII LSC grandpa spec white and cranberry

      1984 Lincoln Continental TurboDiesel - rolls coal

      Originally posted by phayzer5
      I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

      Comment


        #4
        Oh! Did not know about the stock amp.
        I was going to use all the stock speakers wires however: I've got RCA cables running from the head unit to the amp, and then speaker wires running back to the dash, where I soldered the wires to a harness I bought and plugged that in. There's a grey one and a black one... I think grey was the 8 speaker wires, and black was the other controls (antenna, amp turn-on, power, ground, etc.).

        SO, since there was a stock amp... did I just plug my amped speaker lines, to go to ANOTHER amp? I don't think it'll be any louder: just a muddled signal.

        How do I bypass the amp?
        It occurs to me, that while rooting around under the dash, I did see what appeared to be a second grey harness full of speaker wires under the passenger side, to the right of the head unit. Is that a bypass that ford left for people upgrading their sound system...?

        I did not however solder back into place the original amp turn-on wire; that I bypassed and ran my own wire back to the new amp.

        Comment


          #5
          Originally posted by BerniniCaCO3 View Post
          Oh! Did not know about the stock amp.
          I was going to use all the stock speakers wires however: I've got RCA cables running from the head unit to the amp, and then speaker wires running back to the dash, where I soldered the wires to a harness I bought and plugged that in. There's a grey one and a black one... I think grey was the 8 speaker wires, and black was the other controls (antenna, amp turn-on, power, ground, etc.).

          SO, since there was a stock amp... did I just plug my amped speaker lines, to go to ANOTHER amp? I don't think it'll be any louder: just a muddled signal.

          How do I bypass the amp?
          It occurs to me, that while rooting around under the dash, I did see what appeared to be a second grey harness full of speaker wires under the passenger side, to the right of the head unit. Is that a bypass that ford left for people upgrading their sound system...?

          I did not however solder back into place the original amp turn-on wire; that I bypassed and ran my own wire back to the new amp.
          best and easiest way is to run all your own wires mang
          89 townie, mild exhuast up grades, soon to have loud ass stereo....

          Comment


            #6
            But I've already reassembled all the trim, it took so long to tear apart :-(

            Comment


              #7
              wait-- opened the spare tire compartment, easy enough, and the only thing I see is a rather small light grey box with cooling fins on it bolted against the rear of the compartment, closest to the tailgate. A set of wires clips in, another set of wires clips out again. Is that it? If so, I'll just cut it out and solder the wires directly together! That will be easier than running fresh wires to all of the speakers, especially since I've reassembled most of the trim after laying my own wires.

              But before I chop out something important, does that sound like the stock amp to you?

              Comment


                #8
                Thats the amp. They actually make a bypass kit for this, its got the proper connectors so you can just stick it in between the two factory harnesses. Or you can solder the wires together. Not 100% sure if they are a color for color match though. You'll want to consult the EVTM to verify this.
                86 Lincoln Town Car (Galactica).
                5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                91 Lincoln Mark VII LSC grandpa spec white and cranberry

                1984 Lincoln Continental TurboDiesel - rolls coal

                Originally posted by phayzer5
                I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                Comment


                  #9
                  cool! called best buy, and they don't have any in stock. Kinda like to get this done sooner than later, and some of those harnesses are mighty pricey for what they are ($12 for a pair of 2-wire speaker harnesses, e.g.).

                  I'll check the manual, then probably solder away!

                  Comment


                    #10
                    Originally posted by BerniniCaCO3 View Post
                    cool! called best buy, and they don't have any in stock. Kinda like to get this done sooner than later, and some of those harnesses are mighty pricey for what they are ($12 for a pair of 2-wire speaker harnesses, e.g.).

                    I'll check the manual, then probably solder away!
                    goto metras website they have what youll need for wireing harness
                    89 townie, mild exhuast up grades, soon to have loud ass stereo....

                    Comment

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