Front speaker not working...Why?

[Guest]

I just recently got a new CD stereo installed in my '70 Skylark Custom and now the front in-dash speaker does not work. It worked fine with the old AM radio that was in there before I got the now one installed, but why not now? The front speaker was the only original speaker in the car, and the newer ones work fine. Does anyone know why it doesn't work anymore?

[Guest]

Who installed the CD you or a stereo installer? I just ask because I am one. Ok was the speaker working and then quit? Has it worked at all since the new install? What make of cd player? Any info you give me will help. If you can remove the cd player and unplug the unit you can do the old battery test on the speaker. I beleive the factory colours for the front spk should be either "grey and beige or "dark green and light green" I cant remember which on the old single spk cars. If you take a AA battery and touch it across the spk wires to the front spk and the spk makes "popping" noises it should be ok. You should also make sure it is not a grounded type spkr where one terminal gets chassis ground. If you get no popping noises and determine the spkr is pooched you may have to replace it. Depending on if you got the room or not you should be able to get a pair of 4inch spkrs in there with a little work. If you want to go that route it will also keep even loads on all 4 channels and prevent further problems. well I'm rambling now gimme more details and I'll try to help you figure out some things to do.<P>Lee

[Guest]

Cicuit City installed my stereo. Yes it was working fine with the AM, but now I can't hear anything. The CD player I got was the Pioneer DEH-P3100. Also, weren't all of the speakers in the older cars grounded type speakers, because I think this is, because that is how the original rear speaker was rigged until I replace it and that is how the whole car was set up because when they installed it they told me that they had to rewire the entire car because of this. Thank you for your help. Ramble all you want. I'm very intersted to know all that anyone says.

[Guest]

Sorry it took so long to reply. Busy weekend. Ok start with the basics. It may have been all fact spks were chassis grounded on one terminal. I'm not an exactly sure. As long as the rear spks have been rewired probably the best thing to do is replace the factory dash spkr with 2 4inch spks. Then they can be hooked up the the front left and right channels off the cd player. I'm not sure wether your fact dash spkr is 4x10 or 6x9. I'm guessing 4x10 because a freind of mine has a 71 chevelle and what I did was make a small wooden plate with the 2 4 inch spks side by side with each other that would fit in the factory opening under the dash pad.I also installed under the spks what we call a "spkr hat" or foam baffle. Rule of thumb with spks is to always have the front of the spkr sealed from the back of the spkr. To experience the difference take any speaker that is in a box , listen to it , then take it out of the box and listen. It will now sound like crap. Hence the reason for the spkr hat it will make them sound better. Sound will typically leak down thru the bottom of the dash and they wont sound as good as they could. The one problem if you want to use the fact single dash spkr is that it cause an unbalanced load in the amplifier. It starts to put stress on the amp and they typically dont last as long. My guess is they may not have even hooked up the fact dash spkr. Oh in some of the older cars they only ran 1 wire to each rear spkr and grounded the other terminal but then they would actually run 2 wires to the spkr in the dash because it was a short wire to run and not usually a good place to ground something. In older radios they use what is called a "common gound" system. This is typically done with low power radios. You can still find aftermarket radios like this at you local suplus or bargain store. They use chassis ground for the ground path of the spks. On most newer and high power radios they use a fully floating ground. This means that each spkr has its own ground and must not be connected to chassis ground or the smoke gets let out of the radio. To remove the dash pad usually involves removing screws from the top located in the air vents and on the under side where the pad overhangs the dash. Its usually a simple operation. And then from there its pretty self explainatory as to removing the fact spkr. The wiring colors on MOST new aftermarket stereos is as follows. Red= ignition 12v Yellow= constant 12v(memory pwr) Black= ground Blue=remote turn on(pwr ant trigger). White and white-black trace= left front spkr Grey and grey/blk trace= right front spkr Purple and purple/blk trace= right rear spkr Green and green/blk trace= left rear spkr. The black traces are negatives. It is important to get the positves and negatives hooked up correctly or the spks will work "out of phase" with each other. Demonstration of out phase take your home stereo spks hook one up backward and listen. You will notice you now have next to no bass. One spkr is now pushing out when the other one is pulling in thus cancelling each other out. To check if your spks are out of phase balance to the left, then balance to the right, if the bass gets stonger when you are on one side or the other then your spkrs are probably out of phase. If the sound gets louder when balance is centered they are in phase. Have you ever seen the guy driving down the road with his 6x9 spkrs sitting on the rear deck? I get a good laugh out of silly things like that. A trick thing you can do for the rear spks if you have the aftermarket grills mounted on top is this. My freind with the chevelle bought a new NOS parcel shelf cover. Basically a piece of painted cardboard. I then placed the cover on the rear deck and traced the 6x9 holes from underneath. I then took some graph paper and marked a grid in the oval traces. I then perforated the cover inside the trace lines according to the marked grid. There is an easy way and a hard way to perf the holes some install shops have a special perf tool for this purpose. I could not find any installer in town with one so I did it the hard way. Take a gasket punch of about 3/8 size and punched each hole individually. Two hours carefully punching holes so I would not mark up the panel. But success! and happiness on my buddies part. Another way you can do the rear deck is if you already have the coles cut in your cover is to take it out. Cover the cover with 1/4 foam. Get grill cloth (acoustically transparent fabric) and cover the whole thing. "VIOLA" (yes I know I spelled that wrong long time purposefull habit) you now have a stealthy install that sounds good and looks good. I hope my miscellaneous ramblings are of some asistance. Any other questions feel free to ask. The more I type the less coherent my thoughts get. Gotta go.

[Guest]

My god I had no idea I typed that much. Long winded or what?

[Guest]

Another thing I was told was that since they were 10 ohm speakers that they create to much of a load for the radio, and as a result you can't hear any sound coming out. Could this be the case?

[Guest]

Duh I forgot about that during my diarrhea of the keyboard.<BR>The higher the impedance the easier it is for the amp to drive the load but results in less volume.When we say there is a heavy load on an amp is when the impedance gets too low.Typically most decks can handle down to 4 ohms you try and hook up more spkrs than the available # of channels and life expectency will suffer. <BR>Thats why we start to add outboard amps that can drive multiple spkrs off of each channel. Low impedance loads will result in increased power output until the o/p transistors can no longer handle it. You can also think of it this way. A light bulb filament has a resistance across it. The lower the resistance the brighter the light. The higher the resistance the dimmer the light.

[Guest]

So then that's a yes?

[Guest]

Oops. Yes.

[Guest]

If this is the case then why couldn't any of the many so-called "installation speciallists" that I asked tell me that was the problem. I mean don't all of the older cars come with the 10 ohm speakers? They couldn't even tell me at circuit city where they installed the stereo. I don't understand why because they were even able to look at the speaker, and even the Circuit City Roadshop Manager couldn't tell me why. So what should I do? Should I replace it with two 4" or just put in one 4x6?

[Guest]

Is it a 4x6 speaker? If it is its smaller than I thought. I personally would put a pair of 4inch up there. (3 1/2 inch if the 4's wont fit are another option)and keep the original spkr if you ever want to put it back to stock. This is if you want to keep the car appearing stock. If stock appearance is not important spks in the doors would sound better(thats another ball game). Why nobody could tell you what it is I have no explanation. If the guys are 25 or younger chock it up to experience or lack therof. I've been doing it for 10 yrs and don't see alot of cars over 20 yrs old. In this business a lot of the install work is based on "figure it out as you go along".When trying to keep up with todays "electrotenocrap" ie. radios that if they are removed cause the check engine light to come on its hard to remember the old stuff. Hope this adds some insight.

[GSMAG]

Check out this link for speaker explanation.<P> <A HREF="http://home.netcom.com/~gnenad/speakers.html" TARGET=_blank>http://home.netcom.com/~gnenad/speakers.html</A>

[Guest]

gm indash speaker is almost always a 4x10<BR>or 4x8, a very long, odd looking speaker. <P>i am not an electronics whiz, but the the impedance info given above sounds correct. i tried in two different gm's to make that center speaker work and never succeeded. <P>in one case i modified the bracket to hold a single 4x6 and in the other, i used door speakers and left the factory center speaker alone.<P>allan

[Guest]

If you guys are using the factory radios and not aftermarket ones you can still do the pair of 4inch spks in the dash by wiring them in series instead of parallel. 2 automotive 4 ohm spkrs in series will give you 8 ohms 2 automotive 4 ohm spks in parallel will give you 2 ohms. 8 ohms is still a usable impedance that should not blow up an old radio. 2 ohms will blow up that old radio. The 2 4 inch spkr trick can be used as a stop gap measure until you get a replacement factory spkr so you dont get sick of the sound of you own voice.(unless you can sing of course). you can probably pick up a pair of cheap "bulk"(factory looking speakers) for $20-30 or a pair of really nice 4in spkks for $60-100 a pair.

[Guest]

I just went to <A HREF="http://home.netcom.com/~gnenad/speakers.html" TARGET=_blank>http://home.netcom.com/~gnenad/speakers.html</A> but the guy says there that the only way to hear music with the old radios is to have to old 10 ohm speakers and if you don't have working ones, then you should have them rebuilt with him. This is deffinately not right. All you really have to do is find an 8 ohm resistor for a 2 ohm speaker or 6 ohm resistor for a 4 ohm speaker and put them in series with the new speakers, because resistance add in series. So that takes care of the resistance problem.

[Guest]

With the 2ohm resistor thing, what wattage and tollerence would you get? Not to mention, where does it go. :/<P>TIA<P>SM ;-)<BR>