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2002 pontiac trans am

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=102269
Printed Date: June 08, 2024 at 4:51 PM


Topic: 2002 pontiac trans am

Posted By: slowpoke96z28
Subject: 2002 pontiac trans am
Date Posted: February 17, 2008 at 12:21 AM

if the factory monsoon speaker at the B-pillar is a DVC with two 4ohm coils each with their own channel off the monsoon amp, what would happen if i used a higher quality aftermarket speaker with one 4 ohm voicecoil, and used both channels' positives to the speaker's positive and both channels' negatives to the speaker's negative. if i can only use one channel off the amp, i will, but i'd rather be able to use both because i figured the two channels wouldn't exceed the power rating of the speakers. if i wired it in this fashion, wouldn't each channel still see a 4 ohm load? so in essence it would provide the same power to the single voicecoil as it did to the compined power of the dual voicecoils on the factory, right? i'm trying to wrap my head around the physics of it, but i am just not sure if it makes sense to wore the single voicecoil speaker this way.




Replies:

Posted By: i am an idiot
Date Posted: February 17, 2008 at 4:42 AM




Posted By: slowpoke96z28
Date Posted: February 17, 2008 at 1:49 PM
wth is this bro? i dont have a classic car. its a 2002. i'm trying to answer a specific question and understand the physics behind that answer.




Posted By: i am an idiot
Date Posted: February 17, 2008 at 3:15 PM
The website I posted earlier has several different size Dual voice coil speakers.   I would not reccomend connecing the 2 positive wires together to feed the single coil of an aftermarket speaker.  I wasn't trying to hurt your feelings by calling your 6 year old car a classic.  I have no idea what size the speaker in your b pillar is, but I figured that this website may have a dual voice coil speaker that would fit.  No physics involved.




Posted By: slowpoke96z28
Date Posted: February 17, 2008 at 9:41 PM
can you explain why you wouldn't reccomend doing that? on that site, my car isnt even an option to choose, thats why i didnt know why u put it up there




Posted By: i am an idiot
Date Posted: February 17, 2008 at 10:22 PM

I know of only 1 automotive amplifier that is capable of doing what you are asking to do.  I really can't think of a way to explain why you can't do it. 





Posted By: slowpoke96z28
Date Posted: February 20, 2008 at 12:35 AM
can anybody explain the physics behind it? i'm imagining it wouldnt be much different than two batteries in parallel on a diesel starter. they take more current to turn the starter, so they use a second battery to provide more cranking amps.  one batery would be capable of 9500 watts, but two can put out 19000 watts. why wouldnt it be the same for having two voltage sources wired in parallel to one higher quality, higher rated voicecoil vs one source on one voicecoil and one on the other on a not as high quality dual voicecoils?




Posted By: slowpoke96z28
Date Posted: February 21, 2008 at 7:42 PM
anybody out there that can help me and i am an idiot out? or is there maybe a different section for these kinds of posts?




Posted By: sparkie
Date Posted: February 22, 2008 at 11:52 AM
You need to use a dual voice coil speaker. You can't run an amp like you described to a single voice coil speaker. What you would be doing is shorting out two audio channels and the amp won't take this.

-------------
sparky




Posted By: slowpoke96z28
Date Posted: February 22, 2008 at 7:07 PM
how is it shorted? wouldnt both channels see the same impedance? what am i missing?




Posted By: i am an idiot
Date Posted: February 23, 2008 at 8:24 AM

According to information I have gathered at the other forums that you too have been visiting.  The speakers in question are subwoofers.  I would have to assume that each speaker has a left and right channel voice coil.  Thus meaning that each speaker will get a left channel signal and a right channel signal.  You cannot connect these 2 seperate outputs together.  It is a bit more complex than 2 batteries in a diesel truck. People have tried changing the speakers and using only one set of the wires.  The results are all the same, less volume.  If the left coil of the left speaker is paralelled with the left coil of the right speaker, the amp is seeing a 2 ohm load on each channel.  And the same for the right coils.  If this is the case the amp will put out half of the power into a 4 ohm load vs. the original 2 ohm load.  I know Infinity is now making some speakers that are 2 ohm.  I do not know if they are making woofers alone.  In order to verify my theory, first you need to remove the panels so you can see the speakers.  Balance to the left and see if both speakers still play.  Balance to the right and make sure they are both playing.  If they are both playing all the time, you will need to get an ohm meter, remove both speakers, remove one voice coil from one speaker, balance the system and see which channel is still playing (left or right) Go to the other speaker and remove one coil from it.  You need to unplug the same channel that was unplugged from the other speaker.  Balance to left or right and make sure that both speakers play when balanced either left or right and do not play when balanced to the other channel.  Once you do  this, you need to turn radio off       This is  a very important step.  Turn the radio off. 

Using the ohm meter set to the lowest ohm scale, check from one negative wire to the negative wire on the other side of the car. We are hoping for a dead short.  0 to 2 ohms depending on the quality of your meter and leads of the meter.  Now do the same for the positive wire   check from one wire to the other wire on the other side of the car.  We are Hoping for a dead short here too.  If both the positive and negative wires are shorted, you can try to find a  2 ohm driver (single voice coil) and connect only one set of wires to it.  You need to connect the left wire to the left speaker and the right wire to the right speaker.

If something is not exactly as I am assuming you really need to let me know before you connect anything.





Posted By: slowpoke96z28
Date Posted: February 23, 2008 at 10:24 AM
i will do the balance test. IIRC, when i use the balance to either way, the other side goes totalling silent, but i will make sure to see. thanks bro.




Posted By: i am an idiot
Date Posted: February 23, 2008 at 7:46 PM
If it is as you remember, you need to use the meter and check from negative to negative on the 2 wires on the left speaker.  Then check the positives.  I really can't see them being the same wires.  If they were coming from the same place GM would probably have just ran 1 pair of wires and then just jumped from one coil to the other.  Let me know what you find out.




Posted By: slowpoke96z28
Date Posted: February 27, 2008 at 1:32 AM
i did NOT recall correctly. either way i turned the balance knob, i still got a little sound out of the other one. it almost seems as if only one voicecoil on either side is affected by the position of the balance knob and the other coil still played. i would really need a 4 channel o-scope to really see what was going on, but i only have a 2 channel. i guess i'll do one side and record the waveforms and the do the other and compare all 4.   I do believe that both voicecoils in each speaker are 4 ohm a piece, so each channel from the amp is seeing 4 ohms impedance(nominal, i guess) on 4 separate channels. no voicecoil is wired in parallel, according to the schematic at least.





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