LS430 rear subwoofer replaced
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Just to clarify - people mistakenly refer to using lower impedance speakers (like using 4 ohm speakers on an amp rated for 8 ohm speakers) as overloading the amp - but technically that is not a correct description of what is going on at all so it ends up making a complex subject even more confusing.
So here is an attempt to clarify - Using speakers with lower than recommended impedance (lower ohm rating) can damage an amp or at least cause it to run very hot because the low impedance speakers present too low of a resistance load instead of too much of a load.
For the purposes of this explanation we will ignore the effect on overall impedance load of multiple speakers being wired to the amp. A simple way to explain this concept is if you just short out the plus and minus speaker out terminals on the amp using a length of copper wire the impedance goes to nearly 0 (no electrical resistance at all). So a 2 ohm speaker setup presents more resistance than a plain copper wire, a 4 ohm higher still, and 8 ohm is higher resistance again and so on. So higher ohm speakers actually put more "load" on the amp and that is what an amplifier out put circuit needs to "push" against to do its job. When the amp has no resistance to push (load) against it tends to over heat to the point of causing damage although many modern amps sense this situation and will cut out before damage occurs.
It gets a little more complex when using multiple speakers and multiple amp stages - what matters is the overall impedance that the amp stage (channel) sees across all speakers and crossovers that are wired to it. As an example two 4 ohm speakers wired in series produces an 8 ohm load, wired in parallel produces a 2 ohm load.
As impedance gets higher the load on the amp increases so wiring three 8 ohm speakers (like a woofer, midrange, and tweeter) in series would present a 24 ohm load to the amp - this is also not good and besides significantly reduced volume would also overload the amp.
So here is an attempt to clarify - Using speakers with lower than recommended impedance (lower ohm rating) can damage an amp or at least cause it to run very hot because the low impedance speakers present too low of a resistance load instead of too much of a load.
For the purposes of this explanation we will ignore the effect on overall impedance load of multiple speakers being wired to the amp. A simple way to explain this concept is if you just short out the plus and minus speaker out terminals on the amp using a length of copper wire the impedance goes to nearly 0 (no electrical resistance at all). So a 2 ohm speaker setup presents more resistance than a plain copper wire, a 4 ohm higher still, and 8 ohm is higher resistance again and so on. So higher ohm speakers actually put more "load" on the amp and that is what an amplifier out put circuit needs to "push" against to do its job. When the amp has no resistance to push (load) against it tends to over heat to the point of causing damage although many modern amps sense this situation and will cut out before damage occurs.
It gets a little more complex when using multiple speakers and multiple amp stages - what matters is the overall impedance that the amp stage (channel) sees across all speakers and crossovers that are wired to it. As an example two 4 ohm speakers wired in series produces an 8 ohm load, wired in parallel produces a 2 ohm load.
As impedance gets higher the load on the amp increases so wiring three 8 ohm speakers (like a woofer, midrange, and tweeter) in series would present a 24 ohm load to the amp - this is also not good and besides significantly reduced volume would also overload the amp.
Last edited by Jabberwock; 12-03-12 at 06:08 AM.
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hi am new to the forum, i want to replace my front door speakers and rear door speakers also the rear sub woofer this is what i bought what do you guess think any other suggestions
Kicker 10C108 Comp 10-Inch Subwoofer 8 DVC (Black) i bought 2 of these
Planet Audio AC2000.2 MOSFET Two-Channel Power Amplifier, 1000 Watts x 2 Max Power
Eminence Eminator 1506 6-1/2-Inch High Power Car Midrange 8 Ohm 4 of these
i have a 2003 g2 430
Kicker 10C108 Comp 10-Inch Subwoofer 8 DVC (Black) i bought 2 of these
Planet Audio AC2000.2 MOSFET Two-Channel Power Amplifier, 1000 Watts x 2 Max Power
Eminence Eminator 1506 6-1/2-Inch High Power Car Midrange 8 Ohm 4 of these
i have a 2003 g2 430
Last edited by foresure84; 12-09-12 at 08:59 AM.
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sorry i dont, im not an audio specialist, just needed to replace the rear sub but didnt want to pay $350 for replacement, i do need to replace the front speakers due to some rattle noice, another project to do...
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On my sub, which from what I have been reading is an issue, the foam was bad in a couple of spots causing a rattle. I used silicone on the outside edge to re seal it. That worked quite well, rattle gone and cost of repair around 4.00, just a thought.
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Refoam the rear speaker and you will only have the labor to remove and install the rear seat to deal with. I was able to find the front speakers new (OEM) for $99 each around 2 years ago.
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[QUOTE=HDMike;7650808]On my sub, which from what I have been reading is an issue, the foam was bad in a couple of spots causing a rattle. I used silicone on the outside edge to re seal it. That worked quite well, rattle gone and cost of repair around 4.00, just a thought.[/QUOI have the same issue my 2006 subs makes a small rattle noise..Exactly what typ of silicone did you use..Also did you just remove the cover and was able to repair it from there
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