Wow you don't know when to quit do you? Here's Scott's description and I quote:
" In extreme cases, too much resistance can be harmful but we're talking about nominal 4 ohms vs. 1 ohm. The impedance of any speaker varies with frequency. That's why it's called impedance and not resistance."
That is definitely not correct. Impedance is the AC equivalent of DC's resistance. It means to IMPEDE current flow, only it's called impedance because in an AC circuit there's something called REACTANCE. In Dc circuits it's simply RESISTANCE because it resists current flow and there is no reactance. It's the same thing in the simplest sense. AC and DC circuits have different analogy to describe the same basic functions. Impedance as well as resistance ALWAYS varies with frequency if you understand the very basic concepts of AC circuits. That's a given. But to say that the impedance of a speaker varies with frequency because it's impedance and not resistance is wrong, and that is NOT why it's called impedance. It's called impedance because it's affecting the AC sine wave of the audio. But I fail to see why any of this would matter to the OP. And now I will definitely end this conversation. You can carry on disputing me or trying to convince yourself that you and Scott are right, that's fine but I won't go to the trouble of explaining how wrong you both are. I have the feeling that you both might be the same person. Now if are you going to once again say that wasn't a "rational, non-personal discussion that actually backs up your erroneous claims against Scott " then I'd have to say you're just trying to create a problem. Have a good one. I'm done with this convo!
You're arguing semantics, and you're grasping at straws here. In an earlier post - which I don't feel like digging up and quoting - you said 'the impedance varies because the cone moves'. That is akin to saying 'the car travels down the road because people are inside'. While both things are in fact happening, they are not directly correlated. Your understanding of speaker impedance is clearly limited to what you've read on google. In fact, in another earlier post you alluded that everything in electronics is 'theory and not law'. Go ask your friend Google about Ohms Law.
You keep stating that the amp will be damaged if you connect a 4 ohm rated sub in place of a 2 ohm rated sub. What you're failing to understand is that the 2 ohm sub sees swings of 20+ ohms. If you measured the IMPEDANCE (and NOT with a multimeter, as that will just tell you the DC resistance of the voice coil at rest) you would see that. If you looked up the impedance plot like I suggested earlier, you would also see that.
Further, the amp doesn't really care at all about the impedance of the speaker. It cares about the current draw. The amp puts out a constant voltage for a given input signal. The WATTAGE - this is different than voltage - is determined by the impedance of the load. The lower the impedance, the greater the current draw. The amplifier is limited by how much current it can sustain.
I didn't come here to swing my dick or get in an argument about audio on a car forum. The point of my original comment was to try to help the OP with his subwoofer dilemma. I've spent the last 15 years designing and commissioning large format audio systems for stadiums, arenas, nightclubs, auditoriums, and performing arts centers. I've also mixed many Bands You've Heard Of[emoji769] on live shows, as well as provided sound reinforcement for several political figures such as Mitt Romney, Michelle Obama, Bill Clinton, and a few others.
I really couldn't care less if you believe me or agree with me. If you want to have a constructive discussion about audio, I'm happy to continue. If you want to continue to argue about impedance vs. resistance, I'm out.
