Effect of tweeters on ohm impedance?


2007-09-26 1:29 pm
Hey all....I have been wondering about this for a while....My tweeters are 4ohm, and my 6 1/2's are 4ohm...They are running on the same wire (tweeter wires are spliced into the wire) to my amp for my highs. Now, the rears are just 4ohm. Because my tweeters are 4ohms, and so are my 6 1/2's, even though they aren't exactly wired in parallel, does this mean I'm getting a 2ohm load to my amp? I didn't plan it that way and they aren't exactly wired parallel but they are running off the same wire so I guess the tweeters effect it enough to get a 2ohm load?

Just something I need to know if I try to look at a component upgrade in the future. Wouldn't want to get something that has 2ohms and then have my amp shut down cause it's below a 2ohm load....
If your drivers have an XO on them, the impedance will still be 4 ohms. Impedance is frequency dependent so if each of the drivers is only covering part of the spectrum, the impedance reflects that.

EDIT: If you are running the woofers straight and the tweeters with only a cap, the same thing applies as the rising impedance of the woofer puts it high enough so as not to affect the overall impedance when you add the tweeter with it's cap.
The impedance of a piezo tweeter is dependent on the frequency of the input signal. They are essentially capacitors that produce sound.

If you use them, you need to insert a current limiting resistor in series with them. If you use a resistor that has a value equal to or greater than the lowest rated impedance of the amp, you can parallel as many as you'd like. The resistor will prevent the load from dropping too low.

Even if you use only one, you should use the current limiting resistor. Some amplifiers don't react well to driving a purely capacitive load.