bkolfo4

If you are favoring the Q, also look at the AA Havoc. AA is the dealer based company owned by Scott - same guy that owns Fi. http://www.ascendantaudio.com/havoc.php

The SSD. Nothing wrong with 500 watts. Even if you had 800 watts, it would be less than a 2 dB difference in output.

Like I have said before, it normally works as a gross estimate, but you suspect someone is creating a design with the wrong port area, the correct questions to ask would be: what driver are you using? How much power? Tuning frequency? But all I ever see now is "that is only 8 sqin per cuft, you need at least 12". Sorry, I should have read and resisted typing. . . :-)

Different boxes will sound different in the same car, but port area should be sized based on the port operating without compression and noise which has nothing to do with the size of the box. Sorry. . .just drives me nuts that a couple of manufacturers gave gross estimates on port area based on the drivers they sell so everyone is not calling them asking "how much port area do I need", and somehow it becomes a law that everyone quotes. And I bet over half the people quoting it have no idea how a port should actually be sized. . .

Why do people continue to worry about how much port area there is per cubic foot???? They are NOT related!

For 4 ft apart, you do not need so many runs, unless you are going to have to connect all the amps in one location. Just get 4/0 and be done. Easier than multiple runs of 1/0.

The problem is no one knows the exact answer. If you know what you are doing, your amp settings are correct, and your box design is correct, 3000+ watts should not be a problem for a loaded BTL.

Why respond? Please explain why adding more xmax and more copper does not increase power handling. . .and why you need experience for the cooling option to help.

Adding long coil adds additional power handling. So does adding heli cool option. . .

That calculator is known to make mistakes when calculating L-shape ports. . .

Passive radiator looks similar to a subwoofer without a motor. The cone is weighted to adjust the "tuning" frequency. Works like a port, but you can get really low tunings without long ports to worry about. Looks great Steve - If you ever build another set, get those drivers butted up against each other. At least the tweeters. You will get a much better frequency response. . . Brian edit - here is some interesting reading from a man that is known in the home audio world as an expert in line arrays. If you have time, read the section on driver separation, page 11. I have tested this when I built the line arrays I post pics of here in the home audio section. You can hear a big difference in tweeter response as you move the drivers closer/farther apart. http://www.systemsolutions.co.za/Tech%20Zone/Line%20Array%20White%20Paper.pdf Brian

Dayton from parts express are very nice and priced right!

Your DMM is reading DC resistance. That is the resistance that would be seen if you applied DC current (like a 9 volt battery or hooked it up to a car battery). Music is an AC signal. Because the subwoofer VC is a coil, it acts like an inductor. The resistance of a coil with an AC signal applied actually varies with frequency. The impedance of the voice coil is rated base on an average resistance taken over the subs operating frequency range (there are more conditions than just the average - do a google search for nominal speaker impedance and you can read more if you like). Impedance rise is nothing more than the impedance changing at certain frequencies due to the box changing the characteristics of the cone movement. It may still be the same at some frequencies, but much greater at others due to factors such as the box tuning frequency. Bottom line - if your DMM says 1.4 ohms per coil, you have a dual 2 ohm sub. Series the coils on each sub, parallel the 3 subs. You then have a 1.333 ohm load, or .67 per amp. No problem for those amps.

Man Sundownz, we posted the same thing. . .does not matter how many times it gets posted, people just don't understand the 1.4 ohms DCR vs. 2 ohms nominal AC impedance. . .

If the DCR is 1.7, they are not 1.4 coils. . . .

Are they 1.4 ohm, or is that the DC resistance??? Get dual 2's, series the coils on each sub (4 ohms), parallel the three subs for 1.33 ohms. Each amp sees 0.67 ohms. No problem for those amps.

What voice coils configuration do you have. D1 or D2? That info would help for amp recommendations.

Thumbs up for Mechman! Looks great Steve!

Edit: I should have read the build thread and your sig. . .(2) 18's. . .Nice

What is "underpowered"? Had a guy call me not long ago and ask about an AA chaos. Once I said they were rated 800 watts, he was nit interested because he only had 600 and did not want to blow it. I tried to explain a few things to him, but when I started talking about the woofer getting less than 800 watts at lower volumes even if it was on a 800 watt amp, he stopped me. He let me know he had been on the phone with crutchfield and I was the one confused. "A 600 watt amp puts out 600 watts all the time, it is the voltage that is changing." At that point, I told him about the 600 watt AA Arsenal. Back on topic - I would personally go with one 18 over two 12", but if you have room for one 18, why not go for two 15s?

What condition are your batteries in? What wiring are you using? Assuming the alternator is setup correctly, the batteries or wiring could be holding it down. Is the voltmeter placed on the alt output post, or the battery post? I would start with a known good DMM and measure output at the alt. Thumbs up for Mechman. Great prices and great customer service!

That's no joke. . .

I would figure out the volume of that enclosure, get the t/s parameters of the mids, and model it up in a free program. Build a graph of output and excursion vs. frequency for the sealed enclosure and use it as a baseline against several potted enclosures. Start with a HP filter of 80 Hz and look at port tuning of 80, 85, 90, etc. Then move to an 85 Hz HP filter and look at port tuning of 85, 90, 95, etc. You might can pick up a nice gain in the midbass while reducing the driver excursion. Nothing wrong with reducing excursion on a driver playing midrange. . .

Another thumbs up for Matt and Mechman!

AQ2200D. $389 shipped.