BKOLFO4

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Yes it will. . .

692

All I can say is there must be something weird going on with that amp between the two modes. Ohms law is a physical law that cannot be broken. . .I understand the voltage/current is changing with the amp in the two modes, but the voltage and current across the subwoofers voice coils is staying the same in the two different modes. For the same power, it does not change. . .If it does, you are providing more power to the coils. You say it yourself - Subwoofers are dumb, they do what you tell them. When you wire 2 coils in series, each coil sees the full current from the amp, and 1/2 the voltage. In parallel, each coil sees the full voltage from the amp, and half the current. So when the amp changes from 2X voltage to 2X current, it does not matter to the sub. . .Physical law that works in real life just as it does in theory. Cannot be broken. I think in the case of the JBL, there is more going on than just a change from high voltage to high current. You know I like to debate with you Nick - Hope you are not getting upset with me

PM me your zip code. Brian

That is why I quit running US Amps in my vehicle. . . I got major magic smoke and the amp killed the sub it was connected to more than once. Two of those times my entire family was in the car (wife does not like loud music at all, so the radio was turned way down). Riding along and hear a "pop", look back and one sub would be sucked in as far as it could be. Smoke coming out of the box, smoke coming out of the amp. . .Wife and kids mad because of the smell even after the smoke cleared.

His example is not valid for what I am saying. I agree it would be nice to have higher impedance coils with higher voltage amps and less current. A dual 2 ohm sub getting 1000 watts per coil is going to have less current through it than a dual 1 ohm sub getting 1000 watts per coil. I agree with that 100%. But in the example we are looking at, we are comparing the same dual 1 ohm sub wired at 2 ohms or 0.5 ohms. At 1500 watts of input, it does not matter if the sub is wired with coils in series or parallel. If each coil is getting 750 watts, each coil has 27.4 amps of current going through it and 27.4 volts across it. No exception. If there is, then someone needs to reinvestigate V=i*R and P=V*i. To achieve less current through the coils, you need higher impedance coils, not wiring in series vs. parallel (it is great for the amp, but does not matter to the sub). In motor controller setups using my example, you are running all of your 1500 watts through 1 coil at a time, so higher power with low impedance coils could be a problem, because you are no longer dividing the current through 2 branches of a circuit, but feeding all of it through one coil at a time. I talked to Scott a long time about this and was the one who told him Kicker was shorting the unused coil while the other coil was being driven. It was driving me crazy trying to figure out how the heck they were driving one coil at a time and not changing the t/s parameters of the sub. Shorting the unused coil keeps the t/s parameters close to the original intent. But that is not why they do it. It keeps back EMF from screwing with the amp. The Warhorse prototypes started without shorting a coil and had many problems. The engineers finally figured out they were having problems due to the unused coil pushing back EMF back into the amp (at least that is what they told me) causing problems. To recap - Yes higher impedance coils with a given amount of power is a good thing to cut down on the current flow, but for a given dual voice coil sub, the coils will have the same amount of voltage across them and the same amount of current flowing through them for a given amout of power, regardless of if the coils are wired in series or parallel. Voltage divides across loads in series, current divides between loads in parallel. Maybe the failures you have seen come from what the amp is actually doing on its outputs when trying to run at low impedances. . .If the amp can't handle it, then all bets are off on how it should work. I have been beating the crap out of my 40.1's at 0.5 ohms for 2 years now. One amp per sub. Never hurt an amp or sub. . . Brian

0.5 is hard on the amps, but it should not matter to the subs. . .I am curious if you can give me the logic to why it hurts the subs. If I have dual 1 ohm coils, and I power the sub with 1500 watts @ 2 or 0.5 ohms, the current/voltage from the amp changes, but the voltage and current across each sub coil remains the same. The coils are still 1 ohm, and it is still 750 watts per coil, so voltage and current across each coil is still the same. I think the problem with running at 0.5 ohms is still the user and their control of the volume knob. . . Brian

You just answered your own question. Excess glue or not, you are getting it hot. That smell is always my warning to back it down a little. . . Brian

Either one will work in 5 ft^3. If it was me, I would run the pair of 15's on something like an AQ2200D. http://www.audioque.com/aq/AQamps2200D.htm Brian

Did you get a tracking number? It will say when they ship. . .

It would be nice if they gave port dimensions. Who knows what it is tuned to. . . Using the dimensions they gave, the gross volume is 4.8 cuft, so that is already a red flag when it says 2.5 cuft per sub and cannot be more than 2.4 GROSS volume. Subtract driver and port displacement, who knows what you have. . There are some really nice premade sealed boxes out there, but I stay away from premade ported boxes. It may sound ok, but you may also end up with a damaged sub from high tuning frequencies. Brian

This is for EACH sub: The sub has 2 voice coils (two positive and two negative connections). Run a piece of wire from the positive of coil 1 to the negative of coil 2. Then wire the negative on coil 1 from the sub to the amp and the positive on coil 2 from the sub to the amp Wire one sub to each channel of the amp. This will give you a 2 ohm per channel load on the amp. Brian

Do a google search. . . Average person can hear a change of 1 dB. 3 dB is the mathematical gain from double power, but you rarely see it in the real world. If you add 2 equivalent sources in phase, mathematically you gain 6 dB. If they are not in phase, it will be 3-6 dB. Hard to predict in the real world, since you will not know the phase difference. . . 10 dB is double loudness to the average human ear. If you are running a dual 2 ohm sub, your actual impedance will be higher than 1 ohm, so you will more than likely not see 3000 watts. . .But if you do, they BTL will take it no problem

Yes they are. . .

I only cut with a router

If u r just looking for a kit, it normally takes 4-5 days for them to ship out when I have ordered them.

And from what I hear from a couple of people I have sold subs to, AQ has awesome customer service!

I would shoot for 4-4.5 cuft tuned to 32 Hz. Brian

What enclosure are the JL subs installed in???

I ran MT's. Nice subs, but they willnot handle power like the Mayhems. I have run (4) 15" mayhems in 11.7 cuft tuned to 35 Hz and they sounded awesome. Did 157.2 dB @ 37 Hz on 16,000 watts.

Havoc is a SQ sub on steriods. Best of both worlds. I heard Level 4's for the first time at a local comp. Nothing wrong with them, but I think the Havoc has features I would rather have - the biggest one is the integrated tinsel leads if you are going to be pushing them to the excursion limits. According to the specs, the Havoc has more excursion (almost the max you can get from the 12 spoke basket), higher power handling, higher Bl, and higher sensitivity. I also love the look of the Havoc dust cap Like I said, nothing wrong with the DC, but it looks to me like the Havoc has the edge. . .

I have used them. . . Great driver. Tough daily beater and great SPL. Sound great in the correct enclosure. I would still be using mine if it were not for the SMD sub coming. . . Brian

The amp will work with either. The dual 4 will maximize the output of the amp, but if you think you might ever decide to add a second sub, get the single 4 ohm and then 2 of them in parallel will give you a 2 ohm load.

What makes you think the Nightshade is an improvement over the BTL? Just curious. . .