95Honda

I'm lucky, I never had any of those horror stories happen to me, I know they did though. The only drivers I had (ongoing) problems with were some Adire ones... A friend of mine still has one of the original (mid 90's) 12" underhung TC drivers going strong... He uses it daily...

Soldering is great, so is a good crimp. Both together is almost foolproof.... A bad crimp is just a huge problem waiting to happen. I can't tell you how many ends I have re-terminated because someone used a hammer, pliars or vice to smash the connector on all half-assed...

Just to reiterate. Also, if you can see definite frame rails under the car that go all the way from front to back, it isn't unibody. But, alot of cars these days are unibody. I bet a web search would tell you within a few minutes if you have a unibody car or not.

Efficiency ratings apply in every enclosure application. This rating tells you how much output a given driver will have with a certain input. Watt for watt, the BTL is the loudest sub FI makes because it is more efficient, in the right enclosure, of course.. Yes it would be kind of strange to buy a BTL and send it 100 watts, but it would still be loudest driver you have with your 100 watts.. Just because a driver has stiff suspention doesn not mean it needs alot of power. The suspention is just one of the components thta make up the driver charactoristics. For example, if you have 2 drivers and one has lower compliance (this is the definition of "stiffness") but the other has increased motor strength, the other driver may still have increased cone travel at the same power output.... Same case with a BTL, just because it's suspention is stiff, doesn't mean the cone won't move as much. In fact, it will more than often move MORE because of the increased motor strength... This is how it is more efficient, if the cone wasn't moving more, it wouldn't be ass efficient. But again, this is all on the box and frequency being played.... But hopefully this helps some understanding here... Yes, this has been covered before, alot. But it is good to see a few guys remembering/understanding this... Now there is also a flip side to this. With all other parameters being equal (same motor, cone mass, etc) when you decrease compliance (say add spiders) you do a few things. Generally speaking, you increase Fs, increase mechanical power handling and you decrease the Vas of the driver. Now, efficieny and Vas are directly proportional, so buy decreasing compliance, you decrease efficieny at the same time. But there is a lot of factors that play into this. For example, if you had a BTL 18 and only had 1 very compliant spider, it would be much more efficient than one with stiff suspention, but the downside is that since Vas may have gone up so much, you now would need a much larger box to get the same response, additionally the mechanically handling would be very poor. You may gain a few db or so within it'susable power handling range, but anything more than say 100 watts may send the coil into the backplate of the motor or bottom out the triple joint... Adiitionally the drastic change in mechanical Q may render the driver too peaky for music. So basically, the engineers at FI choose the best ratio of compliance to motor stregth (and yes alot of other paramters) until they got a driver that was efficient enough and had enough mechanical handling to be thier loudest sub. If there was a class that was say 100 watts and a single 18" driver ONLY, you may see a driver design like something I have been talking about here, but of course there is not, so there isn't really a driver designed like that. But hopefully this helps with the understanding of compliance, efficiency, etc....

I like the impact crimpers that you hit with a hammer, I bought my last one from PartsExpress about 7 years ago, I just looked but they don't carry them anymore, or I couldn't find them at least...

Sure, except I'm talking about stuff thats going in doors and kicks here....

If you have a full frame car and not unibody, running ground wires to the back is pointless... It would take tons of runs of 0 gauge to have lower resistance than a frame if you do your connections properly. If you have a unibody car then you may benefit from running a ground(s) to the back.

I have been using TC souns on and off for over 15 years. They make good drivers. Most people on here don't understand what you are paying for with this type (lms ultra) sub. It uses a very linear motor system with extremely linear cone travel. It is meant more for low distortion at extremely high bottom octave output. You are paying for a proprietary motor and suspention system. They also can get loud, but if that is your goal, there are much better choices... If you are looking for simply low distortion at high displacement, there probably aren't many better choices, especially sine the Brahma and Xbl2 XXX aren't made anymore... These also have (had) very linear motors. You could also look into the Exodus lines, they are now using Xbl2 motors also, but I haven't tried one of thier new subs yet so I can't comment.... But, was this what you were really after?

LOL, why? To have less vent cross sectional area and more vent velocity?

No you don't need an Eq. They will have a crossover point regaurdless if they are active. The only difference between active and passive is that with active, the filtering takes place before the final gain stage... For you this means you would't be designing and building passive crossovers, and from what I gather so far, you would not be wanting to do something like this anyway.

The point Jim was trying make with the Zaphaudio link is that there are a bunch of reviewed, tried and tested drivers out there that are all very easily attainable. All you have to do is look at the data on the drivers and make a decision. Also, don't worry about the difference of "home audio" vs "car audio" drivers.... There really is no difference other than the fact that many car audio drivers are around 4 ohm... But honestly, there is abbsolutely nothing wrong with running 8 ohm drivers in the car... Do your homework and make an informed decision. If you want to go active and buy the raw drivers from somewhere like Madisound or PartsExpress, you will be getting about double the quality at half the price of most any main stream component set.... And if space for tweeters isn't a concern and you can tolerate a 3-4" tweeter faceplate, you can get better tweeters for around $50 than what is in ANY car audio component set under a $1000.....

The bigger you go, the bigger peak the box will have and potentialy be louder.... If you go smaller, you'll loose efficiency and need more power to do the same thing...

I have had nothing but great experience with the SXs. They are probably some of the most tried and true subs out there, before the SX they were the HC for quite a while.... Really decent sub... All the others are nice also, really a matter of taste I think....

I still think you are missing what I am saying. If your deck has factory ground, then everything is NOT terminated to the same place. Herein often lies the problem...... You have no idea how that factory ground is set up. Seriously, I mean each peice of equipment connected at the same ground potential. This means a wire that goes from each component to one central ground location in the vehicle, your distro sounds like agood start. Every single system I have installed in the last 4-5 years gets a 8 awg run for the deck ground to the central point. I have had systems with 10+ pieces of gear in the signal chain with "0" engine noise issues, all the time, every time..... Even the cheapest, POS equipment (Pyramid, Legacy, Dual) will never have engine noise issues if you follow these basic guidlines.... I know because I have literally installed a ton of it over the years for cheap-asses....

There is a (decent gauge) wire from EVERY piece of gear in your car connecting the ground to only one spot in the car? I mean your head unit, signal processing, amps, everything... Is this the case?

The #1 cause of engine noise is a ground differential between equipment in your signal chain. What this means is, if there is a difference in voltage potential, it will try and equalize through the signal cabling. This will cause all of the AC present from the alternator (every single alt puts out some AC, all the time) to be passed where it can't be filtered since it is in the audible range (engine RPM). The only way to cure this to equalize the ground potential between equipment. The only reason noise filters/isolators work sometimes is because either they A, disrupt the path the DC ground potential path, or B filter every last bit of AC component from the DC. Both of these means are inferior because they limit system bandwidth and current delivery. Unless your equipment is broken, you will not have engine noise if everything is at a common ground potential AND excess EMI is not being induced on your low level signal cabling, as the latter is hardly ever the case, even with bad rectifiers in your alt and crappy spark plug wires.

Battery isolators are NOT what you want for the high current demands of car audio, no matter what the "expert" at the RV/auto parts store tells you... Additionally, you will never, and I mean never(!) hook up a 12V car battery in series with another for anything but a 24V vehicle. Period. By wiring in parellel, as everyone has advised, you are increasing the current delivery of the 12V electrical system in your vehicle. Your are also lowering the total ESR of your electrical system and increasing your instantaneous current delivery every time you add another battery in PARELLEL and decrease the DC resistance of you wiring. This is all a good thing. Just remember one thing, something has to recharge all those batteries, it is a balancing act, if you consume more current you must supply more current, and the only thing that supplies this current is your alternator....

Here is what full clipping sounds like. Use this function generator. Listen to a 60Hz sine wave (unclipped) and then listen to a 60Hz square wave (this is full clipping). This is a gross example, but you wanted to know what clipping can sound like.... http://www.marchandelec.com/fg.html

No, I was deleting this post because the function generator was changed, it used to have square wave, not anymore. Disregaurd the post.

On a budget I would reccomend the PartsExpress HF subs. They have lower distortion motors than just about anything out there until you double the price. They are a little over $100 a pop for the 12s.... Read about it near the bottom of this page... It measured almost as good as $700 Skaaning model... It probably has lower distortion in its xmax rating (14mm) than just about anything you'll see from most car audio companies.... http://www.zaphaudio.com/tidbits/ This is if you really care about sound quality as #1.....

To be honest, most reccomended sealed boxes (and a majority of all home audio mass-market sealed subwoofers) have a Q higher than .7. Alot of car audio alignments push Q near 1. There isn't anything wrong with this, besides the fact that you can get a small box, the ripple in response above Fc with a Q of .7+ is what most people prefer to hear. It also sounds louder most of the time. F3 doesn't change drastically with Q in sealed alignments like it does with ported. In fact, F3 isn't the primary goal when adjusting Q. The goal is a smooth response (or not smooth) and .7 is the where ripple must be less than +/- 3db and is kind of a standard. By manipulating Q you are really changing the sound by changing the overall response (high and low) not just the low-end cut-off. The biggest factor in getting a low Fc in sealed alignment is a driver with a low Fs..... And a medium to high total Qts. If you don't have these two things to start with, you'll never get a low Fc in a sealed alignment without Eq. Also, don't get hung up on Fc/F3 alone. Because a sealed alignment has a much shallower roll-off than a ported one, the F3 can be much higher than a ported F3 and still acheive similar low-end output.

I think everything models exactly how it should, you just have to be able to look a little deeper into the results... Don't pay so much attention to F3 in modeling programs if you shoot for a Qtc less than .7, this is because the F3 actually goes up, even though you have increased low end extension, it just has a shallower roll-off. The lowest F3 a modeling program will give is always near .7 for a total system Q. Be cautious in going a ton lower than .7 with sealed alignments. They get flatter and flatter in response, but to most of us, they start sounding a little lifeless... I have built tons of low Q subs for the home environment, Qs as low as .5.... I liked the results sometimes, many that heard them didn't so much.... One thing I never pay attention to is the recomended box alignements alot of programs give, alot of time they really aren't waht you are looking for and you can do much better by tweaking the volume (and tuning if vented) to get what you think is the target you are looking for, alot of times this is drastically different than what is suggested by the program. Just keep your eye on parameters such as group delay, xmax and vent velocities... It's funny, I hear all the time how subwoofers like the BTL doesn't model at all, I have plugged in the T/S parameters several times (the ones on Bladeice) and with Bassbox Pro, I end up with pretty much exactly what is reccomended by FI.... You just have to interpret the results the best you can... If I were you, assuming what you have said so far, I would shoot for a Q at little lower than .7, and then make it smaller as suggested which has been really good advice BTW... Also, don't forget that the total Q of the system will never been anywhere near as low as the driver Qts. So if you have say a high Q driver (like some of the LMS subs) you will never get a low Q system alignment. This isn't a bad thing, it just may mean that you need some additional Eq for the bottom end and LP filter set right to get rid of the ripple above Fc.

I bet those will get plenty loud.... You have plenty of power also... I think you'll be happy...

See that knife like edge on the internal port mouth? Round that off, that is exactly what you don't want to do. Where will the port external port opening be? Are you just goint to router out the front baffle?

They'll work with just about any 2-way crossover you get, they just won't work well. Every single different component set should have a crossover optimized for its particuar drivers. There is no such thing as a "universal" passive crossover, you'll see them advertised sometimes that way, but it is marketing. Do you still have the old ones? If you get me a close up picture of the guts from a few angles I can give you a schematic and help you buy PC boards and all the parts to build yourself a new set, a set that would probably sound much better... Would probably cost you around $40