95Honda

You know, I keep adding all this up in my head, but seriously, do most people also know how much all this will weigh??? LOL...

That is just stupid... Do you realize that even with 50 watts they will be louder than any other of the FI subs?

I'm in Kaiserslautern, thought I would see how far away you are... Seriously, The SPL is mostly in the execution, I don't put all the stock in the particular drivers or the amount of power. The box in my Avatar used 8 RE 8s. These aren't SPL subs. They are actually quite inneficient, but they still put up 143db on the Termlab with 150 watts of total power. This was verified by Black00 (Marshal Joyner) They did this because I literally spend days on the computer modeling different alignments until I came up with one that had the perfect response curve to achieve the target SPL I was looking for at the frequency I wanted. If you think about it, 143 db isn't much lower than what people are doing with 10X that much power.... It really is all in the execution...

This paragraph makes me realize how much time I wasted in this thread..... Nick- I will never get your comments on the box modeling problem of BTLs. Every time I run the parameters of the old BTLs (as posted on Blade Ice) and the new ones, I always model a ported box similar to the ones reccomended on your site. No speaker program I know of will put a driver with a Q as low as the BTL in a sealed box without severe low end roll-off and the possible need for Eq... Every single driver can be described by its electromechanical charactoristics, I don't think the BTL is an exception. This was the last time I will ever comment on running the T/S parameters of a BTL on this site. -Mike

Where are you in Germany?

The BTLs are nothing like any of the Audiopulse drivers. They are both engineered twards different goals. Since the T/S parameters are now listed on the FI site for the BTLs, you can compare box size, efficiency and response of all the drivers you have been mentioning by simply downloading/purchasing a modeling program. You'll find that you answer many of your own questions that way, and gain experience in the process.

An easy way to figure it out is subract 3db for a 2.83V rating every time you halve impedance from 8 ohms... So, if it is a 4 ohm sub, subtract 3db, a 2 ohm sub 6db, etc.... This is just a rough way to get the numbers, but it is usually pretty close. An example is- Sub X is rated at 90db 2.83V/1M. It has dual 4 ohm coils and the sensitivity is rated with the coils in parrellel (2 ohms). This sub is roughly 84db 1W/1M.

In that case, make a huge box and tune it around 40Hz....

Louder in a similar alignment, not neccesarily the exact same box.....

You could look into a folded horn, something like a LAB horn. Using a single 12 or 15" driver. When you go folded, you can gain alot of enclosure volume efficiency. The horn that Dan Wiggins was using with the Tempest was a scaled up LAB (or Cerwin Vega variant), and was around 7-8 cubic feet externally (IIRC) and was pretty efficient and could be adapted to a car. I think it got down into the upper/middle 30's OK. The plans may still be on the net for it...

The W7 was JL's statement woofer. There probably isn't another made by anyone with as much one-off custom parts, this is reflected in the price. It is a seriously well built, low distortion driver. It isn't overpriced, considering the fact that nobody other than a chinese build house full of shoeless children could build it cheaper... The Q is also a great woofer, but I wouldn't expect leaps and bounds (especially in output) over a W7.

It is pretty dumb to build a box smaller to increase mechanical handling. It won't yield any more SPL if both alignments are correct, and just lowers efficiency and increases distortion....

Clippind doesn't burn tinsel leads. It never has, and never will. The signal is arbitrary. The leads burn from too much current flowing through them. Thats it. Period. When they start to heat up, they start to do something similar to what is refered to as "Thermal Runaway" (you'll hear this alot with semiconductors). Basically, this is what happens- #1 They begin to heat up from too much current #2 The heat increases the resistance of the tinsel #3 As resistance goes up, more voltage is dropped across the lead and the more power (heat) it dissipates #4 The hotter it gets, the more resistance it has... #5 And so on, and so on, and so on..... Until it melts.... Again, THIS HAS ABSOLUTELY NOTHING TO DO WITH CLIPPING or O-SCOPES....

If an amplifier is amplifying, the output signal is always larger than the input, hence "amplification". If it does not put out more voltage it is usually a buffer to isolate and drive varying impedances. Amplifiers are rated with voltage gain, i.e. X volts in gives you Y volts out depending on the gain of the amplifer. The gain adjustment (if there is one) is what sets the ratio of input voltage to output voltage (gain). If there is no gain adjustment, it is fixed as set by the manufacturer. This amount of gain is rated in db. 25-30db is an average gain for an amplifier. Each 6 db doubles the voltage output as compared to the input. So if you have an amp with 30 db of voltage gain, 1 V on the input equals 32V on the output.... If you apply an input voltage that exceeds the threshold of what it takes to produce maximum amplifier output (voltage) then you run the amp into clipping. The input voltage to do this is all dependant on the voltage gain of the amplifier. It cann't be broken down (correctly) any simpler than this.... Again, if you apply more voltage to the amplifier input than what is required for full output, it clips.

No and No. Clipping is when the AC component of any amplifier/buffer in signal chain is trying to swing more voltage than what the DC rails supply. Basically, the top and bottom of the sine, or any signal, get flattened, or "clipped" An O-scope never prevents clipping. The only thing that prevents clipping is not overdriving the input to any of the stages of amplifier/buffer in your signal chain. If you have a tough time with this, a simple answer is the volume knob on your deck caauses clipping when you turn it up too high....

Actually, you know what is even more stupid that I see day to day is people judging subwoofers off of You-Tube... That has got to be one of the dumbest, idiotic things I have ever heard of.... Entertaining, yes..... Informative? Only to a monkey.....

The BTLs will be louder for Rap than any other Fi sub with the same power.... So if you want the loudest, that is what they are.... Additionally, you can never "underpower" them or any sub for that matter... And I'm not sure if you mean you can run up to 9ft3, becuase if you can, the pair of 12s will more than likely be a little louder than the 1 15" sub..... Maybe not a whole lot louder though...

I'm not sure you understood everything you were writting about, especially the T/S parameters...

Come on you guys, seriously.... Why do you post stuff like this????? There is no such thing as too little power. Again- THERE IS NO SUCH THING AS TOO LITTLE POWER You probably didn't hear the noise anymore because, I don't know, you were wanging' the crap out of the sub?????

If you use the Tang bands sealed, you might not feel they have enough low end. They both are low Q drivers designed for ported alignments. But, they also both have very small Vas, so small boxes are still very possible. Here is a box I built for my dad, each Tang band Neo 8" gets .3ft3 and each pair is tuned to 33Hz with a 3" I.D. port... They absolutley hammer like this... You may get away sealed just find depending on cabin gain of your vehicle.... You need to download WINISD, Boxplot 2.0 or something similar and run the numbers yourself, that is the only way you will learn about this stuff...

Higher tuning with more area if possible. The box in my Avatar has 6 4" Aeros for less woofer displacement (8re8s) than you have. It also does 143db on the T/L with 150watts and over 150db with a tad over 1000. I used to keep 4 of them plugged for normal music (30Hz tune), 2 plugged for rap (40Hz tune) and none plugged (50Hz tune) for burps.... This was in a 78' Bronco.

Best bang for the buck comes from Tang-band. Either thier Neo 8 or standard motor 8. They run well under $100 a pop on Parts Express. the standard motor 8s are on sale often for around $50. I would be willing to bet they would beat 1/2 the 8s already reccomended on this thread on everything but looks... One thing though, determaining power handling needed without modeling the driver in a chosen alignmnet is both meaningless and, well, just dumb. This type of logic is why BS power ratings are silk-screened on dustcaps... And this is coming from someone who has installed more than 50 RE8s, a ton of Rockford, Kicker, and so many other 8s I can't even count in my head....

Another quick analogy I like to use to help people understand Mms is like this- You take driver A) with a Mms of 100gr and driver B) (an identical driver) with a Mms of 100gr. Now, put these two together face-to-face isobarik and you have a combined Mms of 200gr (+ whatever the air weighs in between them) Now, you have doubled Mms, so transients should suffer.... When in fact they don't.... They don't because you now have twice the motor force for twice the Mms. Everything equals out, even though you have more Mms. This goes to show you can still have Mms that is larger if you counter it with motor force, all while saving "transient response"... Because honestly, isobarik alignments are know for alot of things, but degraded transient performance over that of a single driver isn't one of them.... But really, this isn't transient response so much as efficiency in relation to Mms.... No matter how heavy a cone is it will still move back and forth as fast as the AC signal, it will just move less given more mass with identical motor force... I think Le has a lot to do with transient performance and Mms has a lot to do with efficiency, within reasonable limits, of course... I also think heavy cones with lots of inductance render a driver with poor efficiency and poor transient behavior... Even if it has 5" of xmax...

You asked a meaningless question, so did I.... Nobody can tell you if you need "BP" or not... The power handling of your sytem is determained by your enclosure alignment, not by the thermal power handling of the woofer. If you are thermally limited, you designed a poor alignment that really isn't too efficient and is not appropriate for your driver.... Additionally, there is no such thing as underpowering. 900 watts is alot for any driver.

I can't reccomend much other than the Dayton RS stuff for the price... I have used tons of them, my father is still using a pair of 6" RS 4ohm mids in an active setup. He has been going on with them over 2 years now... They sound great, in fact, I chose them at the time for the promising off-axis performance I had read about... I think the phase plug they have helps a little in that department...