SPL??

Thank you again.

I have a FI BtL with the ufo motor that I need to recone. I see more then one BtL recone kit and I'm not sure what one is the correct one I need. What one do I need. Also, my woofer was 1ohm DVC but its been so long since I ordered it that I'm not sure if ai ordered the universal BTL or not, how can I check if its a univerasl BtL motor?

No, but I watched youtube videos and learned how. Its going to be real simple for be cause I won't have to clean off the basket, I'll be starting with a new basket.

Thank you.

This is true.

As a general rule, a lower FS almost always indicates that a woofer that would be better at low frequency reproduction than a woofer with a higher FS.. This is not always the case though, because other parameters affect the ultimate performance as well....

Large xmax is also an important factor cause it wil allow the woofer to move more air. This is the reason that SPL woofers normally have larger xmax then SQ woofers.

Before cabin gain 90db@1w= 90db 90db@2w= 93db 90db@4w= 96db 90db@8w= 99db 90db@16w= 102db 90db@32w=105db 90db@64w= 108db 90db@128w= 111db 90db@256w= 114 90db@500w= 117 90db@1000w= 120 90db@2000w= 123 90db@4000w= 126 Each time you double your power you will gain approx 3db. And each time you double the amount of subwoofers you will gain approx 3db. And FS gives you a great idea of how the sub will preform low FS= deep punchy subwoofers and higher freq= louder and less punchy.

Nice system!

Yes it was insured and UPS has agreed that the box was "mishandled" on their part and are sending me a check.

System 1: For me 12" FI BTL UFO DVC 1 OHM wired to .5 OHM Old School MMATS DHCx2200.05 amp = 2200wrms @.5 OHM & 13.8v or 2300wrms with 14.4v Box tuned to 34hz This system isn't currently installed.. it was in the trunk of my Jaguar for many years and it sounded good and got loud (Not competition loud) I never had it metered so I'm not sure what the SPL was probably 140ish.. I'm going to be installing it in my Ford Explorer pretty soon. System 2: For my wife MA 3600wrms amp thats overrated due to the fact that they rated it at 17volts. The amp is approx 3000wrms at 14.4 volts. Not the greatest amp...But I got a good deal, I picked this up for $150 used off craigslist. One kicker L5 15" in a sealed box that I have had for many years and never used it... This system isn't currently hooked up, but my plan is to either buy one more L5 15" and have two of them. Or, sell the L5 15" and get a sick sub like a Mayhem 18" and give the 12" BTL to my wife.

Third place is supposed to be the BTL N2 not the N3.. TYPO.. lol*-Between the BTL N2, ZCON & MAYHEM..Based on the FS I would think these subs all sound about the same, they would all sound good.. they all are about the same efficiency (High Efficiency) so the important number here is the rms power. The Mayhem takes first place, The ZCON takes second place, and the BTL N2 takes 3rd place. I believe these subwoofers are currently the best woofers on the market, if I failed to mention any worthy subwoofers please list the specs.-*

Here is some more information.. I sold my BTL on eBay and UPS destroyed it during shipping, now I'm in the process of rebuilding it... I think I'm going to keep it now. I may possibly turn it into an 18". Check my photo gallery for pics!

I gave your post a +^ I love everything you said excluding the very ignorant part. lol I agree with you there is many factors; you can get a lot of cabin gain from resonant frequency and the box freq can get you a lot louder or deeper.I look at all of the specs of a subwoofer not just the ones I listed, the specs I listed are the ones I feel are the most important! I think the rest of the specs are much to advanced for most people who use and enjoy car audio, I didn't realize this forum was filled with advanced car audio people.

Sorry to dismiss your post, I'm sure you re a car audio guru. I just was going for louder subwoofers that still have good sq but I didn't make that clear in my topic. Can you please tell me how make a build log?

Ok, I'll add a build log :-) But please be open to my topic, I thought it was a good topic.

I opened this topic to compare the specs of the worlds best "SQL" woofers and see what woofer is the best in the "SQL" category. honestly there is no best ""SQL"" since that is a very loose term .... also, the "best" is usually whatever fits your budget, goals, your install and restrictions..... sooooooo give us that info first I'm not here to buy car audio, I already own high end car audio.

I opened this topic to compare the specs of the worlds best "SQL" woofers and see what woofer is the best in the "SQL" category. And to see if there are any subwoofers that are as good or better then the ones I listed that I'm not aware of. Also, I figured it would be a good read for people.

This topic is/was 100% serious. If you don't agree with what I'm saying please explain why. Please use these specs when explaining why you dissagree. Fs = resonance frequency of the driver. In free-air, the driver's impedance will peak at this frequency. Pe = Thermal capacity of the driver, in Watts. If continuously driven above its rated Pe, the driver may prematurely burn out and fail. Qes = Electrical Q of the driver at Fs. Qes is a measure of the driver's tendency to resonate at Fs, based on its electrical characteristics, e.g. magnet strength, magnetic circuit characteristics, etc.). The driver's overall resonance characteristics are usually dominated by Qes. Qms = Mechanical Q of the driver at Fs. Qms is a measure of the driver's tendency to resonate at Fs, based on its mechanical characteristics, e.g. surround compliance, the compliance of the spider, weight of the cone, etc. Qts = Total Q of the driver at Fs. Qts is a measure of the driver's tendency to resonate at Fs, based on its overall characteristics. Qts can be calculated using the equation: Qts= Qms*Qes/(Qms+Qes)) Re = DC resistance of the driver's voice coil. Re is less than the driver's rated impedance (normally 4 or 8 ohms). Sd = Effective surface area of the driver. Roughly equal to the area of the cone plus 1/3rd of the surround. Xmag = [DUMAX] Excursion limit due to the magnetic limitations of the driver's motor. Xmag is defined as the displacement at which the BL product has fallen to 70% of its value at the cone's rest position. Xmech = Maximum physical excursion capability of the driver. Exceeding Xmech normally results in damage to the driver. Xsus = [DUMAX] Excursion limit due to the driver's suspension. Xsus is defined as the point at which the compliance of the suspension has decreased to 25% of the value at the cone's rest position. Xmax = Linear (one-way) travel of the cone. Xmax is used to determine the maximum linear SPL capability of the driver, and can be defined in a number of ways. The DUMAX definition is objectively the best one, and it is defined as the shorter of the Xmag and Xsus values, in each direction of cone travel. This definition is more useful than the older definition of Xmax, which was solely dependent on the length of the voice-coil vs. the length of the gap. Vas = Equivalent air compliance. The volume of air that has the same compliance ("springiness") as the driver's suspension. Because less air is more "springy" than more air, a large Vas represents a "loose" suspension Vd = Peak displacement volume. Vd = Sd*Xmax

SP4 SQ sub FS 24.7 This thing goes low. Deep bass! Spl: 87.8dB 1W/1m 3000w RMS this woofer has lots of power but its not efficient so it wouldn't get nearly as loud as the other woofers listed above so.. I didn't list it as a part of the list. I would compare it to a evil, xxx and other subs like that.