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You can easily blow that (and any car audio sub made) sub with a 2 kw amplifier if you try hard enough. Nobody can tell you what is safe. Additionally, there are no gain settings you can accomplish that will keep you safe under all conditions. You need to use your head, and your other senses, to tell when the driver is getting too much power...

Looking evil sir!

With a strapped pair of amps, each amplifier effectively "sees" half of the load. If you wire the subs in series-series for a final 4ohm load, then your final load is 4ohm. No changing that. Now, since the amplifiers are strapped each amplifier will "see" half of the 4ohm load. So each amplifier will effectively be operating at 2ohm, and will output power accordingly. If the amplifiers are 1500w @ 1ohm each, then they are probably around 750w @ 2ohm. So you would have a total of 1500w of power since each amplifier would be operating at 2ohm and outputting 750w, which is a combined 1500w. From above, each amp would effectively "see" .5ohm but the actual load is 1ohm. If you had two 1500w @ 1ohm amplifier strapped into a 2ohm load then yes, the total power would be 3kw.

Sick!

contact singer alternators and you will never have a problem

That's a huge box for such a small woofer

Dirty Clean, ready for assembly All done

Everything is out on the hood, great left and right channel separation. And you can really hear the depth and staging at any volume! Mid bass like a mother! The ISO 10's dig deep!

They can be found towards the end of this [Last modified 07-Feb-07] SPEAKER DESIGN EQUATIONS 3.6 Bill McFadden 1993 [[email protected]] The most current version of this file can be found at: http://www.rdrop.com/users/billmc 1. Introduction This is a library of equations for designing ported and closed-box speaker enclosures. The equations were taken from speaker design books and technical papers by Richard Small and Neville Thiele (see references in tutorial section). They are designed for un-stuffed enclosures. Refer to the references for more information on stuffing. The equations are intended to be used with the HP48GX/SX multiple equation solver but can also be run with the solver built into the HP48SX. The binaries are provided in uu-encoded and ->ASC form. An RPL version is also provided, but does not include the binary variable Mpar needed by the multiple equation solver. The initial default speaker parameters are for the Eminence 18029 18" driver. I welcome any comments or refinements. 2. Variables The main directory is called SPKR and consists of two subdirectories: CB Closed Box Design PORTED Ported Box Design Running the multiple equation solver from either subdirectory will produce a menu of variables: Vas Volume of air having same acoustic compliance as driver suspension Qts Total driver Q at Fs Fs Resonant frequency of driver PEmax Thermally-limited maximum RMS input power SPL Efficiency of driver in dB SPL at 1W/1m Dia Diameter of driver xmax Peak displacement limit of driver diaphragm (1/2 of "throw") Vb Inside volume of enclosure Fb Resonance frequency of enclosure F3dB Half-power (-3 dB) frequency of loudspeaker system response Fmax Upper frequency limit of driver's piston range dBpeak Maximum peak or dip of loudspeaker system response Par Estimated displacement-limited acoustic power rating Per Estimated displacement-limited electrical power rating \Gno Driver efficiency (\Gn is Greek character eta) PeakSPL Thermally-limited RMS sound pressure level in passband Sd Estimated effective projected surface area of driver diaphragm Vd Peak displacement volume of driver diaphragm K1 Power rating constant K2 SPL rating constant The following additional variables are defined for the closed box case: Qb Total Q of system at Fb Amax Maximum amplitude of loudspeaker frequency response Vr Ratio of Vas to Vb Qr Ratio of Qb to Qts and Fb to Fs The following additional variables are defined for the ported box case: Dmin Minimum diameter of tubular vent to prevent excessive vent noise Dv Diameter of tubular vent Lv Length of tubular vent For the ported box case, the following apply: 1. Fb is the tuning frequency for the vent. 2. To use a square vent, enter the vent width times 1.13 or [2/SQRT(pi)] for Dv. 3. Design When designing a loudspeaker, two approaches may be followed. The easiest is to select a driver and design an enclosure for it. The other is to design the enclosure first, then select or build a driver that matches it. The choice between a closed box and ported box depends on several factors. Closed-box systems are the easiest to design and build and have the advantages of smaller box size, good low-frequency power handling, and superior transient response. Ported-box systems are more difficult to design because they require precise duct tuning. However, ported boxes have the advantages of superior bass response, good efficiency, and superior peak power handling in the passband. 3.1 Closed-Box Systems Closed-box systems are designed around one variable, box volume. Box volume is a function of the driver parameters and the system Q, Qb. To design a system with minimum peak or droop in the passband, Qb must be 0.707. The designer has the choice of setting Qb and solving for the box volume, or setting the box volume and solving for Qb. There is also the choice of assigning values to both of these variables and solving for one of the driver parameters. To design a closed-box system, enter the CB subdirectory and run the multiple equation solver. Alternatively, run the built-in HP48SX solver and select DESIGN.EQ as the current equation. Choose one of the following variables to solve for and assign values to the rest: Vas, Qts, Fs, SPL, Dia, xmax, Qb, and Vb. If you don't have all of the parameters available, purge the ones you don't know, so they'll be undefined and the solver won't attempt to use them. At a minimum, you will need to supply all but one of Vas, Qts, Fs, Qb, and Vb. Next, press <- ALL in the multiple equation solver to solve for all the unknowns. If using the built-in HP48SX solver, you will need to solve for each unknown individually, using NXEQ to sequence through the equations. 3.2 Ported-Box Systems Ported-box systems are a little more difficult than closed box systems because there is an additional variable, tuning frequency. The optimum tuning frequency depends on the driver parameters and box volume. To design a ported-box system, enter the PORTED subdirectory. Run the equation solver of your choice as described above and enter the driver parameters. Notice there is no Qb variable. At this point solving for the unknowns will automatically create a system with optimum passband response. Alternatively, you can specify values for Vb and/or Fb to see what effect they have on the system response. To find the minimum recommended diameter of a tubular vent for the enclosure, solve for Dmin. This is smallest diameter permissible to keep the air velocity below 5% of the speed of sound. Higher velocities can produce audible noise. To calculate the vent dimensions, enter either of Dv and Lv and solve for the other, keeping in mind the minimum recommended value of Dv. 3.3 Cabinet Design In the CST menu of the CB and PORTED subdirectories is a key labeled BCALC. Pressing this key runs the box calculator program. Don't run it directly from the SPKR subdirectory, or it will not work properly. The program is rather crude, and does not handle dual woofers, but is adequate for most designs. It works as illustrated by modeling the driver as a segment of a solid cone: _____ /| ^ / | | / | | / | | _____ / | | ^ | | | | | | | Rdia | | Dia | | | | __v__ | | | \ | | | \ | | | \ | | | \ | | | \| __v__ | | | |<-Depth->| | | To use, enter the driver's depth (distance from front of driver to back of magnet) and press DEPTH. Enter the rear (magnet) diameter of the driver and press RDIA. If you want the program to account for any extra volume taken up by bracing and other drivers, enter this volume and press XVOL. The program uses the driver's diameter as entered previously in the equation solver. The dimensions default to English units. The program will only accept real numbers as input; unit objects will cause an error. (I said it was crude.) To change units, store a value containing the new unit by typing 'name' STO, where name is one of Depth, Rdia, or Xvol. The units of the results should make sense based on the units of the data, but I won't guarantee it. You can also change the ratio of Height:Width:Depth used in the box calculation by pressing GOLD, 1.25:1, or CUST. GOLD selects the golden mean, 1.62:1:0.62 ((sqrt(5)+1)/2), which is the most common ratio. 1.25:1 selects another common ratio, 1.25:1:0.8. If you wish to use a custom ratio, enter it and press CUST. Each time you change a parameter using a menu key, the results will be recalculated and redisplayed. The display shows, from top to bottom, the driver's front diameter, the driver's rear diameter, the driver's depth, the extra volume taken up by other objects inside the cabinet, the total internal volume of the cabinet (including driver and extra volume), the ratio used to calculate the box dimensions, and the inside height, width, and depth of the cabinet. FIX 2 is the best display format to use with the default units. 3.4 Equalization of Closed-Box Systems There is a subdirectory in CB called EQUALIZER that will find the component values for an active equalizer that can extend F3dB of any closed box system to any desired lower limit (at the expense of efficiency and power handling--watch out!) See [11] for theory and circuit details. First, use the equation solver in the CB subdirectory to solve for the system as shown above. Next, enter the EQUALIZER subdirectory. Store the new desired cutoff frequency into F3dB, and press CIRCUIT. The component values will appear in the display. The values of R, C, N are chosen by the user to make the remaining component values realistic (see [11]). 4. Analysis 4.1 Frequency Response The equation solver generates three values related to frequency response, F3dB, Fmax, and dBpeak. F3dB is the frequency at which the acoustic output power of the speaker drops by half. Below this frequency, the response will drop 12 dB per octave for the closed box and 24 dB per octave for the ported box. Fmax is the upper limit of the driver's piston range. Piston range is defined as the range of frequencies for which the wavelength of sound is greater than the circumference of the driver's diaphragm. In this range, the driver's output is non-directional. Since this package models the driver as a piston, it is important to note that the equations are only accurate up to Fmax. In addition, because it is difficult to predict the driver's high-frequency behavior, it is a good idea to cross over to a smaller driver at or below Fmax. dBpeak is the magnitude of the frequency response peak or dip. For an optimal design, this value will be zero. To examine the frequency response in detail, enter the CB or PORTED subdirectory and run the plotter or built-in HP48SX solver. Select FREQresp from the equations catalog. F is the frequency variable, and dBmag is the response at that frequency. Using the solver you can solve for one in terms of the other. 4.2 Power Handling The equation solver generates power ratings called Par and Per. Par is the displacement-limited acoustic power rating. For the closed box, Par is the worst-case value for wide-band signals (all the way down to DC). For the ported box, it is an estimate based on the characteristics of musical signals. Per is the displacement-limited electrical RMS power rating based on Par. Because displacement-limited power handling is actually a function of frequency, the values of Par and Per only give small part of the picture. To examine power handling in detail, enter the CB or PORTED subdirectory and run the plotter or built-in HP48SX solver. Select POWresp from the equations catalog. F is the frequency variable, and Pmax is the maximum electrical input power at that frequency. Pmax is plotted first, followed by PEmax, the manufacturer's thermal RMS power rating. At some frequencies, Pmax will exceed PEmax. As frequency increases, Pmax can reach thousands of watts. Exceeding PEmax is permissible for short durations, but under no circumstances should you exceed Pmax even briefly or the driver may be physically damaged. Because Pmax is calculated with sine waves in mind, the peak power rating at a given frequency will be 2*Pmax. Using the ISECT function of the plotter, it is possible to determine the frequency range(s) over which it is safe to apply the full rated thermal power, PEmax, without damage from excessive displacement. Just place the cursor near the intersection of the curves and press ISECT in the FCN sub-menu. In the same manner, you can also use ISECT to find frequencies where the curves approach one another but don't touch. 4.3 Sound Pressure Level The equation solver generates a value for maximum SPL called PeakSPL. This is the maximum RMS output level of the system in the passband when driven by the thermally-limited maximum input power, PEmax. Like power handling, displacement-limited SPL is a function of frequency. To examine displacement-limited SPL in detail, enter the CB or PORTED subdirectory and run the plotter or built-in HP48SX solver. Select SPLresp from the equations catalog. F is the frequency variable and SPLmax is the displacement-limited SPL at that frequency. SPLmax is plotted first, followed by the thermally-limited RMS sound pressure level. As before, for frequencies where SPLmax exceeds the thermally-limited SPL, the maximum SPL may be limited to a value in between, depending on the peak-to-average power ratio of the input signal. Again, ISECT can be used to find the frequency or frequencies at which the displacement- and thermally-limited SPL ratings are equal. 4.4 Analysis of Equalized Closed-Box System Using an equalizer to extend the bass response of a closed-box system does not come without costs. For each octave of bass extension, a 12 dB boost is necessary (and requires 16 times as much power). To evaluate these costs, two equations are provided in the EQUALIZER subdirectory: FREQresp and POWresp. These function like their counterparts in the CB and PORTED subdirectories, but take into account the effects of the equalizer. Because I took the equations right out of the article [11] without any optimization for speed, these equations run very slowly. However, I left out the units wherever possible so the equations would run faster. FREQresp calculates the response of the equalizer, rather than the system, to give you an idea of the amount of boost required to equalize the system. The greatest boost occurs at the new F3dB. POWresp calculates the equivalent power handling of the system. At each frequency, Pmax is reduced by the amount of boost the equalizer provides. This is useful to see what the power handling of an equivalent, un-equalized system would be. There is no equation for maximum SPL vs. frequency because it is the same as the un-equalized system. 5. Design Equations Here are the equations used by the speaker design library. All values have SI (mks) units. ^ denotes exponentiation. LOG() is base 10. 5.1 Constants pi = 3.14159265359 c = speed of sound in air (345 m/s) Ro = density of air (1.18 kg/m^3) 5.2 Closed-Box Systems Vb = Vas/Vr Fb = Qr*Fs F3dB = Qr*Fs*((1/Qb^2-2+((1/Qb^2-2)^2+4)^0.5)/2)^0.5 Fmax = c/(pi*0.83*Dia) dBpeak = 20*LOG(Amax) Par = K1/Amax^2 Per = Par/(\Gno) \Gno = 10^((SPL-112)/10) PeakSPL = SPL+10*LOG(PEmax) Sd = pi*(Dia*0.83)^2/4 Vd = Sd*xmax Amax = Qb^2/(Qb^2-0.25)^0.5 for Qb >(1/2)^0.5, 1 otherwise K1 = (4*pi^3*Ro/c)*Fb^4*Vd^2 K2 = 112+10*LOG(K1) Vr = Qr^2-1 Qr = (1/Qts)/(1/Qb-0.1) Frequency-dependent equations: Fr = (F/Fb)^2 dBmag = 10*LOG(Fr^2/((Fr-1)^2+Fr/Qb^2)) Pmax = K1*((Fr-1)^2+(Fr/Qb^2))/(\Gno) SPLmax = K2+40*LOG(F/Fb) Thermally-limited RMS SPL = PeakSPL+dBmag 5.3 Ported Box Systems Vb = 20*Qts^3.3*Vas Fb = (Vas/Vb)^0.31*Fs F3dB = (Vas/Vb)^0.44*Fs Fmax = c/(pi*0.83*Dia) dBpeak = 20*LOG(Qts*(Vas/Vb)^0.3/0.4) Par = 3*F3dB^4*Vd^2 Per = Par/(\Gno) \Gno = 10^((SPL-112)/10) PeakSPL = SPL+10*LOG(PEmax) Dmin = (Fb*Vd)^0.5 Lv = 2362*Dv^2/(Fb^2*Vb)-0.73*Dv Sd = pi*(Dia*0.83)^2/4 Vd = Sd*xmax K1 = (4*pi^3*Ro/c)*Fs^4*Vd^2 K2 = 112+10*LOG(K1) Frequency-dependent equations: Fn2 = (F/Fs)^2 Fn4 = Fn2^2 A = (Fb/Fs)^2 B = A/Qts+Fb/(7*Fs) C = 1+A+(Vas/Vb)+Fb/(7*Fs*Qts) D = 1/Qts+Fb/(7*Fs) E = (97/49)*A dBmag = 10*LOG(Fn4^2/((Fn4-C*Fn2+A)^2+Fn2*(D*Fn2-B)^2)) Pmax = (K1/\Gno)*((Fn4-C*Fn2+A)^2+Fn2*(D*Fn2-B)^2)/(Fn4-E*Fn2+A^2) SPLmax = K2+10*LOG(Fn4^2/(Fn4-E*Fn2+A^2)) Thermally-limited RMS SPL = PeakSPL+dBmag

if it was a btl im not sure if i woulda said something or not;)

I am saddened this is the first people are hearing of b2 here....

I would wire it to the speaker inputs on your amp.

Nope those are 2 Lanzar 12's in the fold down box lmao. I still don't understand this guy, one day hes on chat saying hes 15(Cant even drive yet)? Now hes here saying school tuition is too high?

i didn't know nobody cares about "this kinda shit" or rap, its not in the rules funny though every demo vid has rap playing...... i wanted to share a funny video in the video section,so i did if u don't like it then don't reply, gtfo flaming members do i flame your factory painted lincoln? i lurk this forum frequently and rarely see any new content so excuse me 4 trying There's a problem with factory paint?

Is it a bootleg wheels on the bus CD?

x2

LOL....and walk away.

your so slow,. but ok .. if you wanna take the "serious" path now that you look like a child. then i dont really eat that much. infact my skinny little g/f eats more then me and MUCH MUCH faster.... but as where you only drink 1 drink with your huge meal.. i drink alot with my normal size slow meal... im fat . have been all my life, but im also 6'3 9 inch hands and a size 16 shoe. so im BIG AND FAT. and even if i were not fat i would still be bigjon jerk off. and to rest you theroys im not diabetic and i have an active job ( i move around alot.)

Tru's homework for today is to look up the definition of a)metabolism and b)genetics and for bonus points might wanna read up on how NOT to be a douche in a community of some pretty awesome people. Maybe start with "conversation starters for dummies" and maybe that will prevent you from inserting foot in mouth when trying to make conversation with someone who does not look exactly like you do

oh and now your stocking my youtube stream right? your so weak son.. get a life.

come on down to austin texas and well talk about it

Swat that gnat off your shoulder bro and keep keeping on! Its so far beneath you cant nobody see it! lol Edit- I HAD to upvote that pic tho lol

try unplugging your laptop from the wall, taking out the battery, and holding the power button for 20-30 seconds then put your battery back in. Then try booting into safe mode w/ networking and update your graphic drivers as shizz said.

If it was a CPU Cooling problem the laptop wouldn't blue screen it would just shutdown. The error its throwing is a GPU error due to corrupt Nvidia drivers, as shizzzzon said. Reformatting would probably do the trick but, that's assuming Rick has a copy of windows.

Not to mention assuming the laptop only has 1 partition he would lose everything on the laptop.

Catalyst Control Center is a program associated with ATI/AMD GPU's and has NOTHING Todo with Nvidia GPUs, nor will it tell you if something is wrong with your graphics hardware.

try unplugging your laptop from the wall, taking out the battery, and holding the power button for 20-30 seconds then put your battery back in. Then try booting into safe mode w/ networking and update your graphic drivers as shizz said. my ideas are better than your idea roflll unplug and blah hahaha and display control or whatever its called on nvidia, excuse me why don't u submit some more brilliant advice instead of trashing mine i waited a couple days before posting, i just wanna help ive fixed laptops with blue screen errors by reinstalling windows before so im sharing and shizzon no disrespect taken i understand this is a technical subject idk how it works im just putting what has worked for me if windows registry has multiple errors then it could "overwork" the cpu to the point of protecting itself to the blue screen? Removing all power from the laptop resets Cmos, so if for any reason something in the Bios was changed, it would be reset to default.

Shizzzon is steering you in the right direction, because if it IS a hardware related issue, reformatting wont do Jack.

please tell me more random person who knows nothing about me and johns internet fued

a memeber has sausage fingers and cannot type correctly

yea i got banned for making a support obama gun control thread when one of the admin is a real hill billy gun nut they have alot of gun threads and maybe you're onto something the car audio forum tough guys are all old and way past any kind of beginner stuff so far past that they have no patience at all and by old i mean over 25 this sucks for us who are in the middle of nowhere and have barely any car audio help because these guys who are on forum all day have attitudes usually personally i cannot believe they allow the skar bashing here when it is sold in ssa store

there is plenty of pointless skar bashing on here so much that i think they're trash yet do not know why they use cheap chinese labor.... ok so does sundown bottomline by bashing skar the way u guys do u are taking the profit that ssa would make from people buying in the store all thats offtopic HERE IS THE REAL SHIT bigjohn i am sorry to have made u stomp your feet and get your fingers all bunched when you type but from your demeaner on here i assumed you could take some playful shit talking pms and maybe talk some car audio too i have pm'd almost every regular on here at least once i guess my approach with u was a bad idea as you are emo

grats on having the loudest most expensive trunk setup

troll?

Thanks guys definitely eases the mind. I'll be sure to check under the hood from time to time though.

There are plenty of reasons for an amp not to be 1ohm stable. have you noticed how bad efficiency drops as you go down in ohm load? That's just one reason of many....

Just use whatever your electrical system can handle...