Quentin Jarrell

You'll be good to go. Just make sure you have plenty of bracing. When making a long box you can run into problems with the front and back of the box wanting to flex when playing.

And I use these for deadlift. The heel is about 1/2 inch lower than the toes with barely any sole to speak of to help keep your toes up. However I lift sumo. http://www.prowriststraps.com/inc/sdetail/250478

I use these. The stiff sole helps keep your feet planted. And the heel height is ideal for most lifters. http://www.roguefitness.com/rogue-weightlifting-shoes.php

No what Fi is recommending is a reflex enclosure. What you are asking about is a single reflex bandpass enclosure.

I've got a couple from 2004. It's the CD they used to program the X5 Steve built.

4th order has nothing to do with the type of box. 4th order is the roll off of the box just like a 4th order butterworth filter. Any type of box, sealed, ported, sealed bandpass, ported bandpass, Infinant Baffle, ect, ect, ect. Is possible to achieve "4th order" if designed to do so

Op was banned a while ago.

Yea. Everyone really hyped up to hear it play. Not much people in my country have these amplifiers. And if I'm correct in saying, the very few who do (like 5 in total) are SQ guys. I may be the first here to be using this amp for a street beater system. Plan is to make it loud, but focus on quality. Want my music to sound 'rich' (no pun intended) and clean. Nice crisp highs, vocals I can listen to for hours, midbass to match and well, bass not only to shake the road itself when I'm ready, but to blend in with everything when I'm just driving around. Hey thanks. I could really get a set of these. Will order a pack and try it later on. Got to focus on saving for other equipment first. As for the VDRV light. Still need to understand what that means... I'd assume its the drive gate for the mosfets

Good bacon doesn't need to be refrigerated. I still have about 15 pounds hanging in the salt house from October.

that car feels more like a caddy to me

The below formulas I use in mathcad to do calculations. You can do them by hand to calculate power in a given box. [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

I wonder how the situation in NK is gonna affect amp production this year.

Check this site out. http://www.vibrationmounts.com/Products.htm

In 2006 I bought a brand new 350 dually. The same week I made a trip to flat tops Colorado and had 2 injectors go out ruining the engine. You can ask any mechanic and they will tell you Fords have more issues than any other manufacturer. It's got nothing to do with hating its just fact. I have a buddy that had a nasty dually. Don't remember who did the work but it had a twin turbo setup with something like 900 horses and 2,000 ft lbs of torque. It was a dodge but had some type of Cat motor put in it.

Hey thanks never even seen that. I will have to how to make this work or something different. What do u suggestThere are tabs on the back of the seat that slide into the rear wall of the cab. Something akind to a ironing board hanging over the top of a door. For safety reasons I wouldn't go any higher than the stock floor bolt will allow. ~1 inch. I have easily done over 200 boxes under the back seats of trucks. Depending on the year under the bottom of the seat will be hollow. Therefore a downfired box can have a hump by the speaker magnet to allow for a deeper sub. You have a lot of options. Your budget will determine which route to go. Personally if it was my vehicle I would do a single Jl W6 12 or SSA ICON 12 downfired. The enclosure would go all the way across the back seat with the sub on the driver side and the port on the passenger side with the port exiting towards the passenger door. However my build skills are fairly above average.

Or you could use all thread and hang em off the rear deck.

Told u

No that's the price of owning a FORD

You know upholstery suppliers make steering wheel kits with the sewing holes pre punched.

What year is this? 2" ain't gonna work. The tabs on the back of the seat won't have anything to hold on to.

What's the going rate for a 966

The M3 is a dog compared to the 911. Not even a comparison.

Well the viper is more my preference. I was trying to be non biased.looked at those too, but i think the Porsche fits me better. awd, turbo, small and handles like its on rails.. With a driver that actually knows how to drive the gen three viper tear the the 966 a new one on the track. Although the GT3 will give the viper a workout if its not the ACR model. But that is what the car was designed for. For the track. They are two completely different driving experiences. If I was going to be driving through town in traffic going to work I would want the 911. If I was cruising on the weekend with a little track time now and then I'd take the viper hands down. Hopefully ill be back in a viper by Xmas this year.

Well the viper is more my preference. I was trying to be non biased.

It's a 400 horse AWD car with traction control. Throw a set of PS2's on it and there will be no problems hooking up. They run good on the track. Fairly comfortable for daily driving but have a small cockpit.