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New member Username: AlvingoPost Number: 1 Registered: Aug-05 | Hi! Im new here and I was wondering if anyone can give me some tips on how to built a box. I want deep bass and loud and i have a subwoofer 2 12 inches db312d crossfire that is 200rms, 350w maximum and dynamic power of 600w, and the db312d can provide a good punch in my previous setup in my car and now im looking forward to try deep and loud. I really appreciate if someone can help me. The amplifier is solid audio 1800rms @ 1ohms (a little overrated). The box that I made previously for this is vented as shown in its specs sheet.This is the parameters for this sub I dnt know, if it can handle for deep and loud application. Driver description 12" Subwoofer, Dual Voice Coil Mounting depth, in/mm 5.75/146 Woofer Outer Diameter, in/mm 12.5/318 Woofer Displacement, ft3/ltr .07/1.98 Impedance 4 ohm per coil Nominal power handling (RMS) 200 watts Maximum power handling (PE) 350 watts Voice coil -- size 2", 4 layer Resonance frequency (fs) 20.703Hz Qts .366 Qes .397 VAS, ft./liter 4.74/134.394 X-max, in./mm .312/8 Efficiency (2.83V/1M) 86.6dB The original box being given by crossfire is large vented volume: 2.9/82.11 tune to 29Hz Port 4" x 10.5" 25Hz 350 watts This box is more on Punch bass when i tried it! Hoping for replies! :-) |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9470 Registered: Dec-03 | I'd probably go for about 2cu ft per sub after port and driver displacement (net vol) and use a slot vent tuned to around 28Hz. that'd hit very deeply and pretty hard with that power. |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9471 Registered: Dec-03 | if that's not what you're after, you may want to look at different subs |
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New member Username: AlvingoPost Number: 2 Registered: Aug-05 | thanks for the reply :-) well, il try to make that! what if i used port would it make any difference? i already had a box 2.22 cuft and the port is 10.75. i can add the port length using elbow if its ok.um.. should i put fiber fill ? or not? |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9484 Registered: Dec-03 | won't need fiber fill, and shouldn't need to bend a 4" ID port for a 12" sub. at 2.2cu ft and 28Hz you should be around 10" in length I think. if you shoot for 34Hz you'd be closer to 7" and that's easy to get a straight port at 4" diameter. |
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New member Username: AlvingoPost Number: 3 Registered: Aug-05 | well when i computed winisd it says that the port would be around 16.81 inches. i dnt know if this is true or not. um... what software do yo used when computing boxes ? :-) |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9518 Registered: Dec-03 | a pencil and some paper www.bcae1.com has some java scripted calculators for port lengths. so does www.the12volt.com they'll help confirm any of your calculations. I may have been off. I was guessing at the lengths from memory, but I've rarely needed to bend a port, and when you do, you have a whole new slew of calculations to do to accomdate port velocity changes and tube lengths @ the turn. its a bit of a pain really. |
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New member Username: AlvingoPost Number: 4 Registered: Aug-05 | Yeah its really a pain! bending the port tube! i really dnt know how i can calculate when bending the port and maintaing the frequency! do you have any tips for that? :-)it will change the velocity and i dnt know if it sounds weird cz i never tried it. |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9536 Registered: Dec-03 | it's just a matter of calculating for the bend.. and if you're using PVC, you just use an elbow joint. http://www.amazon.com/exec/obidos/ASIN/0071448470 or http://www.amazon.com/exec/obidos/ASIN/0070580839 or http://www.amazon.com/exec/obidos/ASIN/1882580338 any of these books will help you with those calculations. for 34Hz with 2cu ft though, you're only at 11.7" with a 2ft^3 box so you don't need to bend anything |
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New member Username: AlvingoPost Number: 5 Registered: Aug-05 | thanks for your help :-) your the best hehehe:-) |