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reed8857
11-27-2004, 06:41 PM
I am getting

2 x Alpine SWR-1241D (specs below) Powered by Soundstream VGA800.2 (Specs Below)


I will be wiring @ 2 Ohms RMS = 400 W each

In my searching it stated that I should build the box different from what the manufacture reccomends due to the increased wattage. However it does not state what would be ideal. What would be the ideal tunning freq? Should it be ported? Perferable I would like to keep the box simple with a sealed enclosure but if I can get better performance out of the Sub with ported than I will do it that way. Thanks for any help.

I listen to everything with rap being the most predominant

Specs: Alpine Type R (DVC..but you prob knew that already)
General-Subwoofers

Diaphragm Material : Kevlar Reinforced Pulp
Magnetic Weight : 89.4oz.
Mounting Depth (top mount) : 178mm (7”)
Mounting Diameter (top mount) : 275mm (10-7/8”)
Recommended Box Types : Sealed/Vented/Bandpass
Recommended Sealed Box Volume : 0.7 – 1.0 cu. ft.
Spider Material : Nomex
Voice Coil Diameter : 50mm
Power Handling

Power Handling Capacity (Peak) : 1000W
Power Handling Capacity (RMS) : 300W
Thiel Small Parameters

Coil Height (Hvc) : 37.74mm
Cone Area (Sd) : 467.59 sq. cm
D.C.Coil Resistance (Re) : 3.6 ohm + 3.6 ohm
Electrical Q (Qes) : 0.45
Equivalent Suspension Stiffness (Vas) : 58 liters(2.04cu.ft.)
Free Air Resonance (Fs) : 28Hz
Frequency Response : 24Hz - 1kHz
Gap Height (Hag) : 10mm
Impedance (Nominal) : 4 ohm + 4 ohm
Inductance (Le) : 3.85mH at 1kHz (1.34mH at 20kHz)
Linear Excursion (X linear) : 13.87mm
Maximum Excursion (X peak) : 27.7mm
Mechanical Excursion (Peak-to-Peak) : 55mm
Mechanical Q (Qms) : 8.31
Sensitivity : 87 dB/W/M
Total Loudspeaker Q (Qts) : 0.43


Amp Specs

Output(Watts) RMS @ 4 Ohms: 200W x 2
Output(Watts) RMS @ 2 Ohms: 400W x 2
Output(Watts) RMS Bridged @ 4 Ohms: 800W x 1
THD: < 0.02%
Signal to noise ration:: > 115dB
Input Sensitivity (Volts): 0.15 - 12.0
Crossover Slope: 12dB
Crossover Frequency: (Hz) 30 - 4k
Dimensions(INCHES) : 11.2" x 2.6" x 16.5"
RUBI (Rapid-Use Branched Impulse) proprietary power supply topology
STACT (ST abilized Apex Current Topology) Reduces power supply stress by 50%
Trident Amplifier protection topology
Hawkins Bass Control Proprietary bass equalization topology
IDI (Intelligent Distress Indicator) gives visual indication of amplifier
protection status
Harmonic Bass Alignment produces tighter, more accurate bass
Fully regulated MOSFET power supply
Triple Darlington Output Circuitry
BIP (Bias Input Protection)
Rail Stabilization Protection Circuitry
Bi-linear selectable two-way crossovers for amplifier and line outputs
Continuously Variable High and Low Pass Crossovers
Balanced Line Inputs for the Highest level of Noise Rejection
Vortex Induction Fan for Thermor Management
Platinum RCA Inputs and Outputs
Platinum 4-gauge Power Connectors
Tri-mode Operation

bonesninja
11-27-2004, 06:44 PM
imo--go with the sealed box--you can give it more than the recommended rms if you a sealed enclosure. thats as simple as it gets

reed8857
11-27-2004, 06:48 PM
should i make it bigger? if so how big? and thanks for the repsponse.

bonesninja
11-27-2004, 06:50 PM
i would go about 1 cube per sub---but ask one of the box builders in here like JMAC or BIA BIA

jellyfish420
11-27-2004, 07:32 PM
imo--go with the sealed box--you can give it more than the recommended rms if you a sealed enclosure. thats as simple as it gets
power handling is greater in a ported enclosure around tuning...

jellyfish420
11-27-2004, 07:36 PM
if they were mine i would go 1.5-1.75ft^3 per tuned around 30Hz.

bonesninja
11-27-2004, 07:42 PM
well he said he would preferably like to keep it simple and sealed but if he could get better performance---his definition of better may be different than me or you so thats why i recommended the sealed box--he pretty much answered his own question. but you can get awesome with either ported or sealed just depends what kind of bass your lookin 4.

reed8857
11-27-2004, 07:42 PM
ok time for a dumb question.......wait there are no dumb question.....just dumb people asking quetions.....anyways when someone says there going to tune does that imply that it is a ported box?

reed8857
11-27-2004, 07:43 PM
I am all about different ideas the more info I have the better decision i can make

JimJ
11-27-2004, 07:44 PM
anyways when someone says there going to tune does that imply that it is a ported box?

Yes, you're correct.

reed8857
11-27-2004, 07:55 PM
Ok, I know sealed is better qaulity and ported make it louder....I know its a little more complicated than that and alot has to do with personal preference. still, knowing what I just said can anyone give me the advantages to your paticular suggestion for a box....2 sealed, 1 ported. thanks

reed8857
11-27-2004, 08:01 PM
sound good to me was hoping I was not going to make a mistake, already worry enough about giving the sub more than recommened

bonesninja
11-27-2004, 08:05 PM
sound good to me was hoping I was not going to make a mistake, already worry enough about giving the sub more than recommened
i would listen to jmac--everyone else does--i'm trusting him to design my box

reed8857
11-27-2004, 08:06 PM
Yeah I have already figured him to be a more repected opinion on this forum

reed8857
11-27-2004, 08:16 PM
actully the subs are rated @ 300w RMS unless I am missing something?


400 going to them rated @ 300w RMS = more than 38 over

reed8857
11-27-2004, 08:18 PM
oh......thanks

reed8857
11-27-2004, 08:22 PM
According to BBP6, each Type-R should be able to handle up to 510 watts each in the 1.25 ft^3/sub enclosure (mechanically, before exceeding Xmax) ... Only 415 watts each in the 1.5 ft^3/sub enclosure (mechanically) ... 680 watts @ 1 ft^3 ...[/QUOTE]

took me awhile to figure this part out...but i get it now

reed8857
11-27-2004, 08:36 PM
should it be chambered? last ? I promise...lol

reed8857
11-27-2004, 08:46 PM
cool thanx JMAC