Audio Systems: subwoofer enclosure, dual voice coil, ohm impedance


Question
QUESTION: i am getting two 15"  15'' 4000 Watt Aluminum Die-Cast pyle Dryver Subwoofers, but i dont know what the box specifacations are. can you help me? and possible suggest an enclosure type?

ANSWER: Why do I think that a 15" speaker rated at 4,000 watts is for a car. Certainly in pro audio the only real ratings that go that high for a single driver are generally companies like EV or Aura. You should look at the fine print and see at what frequency, for how long and if that's a peak rating at what standard.

Pyle to my knowledge does not make high quality drivers. I would guess that their coils are wound with pretty heavy guage cable which would tell you a lot about what kind of sound to expect from it.

Any company worth their salt will be able to give you specifications for a cabinet especially because the drivers are designed to work in an enclosure (not in free space). Certainly you can go to sites run by JBL, EAW, Tannoy,and the like and either buy or download software packages that let you design an enclosure based on resonant frequency (Q) efficiency, size, compliance and size restrictions.

Anyone who can tell you off the top of their head what size enclosure to build, is a hobbyist.

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QUESTION: this is the information i could find about the subs

#  Custom Moulded Poly Cone
# Heavy Duty High Power Handling Driver
# Custom Grooved Rubber Surround
# Diamond Cut Aluminum Die-Cast Basket
# Dual Stacked Magnet Structure
# Chrome Mesh Magnet Vent
# 3'' 4 Layer Dual Voice Coil
# Moulded Plastic Gasket
# Spring Loaded Wire Connectors
# 4000 Watts Peak Power
# Magnet Weight: 2 x 100 oz.
# Nominal Impedance: Dual 4 Ohms

it says that the magnets are two 100oz.

can you suggest some brands that have a reputation for good drivers?
ANSWER: 4 ohm impedance cuts 4,000 watts down to 2,000 at 8 ohms. A peak power rating depending on the standard is generally 3 to 4 times the RMS. So what you have at best is a 1,000 watt speaker (more likely 500 watts at 100hz). A dual voice coil could mean that you need to drive it with two amplifier outputs. So that essentially if you drive a left and right channel in phase you will double the wattage.

What is this subwoofer being used for? What is the top end of your budget? Are you a hobbyist and want to build an enclosure just to say you built an enclosure? Is this for home, auto, club, theater?

I ask these questions because manufacturers more experienced then myself in enclosure design have been building these things for two decades. There is a subwoofer cabinet already fabricated to meet nearly any budget, size, coverage, SPL that you could want.

There are a plethora of systems out there. I will be happy to recommend based on your needs.

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QUESTION: i want to put a couple of subs in the trunk of my car. i have about six hundred bucks to spend maybe seven if i stretch it. im lookin for a quality enclosure that wont stretch or fall apart.

Answer
If you said that in the beginning I would have told you that it is not my expertise. Look at my credentials. Subwoofers for cars are mock audio. Nothing to do with the real world of audio because sub bass cannot be accurately reproduced in an environment that small. It takes 28 feet to produce a 40hz waveform. You need to speak with someone who knows only enough about audio to be an auto sound designer. I'm an engineer, I'm not that guy.