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Discussion Starter · #1 · (Edited)
Please help me design a passive radiator enclosure for my 2 Cerwin Vega VMAX15.2 drivers. Power is coming from a pair of BASH 500 plate amps and signal will be optimized by Audyssey in a receiver or separates yet to be purchased.

I'm not fond of sealed boxes but last time I attempted to spec a ported box for these TLS Guy pointed out a few critical downfalls of a vented enclosure for these drivers.

With all this in mind I'm considering a compromise Passive radiators. I've attempted to model an enclosure with passive radiators in WinISD but am having trouble. Anyone out there have knowledge and experience designing passive radiator enclosures? Would my drivers even work well in this type of enclosure? I have a fairly large room so a single enclosure with both drivers and radiators is possible even if the volume reaches the 10 cu ft + neighborhood. Although I think 2 separate enclosures would fit the room a little better.

Here are the driver parameters (Thanks for the help!!):
Name: VMAX 15.2
2 coils
Nominal Impedance: 2 ohms
Sensitivity ([email protected]): 87.3dB
Power Handling RMS: 600 watts
Voice Coil Dia: 2 1/2"
Mounting Dia: 14 3/32"
Mounting Depth: 7 1/8"
Spkr. Displacement: .22 cu. ft.
Fs: 22.6Hz
Qts: .47
Qms: 4
Qes: .53
Vas: 2.9 ft3
Xmax: +/- .8"
Revc: 1.32 ohms
 

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You'll get the most output from these in a 24" cube which would be about 6.2 cu.ft. net volume.

If your BASH 500 plate amps came from Parts Express then they have a subsonic filter at 30 hz, this will have to be modified to a lower frequency if these subs are for home theater use.

Which PR's were you looking at?
 

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Discussion Starter · #3 ·
Thanks for the reply Mike. When you mention the 24" cube as the optimal enclosure, are you meaning sealed?

I don't really have a good source for PR's. Can you make any recommendations? I've looked at a few from Parts Express, as well as Earthquake but without really knowing how to model and test how the PR's will effect response I'm not sure how to approach this. Is it good practice to just randomly select a PR to input into a boxbuilder program then see what it spits out?

My BASH amps are from Parts Express. I had no idea about the 30Hz subsonic filter. Any advice on how to remove/bypass it?
 

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When you mention the 24" cube as the optimal enclosure, are you meaning sealed?
No, that would be optimal for ported or PR.

Modeling PR's is all about finding a PR that will have enough excursion for your driver/cabinet/amp combination. I'll post a couple of PR options in a few minutes. (windows 8 is giving me grief, have to reboot.)


 

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Changing the hi-pass filter on the amp involves changing out 2 resistors. The values are in the PDF. For your use a HPF at 18.7 hz from the 1 db of boost table would be best. Click on the first link under Manuals/Resources.

http://www.parts-express.com/pe/showdetl.cfm?partnumber=300-752

Purple would be a with a pair of CSS 12" PR's, they would be at their maximum excursion capabilities.
Orange is with a pair of CSS 15" PR's, a much better choice in my opinion.

Here are the project files for both.

View attachment VMAX15 12 PRs.wpr

View attachment VMAX15 15 PRs.wpr

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