Silly's 1st Sub -- 8" MCM 55-2421

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I know, right? I just checked PE and they only have 2 10' passive radiators and one of them if far outside price range for this project.
I have no idea if the $25 Dayton PR they have would be applicable for this build or not

At that price point, it might just be better to spend the extra $5 and buy a second driver and follow this thread
http://www.diyaudio.com/forums/subwoofers/251016-cheap-sub-fantastick-results.html

Its bigger, but it still seems pretty nice
 
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Find a cheap 10 in woofer and add mass to it and short the leads with a power resistor for a tunable PR. Like this one: GRS 10PR-8 10" Poly Cone Rubber Surround Woofer

or this:

http://www.parts-express.com/goldwood-gw-210-8-10-oem-woofer-8-ohm--290-325

The mass addition and resistor shorting for damping can all be modeled. Cheap woofers tend to be floppy high Qts deals. Adding resistor electromotive damping will make Q lower.

Or you could just splurge and get the real PR for $26 - almost the same price as the driver.
http://www.parts-express.com/dayton-audio-sd270-pr-10-passive-radiator--295-494
 
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He he, you read my mind. That was exactly how I was going to build it. Being such a compact box, the 1 in thick XPS is plenty stiff and if you add a brace as suggested by Sreten it should be plenty strong. The tricky part is having a strong wood panel to mount the driver screws. I may just use small pieces of wood glued to the backside for screws to pull against.
 
Hi,

I think I've covered the the issues in the cheap sub thread.

However for PC extreme nearfield you can't expect or
use room gain, and a single driver in 7L to 10L well
stuffed sealed driven by a 4 ohm amplifier is as good
as any other starting point.

Basically you can then nearfield EQ it to whatever
bass extension you want, depending on the amount
of power available and the maximum volume needed.

A variation of the passive circuit here :
Baffle Step Compensation
Set to 10dB max and much lower
in frequency (50Hz) would work.
Or do it in the PC.

rgds, sreten.

You could make a ~ 400g PR using two 10" surrounds
and an appropriate thick sheet composite, like foamcore.

An externally hosted image should be here but it was not working when we last tested it.
 
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