Sandbags on sub--cheap, works great

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When I built my current subwoofer, I thought that it was a monstrous thing that would be totally free from box resonace due to it's extreme weight. Consuming a full four sheets of 3/4" MDF, as well as other wood for various bracing features, it weighs over 240 lbs, without the driver installed. The driver is a single Infinity Perfect12 (car subwoofer), and has two Avatar Audio 15" passive radiators, loaded with expoxy and lead shot. The box is a pretty basic rectangular shape, and has four large, sharp, metal spikes on the bottom which penetrate my carpet and rest directly on the concrete foundation. It's driven with a NAD 214THX Amp, in bridged mono configuration.
I was always impressed with the unit's ability to play extremeley low tones (even down to 5 hz) with an insignifigant drop in Db. In fact, the -3 Db cutoff is below 10 hz. (Of course, the price for that is that this thing is HUGE). However, I've been somewhat dissapointed in the "speed" of the response sometimes--though it's been improving steadily the more the woofer gets "broken in". I decided to try out the mass adding trick becasue it was easy and cheap to.
I made three sandbags from canvas, which I purchased from the local fabric shop. I filled each one with 70 lbs of regular "multi-purpose sand", from the home center. The total project cost was $22, which included sand, canvas, heavy-duty thread, and needles for the sewing machine. After about an hour's worth of work, I had my sandbags. I placed them on top of the sub, and sat down to listen.
The results were nothing short of amazing. The "punch" and "attack" of the bass tightened up a lot. As well, the clarity of low synthesizer tones and the like improved greatly. My concerns about "Speed" almost disappeared. Overall, the improvement was unbeliveable for the measly sum of $22.
I suggest that all you fellow lunatics out there with deep-bass subwoofers try a similar tactic. It worked wonders for me.
Allan

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Topic - Sandbags on sub--cheap, works great - Allan Moyse 11:23:33 05/13/00 (11)

Re: Sandbags on sub--cheap,What size box? - jim 12:56:36 05/14/00 (4)

Re: Sandbags on sub--cheap,What size box? - Allan Moyse 13:42:49 05/14/00 (3)

Re: Sandbags on sub--cheap,What size box? - jim 14:01:43 05/14/00 (2)

Re: Sandbags on sub--cheap,What size box? - Allan Moyse 15:41:43 05/14/00 (1)

Re: Sandbags on sub--cheap,What size box? - jeffk 16:26:43 05/23/00 (0)

scrambled or fried.... - dave c 15:42:59 05/13/00 (5)

Re: scrambled or fried.... - Bob Samuelson 16:18:25 05/13/00 (4)

Re: scrambled or fried.... - Aragorn 05:01:14 05/14/00 (2)

Re: scrambled or fried.... - Bob Samuelson 09:06:32 05/14/00 (1)

Re: scrambled or fried.... - Aragorn 19:32:42 05/14/00 (0)

Re: scrambled or fried.... - Allan Moyse 18:02:56 05/13/00 (0)

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