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TRANSMOTIONAL  INSERT
 

In this animated illustration, you can see the adjustable insert in three possible positions.

FREQUENCY RESPONSE OF DIFFERENT POSITIONS

 

This is the actual response test done on each of the three positions above.

The Death Box was originally a study in power handling.  We studied why woofers blow up, especially in band pass boxes and in the process optimized a design to minimize the negative effects of abuse.

 

I guess you can tell we were in the car audio business! This process of seeing how far we could take a 10 inch woofer and what the causes of failure were, is how the box got it's name.

 

We built and tested over 80 revisions of the classic band pass box to improve power handling and SPL.  This lead to eliminating the typical port and replacing it with a symmetrically perfect duct system that kept internal pressure evenly distributed on the woofer cone.

 

We also found cabinet resonance would excite the woofer in negative ways and reducing them improved performance.

 

Adding a restriction to the duct assembly outlet created a duct that would now resonate across a wider frequency band (like a vero-vent) and that improved power handling again.

 

Creating a fixed symmetrical duct / baffle assembly that was transmotional allowed the circuit to be optimized for different woofers and tuned in its final destination, the room or car.

 

The resulting transmotional duct system yields symmetrically even pressures on the speaker cone, hence we named it SCD (Symmetric Compensation Design). 

 

A secret to successful car audio systems is of course your subwoofer, or foundation. Understanding that a car is not a living room, but rather a box is the first step to understanding cabin gain. When you put a box in a car, you are actually putting a box inside a bigger box, thus creating additional orders. Because of this reactive capacitance all around your box, having two 12" woofers openly firing into the car is usually asking for all kinds of performance variables. This is the reason why one enclosure will sound good in one car, and terrible in another. 

 

We have determined that to minimize these loading problems, and to allow an enclosure to breath freely, it must be consistent with a small box to room ratio of less than 15%. It is also desirable to control the air space in front of the woofer by removing the capacitance created by flexing metal in your trunk. This is why we chose a band pass design to begin with. 

 

There are currently copies of this box being marketed that do not employ SCD technology, are not transmotional, and are not able to be tuned to your choice of subwoofer and car. Needless to say the results are inferior. DECWARE makes the only original Death Box. 

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