Sealed Subwoofer Box Stuffing

Polyester fiber stuffing slows down sound waves inside the box making the subwoofer perform as if the box were bigger.

Sealed subwoofer box stuffing.

Learn all about how you can get more from your sub woofer using polyester fiber fill when your box is smaller than what the subwoofers air space recommendations are. In the case of the sealed enclosure the resonance frequency can be adjusted by adding or removing stuffing material from the enclosure. Damping treatments treating some of the surfaces of an enclosure can minimise or eliminate standing waves. After you install the subwoofers the enclosure will appear to be larger than it really is bringing you maximum sound quality.

The air doesn t flow in the box if it s sealed it just gets compressed and decompressed. Theoretically the effect is like having a 1 4x bigger empty box. Also if a program calls for a 1 cu ft box and your box is 1 1 cu ft and you stuff it with fiberglass etc. The sound wave coming off the back of your subwoofer reacts with the air contained in the box.

The effect of stuffing in the box is to absorb some of the heat which as you might imagine is the same as having a bigger box. Compressing heats it up slightly decompressing cools it slightly. If the frequency is right the reflected sound reinforces the radiated sound leading to a resonance. The effect of lowering qa is seen on the spl and impedance charts and in the box qtc.

A standing wave occurs when sound energy is reflected between two walls or a wall and the driver. I agree some stuffing is almost always helpful in a sealed box. A more accurate version of the above method involves using a resistor in series with the subwoofer system and connecting the multimeter set to voltage mode across the resistor. The purpose and advantages of polyfill in this article to ensure you get the best audio quality from.

It by no means is the same as making the box larger. Stuffing a ported cab upsets the box tuning lowers sensitivity and if sufficiently stuffed effectively changes the alignment from ported to sealed.