In practice, damping is the ability of the amplifier to control speaker motion once signal has stopped. A high damping factor means that the amplifier’s impedance can absorb the electricity generated by speaker coil motion, stopping the speaker’s vibration. Other points: Damping varies with frequency.

Standing waves are formed when the reflection of a frequency in a room with parallel walls meets that same frequency coming from the source.

One quick solution is to use Dynamat automotive sound insulation to deaden the walls of the interior of the box. Dynamat is not thick, maybe 1/16 of an inch, and you just stick it to interior walls. It does not take up much volume.

Not just for insulating your house, adding polyfill to your subwoofer enclosure will do the trick. It’s a sound absorbing, dampening fiber that makes bass sound deeper. It provides a cleaner midrange while getting rid of unwanted reverberation.

Fiberglass used for insulation and stuffing of speakers should be the batt or blanket type which is bought in thick layers (1 to 4 inches thick) and can be rolled out. If concerned, just lightly spray the surface with some clear lacquer or possibly adhesive like 3M 77 spray adhesive.

On a more negative note, too much Polyfill can prevent your speakers or sub woofers from producing audio at their full potential. The correct amount can help bring out the full potential of your speakers and sub woofers, but too much will make them sound horrible.

If the enclosure is less than 2.5 – 3.0 cubic feet in size, you should use no more than one and a half pound of polyfill per cubic foot available in your enclosure.

You should probably just leave your klipsch alone they know how to get the job done with the least material at the lowest cost and in the safest manner. The foam in your speakers is fine and it works. You are more likely to make your speaker sound worse than better if you play with the damping.

Polyfill is like salt, it takes a certain amount for optimum benefit. Adding too much will reverse the effect and it is definitely audible.

If the volume is too small, it will dampen it too much. This will cause loss of frequency and introduce distortion. It will also reduce how fast the speaker can move – this also has many effects on performance.

Remember, there is such a thing as too big. As the size of the enclosure increases, the mechanical limits of the woofer will be easier to reach. If the box is too small (by a reasonable amount) add power. If the port becomes too small, it may result in port noise, or allow the woofer to simply unload.

10 inch drivers: 1.0 to 1.5 cubic feet. 12 inch drivers: 2.0 to 3.0 cubic feet. 15 inch drivers: 5.0 to 9.0 cubic feet.

The safest bet is a large sub with a lot of power. You’re much better off running a big sub at “4” than a small sub at “10.” If you want the best sound, multiple subs, in different locations in a room (or even just in the corners), almost always sound better and more realistic than a single sub.

Below tuning frequency the sub will become uncontrolled and unload and power handling drops. If the enclosure is too large the sub will unload anyway and power handling drops. Larger sealed enclosures make your woofer more efficient and give greater low frequency extension.

The sound waves are reproduced more accurately than with a ported enclosure but the subwoofers may require slightly more power from the amplifier to get the woofers to move as much as they would in a ported enclosure. Sealed enclosures are generally smaller and easier to build because there is no port to tune.

sealed or ported. I guess it depends on what you mean by “hit harder”. In my experience, ported boxes usually sound louder, but with sealed boxes, you feel the bass more.

There’s no rule that a smaller sub is something you can more easily use with music, or that you must have a larger one. I personally wouldn’t consider either of those subs suitable for music, or anything else really, unless it’s just all you can possibly afford.