Koliko Poly-Fill-a trebam za zatvoreni subwoofer 

Ako dizajnirate zatvorenu jedinicu subwoofera, onda vjerojatno znate koliko je važno napuniti kućište nekom vrstom materijala kako biste poboljšali vrijednost zvuka koji iz njega dobivate.

Ako se pravilno koristi, materijal za punjenje može poboljšati kvalitetu basa koji sabvufer isporučuje i njegovu opću izvedbu.

Međutim, prije nego što to učinite, koliko polifilla trebate za zatvoreno kućište subwoofera?

Trebat će vam 0,8 lb do 1 lb ili (12,8 oz do 16 oz) naboranog polifilla po kubičnoj stopi prostora u zatvorenom kućištu. Kao alternativu, možete dodati 1/2 lb odjednom do 1-1/2 funte.

U ovom trenutku trebali biste imati lijepo napunjenu kutiju koja nije zapakirana pretijesno ili prelabavo.

Uđimo u više detalja o polifillu i koliko će vam ga trebati za vaše kućište subwoofera.

Koliko Poly-Fill-a trebam za zatvoreni subwoofer?

Prije nego što uđemo u previše detalja, slijedite dva kriterija u nastavku kako biste odredili količinu punjenja koju ćete koristiti za kutiju subwoofera za poboljšanu kvalitetu zvuka.

1. Za kućišta koja su manja od 2,5 – 3,0 kubične stope, upotrijebite oko jednu i pol funtu polifilla po kubičnoj stopi vašeg kućišta. Nemojte prekoračiti ovu mjeru jer bi to moglo dovesti do prepunjavanja.
2. Za kućišta veća od 2,5 – 3,0 kubične stope, upotrijebite oko jednu funtu polifilla po kubičnoj stopi vašeg kućišta. Također, nemojte prekoračiti ovu mjeru kako biste izbjegli prekomjerno punjenje kutije subwoofera.

Dodavanje polifilla u kućište uzrokuje promjenu zračne opruge unutar kućišta iz "adijabatske" u "izotermnu". Punjenje kutije zvučnika polifillom, stoga, čini da se kutija čini većom pomoćnom vozaču. “Veća” glasnoća proizvodi dublji bas.

Štoviše, mala unutarnja glasnoća ponekad može biti glavni uzrok buke priključka subwoofera.

Izraz "adijabatski" koristi se za ilustraciju nedostatka prijenosa topline u mediju. Međutim, nakon dodavanja višestrukog punjenja dolazi do izotermnog procesa. Dok zrak prolazi kroz materijal s višestrukim punjenjem, njegova se vlakna pomiču i rezultiraju nekim oblikom rasipanja topline.

To se događa kada se dio energije koju stvara zračna opruga pretvori u toplinu. Na taj se način okolne molekule zraka zagrijavaju i zrak postaje manje gustoće.

Budući da zvuk putuje brže u gušćem mediju, subwoofer se odnosi prema kućištu sustava kao da je mnogo veći nego što jest. Učinkovito, polifill povećava veličinu kućišta zvučnika za preko 40%!

Uz ovu razinu povećanja veličine kućišta subwoofera, veća je vjerojatnost da ćete uživati ​​u mnogim prednostima proširene glasnoće zvučnika ili povećane razine basa. Neke od prednosti povećanog kućišta zvučnika uključuju:

• Proširenje povećava učinkovitost zvučnika
• Smanjuje SPL frekvenciju i tako nudi produženi donji dio. To smanjuje učinkovito prigušivanje zvučnika i čini vjerojatnije da će se smanjiti

S druge strane, previše polifilla može uzrokovati nekoliko izazova. For instance, over intensification of poly-fill causes the density of the material to increase so highly, that the fibers are no longer in a position to wiggle.

This way, the material loses its “size benefits, and the effective poly-fill volume reduces. Also, it is important to note that poly-fill is not very effective in supporting bass extension in speakers with large enclosures.

Is Poly-Fill Good For My Subwoofer?

Ever finished an enclosure that just sounded too boxy? You can hear unwanted reverberations, but you want to avoid the process of rebuilding the enclosure from scratch or you just do not want to.

You tuck in some poly-fill and the improvement seems extraordinary. You may not understand how it works or what it did, but you know the sound has improved. Maybe it’s the right time to learn more about it!

The white fluffy material, whether polyfill or fiberglass increases the interior volume of the subwoofer and makes it ‘think’ that it is in a much bigger box.

If you are looking to make a difference with improved bass, adding some poly-fill to your sealed subwoofer box will fix the issue.

Poly-fill is therefore a good choice for your subwoofer, especially if you intend to produce deeper low bass. Adding more poly-fill thus makes the bass deeper.

However, the quality of sound may reduce especially if the material is added in excess, but not too tight or loose. However, before you can make a selection, let’s look at the various types of fill.

Types Of Fill

The following are the main types of fillings used for subwoofer enclosures:

1. Polyester fiberfill
2. Fiberglass insulation
3. Long-fiber wool

Users with much more poly-fill experience recommend fiberfill as the best type of fill of the three.

It is easily available in local fabrics and crafts stores and is affordable. Besides, the fill is much easier to apply to the interior of your speaker enclosure.

Myths About Poly-Fill

Several myths about the use of poly-fill exist in the speaker industry. For instance, some audiophiles believe that poly-fill blocks standing waves within an enclosure.

However, regarding a subwoofer enclosure, and when you are playing a fundamental frequency that falls within the range of standing waves, this belief is incorrect.

This is because it is expected that a standing wave within the said range of frequencies should be very long – up to several feet. Therefore, there is little chance that standing waves will occur.

It is however possible that higher-order harmonic distortion will occur, and is much likely that it will color the audio.

Now because we expect that these higher-order harmonics will have shorter wavelengths, poly-fill will be very effective. Music clarity however changes and can be extremely low at high SPL.

Poly-fill and Harmonic Distortion

If you intend to use poly-fill as a remedy especially to absorb sound distortion or standing waves, it is important to note that it is only very effective in the large enclosures for midrange speakers, and is not for a subwoofer.

Does Polyfill Make Bass Deeper?

No. Polyfill does not make bass “deeper” by itself, it changes the tuning of a sealed system to allow for more low-end frequencies.

This is because bass frequencies require larger amounts of air, and a sealed box does not allow for the amount of air that is required.

To achieve more low-end bass without changing or upgrading your enclosure you need to add polyfill.

Can a Sealed Sub Box Be Too Big?

This can be answered with a simple ‘Yes’ or ‘No’. The answer depends on what you are doing.

If your goal is to make the subwoofer as loud as possible, then having a big box will do this.

A bigger sealed enclosure equals more air volume. This means that the subwoofer has more space to move air back and forth creating louder sound waves.

Therefore, this will end up causing a greater intensity of bass energy for listeners.

Thus making it seem like the sub sounds much better than smaller subs because there’s just so much “boom” being produced by them!

Does Sealed Subwoofer Box Size Matter?

Yes, the sealed subwoofer box size tends to matter. To find out how much polyfill you should use for your sealed subwoofer box, all you need to do is measure from the inside of the speaker location.

After that, add that amount of fill material in before installing your speaker.

This will make sure that your sound doesn’t become too boomy or wonky while giving off an accurate level response curve around the entire frequency spectrum.

Bottom Line

Poly-fill can be applied to both sealed and ported subwoofer boxes. However, there is no standard way of fixing the stuffing material as every audiophile will have their own preferences.

The right amount will always be the amount that sounds best, so take some time to add and subtract and ensure that you don’t pack it in too tightly and make sure it fills the entire space.

It is therefore more advisable that you apply a quantity that is within the recommended ranges but always make your sound preferences a priority.