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difference between using recommended enclosure specs and smaller or bigger?


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26 minutes ago, 1point21gigawatts said:

I’m gonna reference the numbers of the new enclosure in multiple programs and calculators before I draw up a cut sheet.

Sounds good. From my analysis..the main thing that will be changing is the tuning will slightly decreased 2hz maybe and the net airspace will be increasing roughly half a cube. As long as this will make a noticeable audible difference than the box i have now then its all good. if you need to tweak anything, as long as it stays within my max dimensions, then go ahead. im willing to raise tuning a lil if a bigger port is necessary and if you think that would sound better..

Edited by akuma4u
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On 7/28/2020 at 10:03 PM, 1point21gigawatts said:

When you gather information from all over the place and don’t use that information correctly to weigh right from wrong then it’s easy to become confused and indecisive about a matter. I skimmed through them screenshots and seen facts and fiction and didn’t even have to study it and keep reading it to asses the general knowledge from it. If I were a noob that didn’t know how to build enclosures, I could use that information you posted and come to a conclusion quick because I’m smart. If you do the mathematics on the port area of both enclosures I told you to choose from, one has 12.3 square inches of port area per cubic foot and the other has 16 square inches of port area per cubic foot. That’s kinda what was told to you in the screenshots you posted. And 2.3 cubes is 15% bigger than 2 cubes that’s recommended. That’s not enough of an increase to cause the subwoofer to reach its mechanical limits and bottom out and damage the subwoofer. That’s 5-10% less than the maximum increase before bottoming out would occur and the amp would have to be stronger to cause that on that subwoofer. You have understand each subwoofer is different and designing an enclosure has to be done by factoring in the t/s parameters. The recommendations of sizing is just a basic idea. And when it comes to port noise, the more the rms and lower the tuning, the wider the port has to be to not have port noise. More rms increase port velocity and lower tuning increases port velocity. Some designers and builders use less port area to accommodate for the area available when building an enclosure with a lot of subwoofers and it helps with bandwidth and accuracy depending on the application and design, but takes away from the output. As long as it isn’t a crazy amount of port area, the bandwidth would be fine and it wouldn’t reach mechanical limits. That why I suggested an spl slot port enclosure with 16 sq” per cube and a musical aero port enclosure with a little less than 12.3 sq” per cube. And a 15% increase would increase output without reaching mechanical limits. Most pros that compete increase the sizing of their enclosures by 10-20% to increase output and they throw more than rated rms at the subwoofers. Plus recommendations about sizing is just to reference. You have to factor in the t/s parameters of the subwoofer and the rms of the amp. That amp 2400.1 you are using isn’t doing 2000 rms after rise. Rise differs on each frequency, subwoofer and application and cabin area surrounding said enclosure. Dude just messaged me earlier today and he is rising from 1 ohm to about 4 or 5 ohms and on a bass 30k only doing 9000 rms. So a 30,000 rms amp is only doing 9,000 rms after rise on his set up on whatever frequency he tested it on with an amm-1. So with that said, the enclosure has to be bigger because you are probably doing around 1000 rms. That figure is based off of the specs of that amp and the absolute lowest rise if the subwoofer, application and cabin area surrounding it permits minimal rise from about 1 ohm to 2.5 ohms. Rising from 1 ohm to 2.5 ohms is minimal rise and would make any bass head happy as shit. Before I begin to type or draw something up, I learn every piece of the equation and factor in so many different variables and calculations and base the variables off of facts and if facts are unavailable and it’s something like impedance rise, I would factor in the best possible scenario when it comes to that when designing an enclosure because if I calculated using the worse case scenario of impedance rise then it would leave too much room for error. Factoring the best case senecio leave no room for error when it comes to that variable. Then on some variables I have to factor it worse case scenario to ensure no errors arise. Averaging is something that works with some things but averaging can be problematic if something in the equation is below average or below average.

i didnt even realize you made this big ass reply until now. If you were a noob, how would you be able to tell between fact  and fiction? thats right. you wouldnt. because you are a noob and dont know what is fact from fiction. which is kind of the situation I am in. I have a general understanding of enclosures and am still learning by way of building different boxes and playing around with port area and size etc.. its expensive to do this but i have no choice really.

gathering information is what ive been doing and do often on this site and other sites , it saves me from starting multiple new threads.

Regarding the box size and increasing it, yes this works from what i understand when people are on low power.. BUT lets say you have ample power or are overpowering,. lets forget about rise for a minute,. and you put this extra power to a sub in a larger than recommended box... is that potentially dangerous? I ask this because i found a user who used low power on a zv3 12 that was in a 2.3net box, which is prob quite similar to what i designed and check out his response (the screen shot will follow underneath) what do you make of that?

 

i think in the end i will be building 2 boxes,. the one i designed which you are going to be sending a cutsheet/blueprints of the 2.3net box.. btw, how are the calculations coming along?

and i will be building a 2nd box 2 cubes 32hz with 24 sq inches of port.. i wont be building this 2nd box until i build the 1st one as the 1st one may satisfy my needs to the point i dont need to do a 2nd box..

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Your enclosure now is already small and you want louder and harder hitting bass on the same rms, which is minimal rms after rise for that subwoofer. The only thing that can be done in this case is increase the net volume. You are thinking too hard into this. And that straw and toilet paper tube analogy wasn’t used correctly. Of course more air velocity is generated throw a smaller tube on the same amount of rms. But if the rms is too high for that tube’s diameter then there would be port noise because the air would be traveling too fast. You don’t want high port velocity. You have to stop looking too hard into this because you are gonna keep running into contradictions and become more indecisive.  

Edited by 1point21gigawatts

:stupid:“How can we help you?”
:guido:
“And don’t forget to tell them that 
the customer isn’t always right.”

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1 hour ago, 1point21gigawatts said:

Your enclosure now is already small and you want louder and harder hitting bass on the same rms, which is minimal rms after rise for that subwoofer. The only thing that can be done in this case is increase the net volume. You are thinking too hard into this. And that straw and toilet paper tube analogy wasn’t used correctly. Of course more air velocity is generated throw a smaller tube on the same amount of rms. But if the rms is too high for that tube’s diameter then there would be port noise because the air would be traveling too fast. You don’t want high port velocity. You have to stop looking too hard into this because you are gonna keep running into contradictions and become more indecisive.  

as i said im willing to build the bigger box, just waiting for the cut sheet/blueprints

 

those screenshots i thought it was worth showing you as that one dude said he used a 2.25 net enclosure on his zv3 12 on LOW power and was able to hit the backplate easily.. which means he reached mechanical limits on low power easily.. i thought it was worth noting.

 

regarding port noise, audiofanatics said that steve meade is using like 6 15s and like only 8-10 sq inches per cube and its very small port area for those subs and you would expect port noise but there is none at all and its violent.. i thought this was also worth noting as its proof that a over doing it on port area isnt always necessary and using little will not always cause port noise. I think this is worth noting as it is a great example. This is also why i showed the screenshot of the owner of sundown recommending only 12 sq in per cube... that is the same thing EMF audios owner told me to do..

 

anyways. in the end im going to be building 2 boxes.. the 2.3net enclosure will be first and hopefully it will turn out so good i wont need to build the 2nd one.

 

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