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View Full Version : Builders... Designers... A topic to debate.



joeldirt
04-29-2006, 11:48 AM
A way while back... I used to construct all of my ported enclosures with each sub in it's own individual chamber. I spent allot of time ensuring that all of the measurements were equal to each side, and I mainly did it for the reinforced benefit from the center divider, as well as giving the sub it's own breathing air... After a long debate, I went to the popular vote of one large shared volume of airspace. I still remember how nice the boxes sounded, and after I went to the single shared airspace chamber design, I never really noticed any difference or improvement.... Now I am noticing that allot of people are designing, and building boxes with separate chambers.... Why is this? Was my old way acceptable after all??? Because I remember everyone thought I should step away from that design/ method, and go back to a single chamber.... None the less they both sound good to me... I want feedback on your guys' opinions, and why you choose or prefer this or that...

One chamber may be better for output... but what about sound quality? which would you choose? All considered that the box is built with accurate measurements and constructed equally proportionate.

One benefit I could see from one chamber is the easier design aspect for port usage... and that the subs are both pushing using the same port area... There is no chance of misaligned tuning frequencies...

loud-n-low
04-29-2006, 11:51 AM
i went from shared chamber to common air space,i feel as if seperate chambers sounded better

loud-n-low
04-29-2006, 11:52 AM
i meant seperate chambers to common air,seperate sounded better

LoudCrownVic
04-29-2006, 11:52 AM
Seperate chambers allow for wiring in series, and protect the subs, if one blows the other/s arent' playing in unacceptable airspace.

Other than that, sound wise I cannot comment.

joeldirt
04-29-2006, 11:57 AM
i meant seperate chambers to common air,seperate sounded better


That is what I argued before... And everyone fought me on it. I believe that box building is a science in some respect. Allot of math, allot of thinking, allot of theory, allot of allot of stuff is required to design/ construct a box when you really think about it... And I think that the people were fighting me, were the people that always took the easy route in building a box... It's just easier and it's allot less time consuming... (unless you are a pro the time difference wouldnt be that signifigant)

hofulstrof
04-29-2006, 12:01 PM
i perfer seperate chambers for the reasons mentiond above. but most ppl are tight on space and doing a shared chamber takes up just a bit less space **most of the time** in a shared chamber you can still wire in series.

it all comes down to personal preferance,shape of the box how much area you have to work with.

joeldirt
04-29-2006, 12:10 PM
i perfer seperate chambers for the reasons mentiond above. but most ppl are tight on space and doing a shared chamber takes up just a bit less space **most of the time** in a shared chamber you can still wire in series.

it all comes down to personal preferance,shape of the box how much area you have to work with.


I agree the most popular vote came from ease of design with space in the highest consideration... But I remember I was helping someone design and build a box on here over a year ago, and it was a dual chamber CRX box for two RE SE12's. Tuned to 32 I believe. We got started on it , and then he heard that building a box in two seperate chambers would not sound good.. Then I had a debate on this forum and the guy quit talking to me because the popular vote said that shared chamber is better, and that clearly I didnt know what I was talking about.. And that all of my experience was suddenly thrown away and deemed useless. That really pissed me off, and I have kind of just adapted my self to the market.. You can't build stuff ppl won't buy so I started doing all of mine single chambered... I don't like ignorance forcing a way of business. I felt like such a puppet having to change my individual style jus to accomodate people. It's like being forced to buy a hybrid vehicle that I don't wnat to buy, because gas prices are too frigin expensive to survive if I don't. It's like being forced into somthing because you can't survive if you don't just go with the flow. I much rather be unique, and put out the highest quality product...

PV Audio
04-29-2006, 12:45 PM
I have no personal preference. It really depends on how much room the customer has. For example, the enclosure I am building this weekend is a dual 12" type r enclosure. It has seperate chambers. The box I built LAST weekend was for dual L5 12's in a single chamber. The L5's were just mindblowing, and as I've made this type r design twice before, I know that they are just as enthralling. Personal preference and space requirements for me.

PowerNaudio
04-29-2006, 01:45 PM
if the enclosure is ported, i feel like there wont be that much diffrence . if the enclosure is sealed, i prefer having each sub in an individual chamber if youre using a two channel amp if youre using a mono amp to push both subs then single chamber for both subs is ok. since they will both recive the same exact signal.

LoudCrownVic
04-29-2006, 02:09 PM
:rolleyes:

Separate chambers don't offer any additional protection ...

Hmm, I guess youre right, once you think about it. Although it does make the box heavier so it's harder to steal... *** :)

James Bang
04-29-2006, 03:12 PM
:rolleyes:

Separate chambers don't offer any additional protection ...
wouldn't it? Say you're using a two channel amp w/ subs in the own seperate chamber, and one blows. The other will be perfectly fine w/ the same air-space and wattage. But in a single chambered enclosure, if one sub blew, the other will have 2x the airspace to work with with the same wattage, which would most likely be too much, since the airspace for that one sub has increased 100%. Wouldnt' that cause the sub to either bottom out or slam its motor?

for those reasons i would rather have a seperate chambered enclosure. But because I don't have room to work w/ I would go w/ a single chamber and watch my gains. ;)

joeldirt
04-29-2006, 03:17 PM
wouldn't it? Say you're using a two channel amp w/ subs in the own seperate chamber, and one blows. The other will be perfectly fine w/ the same air-space and wattage. But in a single chambered enclosure, if one sub blew, the other will have 2x the airspace to work with with the same wattage, which would most likely be too much, since the airspace for that one sub has increased 100%. Wouldnt' take cause the sub to either bottom out or slam its motor?

for those reasons i would rather have a seperate chambered enclosure. But because I don't have room to work w/ I would go w/ a single chamber and watch my gains. ;)


perfect response.

James Bang
04-29-2006, 03:25 PM
or was he being sarcastic, i dunno.

joeldirt
04-29-2006, 03:31 PM
or was he being sarcastic, i dunno.

no... I don't know.. But your response was perfect for the thread. I agree exactly with what you said.

I personally do separate chambers, but with space limitations I obviously go with a single chambered box.. I have one for two Immortal 12's getting 4800w RMS @ 1ohm ((If everything is running to exact specs. never put a meter on anything))that is 7ft3 at 38 hz... one chamber... loud as flipping shi*. But then again after choosing an Audiobahn Sub, regardless of it being their "top of the line SPL sub" there is no reason to even consider building a box for SQ. But 38 hz just so that I can still use it for everyday use.

Volenti
04-30-2006, 12:14 AM
There are instances where a multi chamber enclosure would have better SQ then a shared one;

Say we have a long enlcosure in a pickup housing 4x 10's sealed, it's ~4' long, if it was a shared enclosure you could have a standing wave problem ~70hz (4' is 1/4 wavelength of 70hz), if each driver was in it's own chamber the quarter wave frequency would be pushed up to well over 200hz, out of the band we are using the drivers for.

joeldirt
04-30-2006, 12:25 AM
There are instances where a multi chamber enclosure would have better SQ then a shared one;

Say we have a long enlcosure in a pickup housing 4x 10's sealed, it's ~4' long, if it was a shared enclosure you could have a standing wave problem ~70hz (4' is 1/4 wavelength of 70hz), if each driver was in it's own chamber the quarter wave frequency would be pushed up to well over 200hz, out of the band we are using the drivers for.

interesting...

hofulstrof
04-30-2006, 12:37 AM
There are instances where a multi chamber enclosure would have better SQ then a shared one;

Say we have a long enlcosure in a pickup housing 4x 10's sealed, it's ~4' long, if it was a shared enclosure you could have a standing wave problem ~70hz (4' is 1/4 wavelength of 70hz), if each driver was in it's own chamber the quarter wave frequency would be pushed up to well over 200hz, out of the band we are using the drivers for.
totaly forgot to mention this. yes good point

PV Audio
04-30-2006, 01:58 AM
Totally forgot to mention? I don't even understand what the **** he's talking about :(

hofulstrof
04-30-2006, 11:07 AM
edit

hofulstrof
04-30-2006, 11:09 AM
Totally forgot to mention? I don't even understand what the **** he's talking about :(
standing waves

PV Audio
04-30-2006, 01:39 PM
Oh, I am just not the shurpest nyfe in deh drawar.

James Bang
04-30-2006, 03:09 PM
1) What do you think the most likely cause of the first sub blowing was ?
2) Have you ever heard what it sounds like when one sub blows in a common-chamber enclosure ?

Answers:
1) Too much power
2) No, otherwise you'd know that you'd know right away if one of the subs were blown. In this case, separate chambers would offer you the convenience of being able to use the other sub(s) while the other one was getting replaced/repaired. However, this in no way means that it offers more protection, unless you have extremely slow reactions, are completely deaf, or are operating the sound system while being away from the vehicle.

On the flip side, if you're operating a separate chamber enclosure, you may not realize that one sub is blown and, since most people bridge their amplifiers and most amplifiers output more power per sub at a higher impedance, the likelihood of blowing the other sub would increase as well.

i.e.

500 w @ 4 ohm
900 w @ 2 ohm
1500 w @ 1 ohm

Two dual 4 ohm subs wired in parallel-parallel, each receiving ~750 watts. One blows, the other sub is now receiving ~900 watts.

tis why my example consisted of a 2 channel amp ;)

req
04-30-2006, 04:45 PM
i love you james :)

my only reason for having a dual chamber box would be for the benificial support lended from the added internal wall, and if i only had one sub at the time, but planned on upgrading to two in the future - or just that added idea of if one got stabbed by a air jordan in the back that only one sub would suffer mechanical damage due to circumstantial problems.

as far as how it sounds?

i believe it sounds exactally the same as a shared chamber.

James Bang
04-30-2006, 09:43 PM
And how many people run their sub amplifiers in 2-channel mode ? Maybe 1% of the forum members at best ?
If I were to change my setup, it would consist of an amp in two channel mode. before I do that i'll need to pick up a pair of IDs or IDQs run them off my ID amp ;) and put them in a seperate chambered box. :yumyum: