isobaric speaker boxes

[rockFord_Expedition]

You want to tackle isobaric design but don't know what xmax is. You have a lot of homework ahead bro. Best of luck.

[MotorCityFats13]

You want to tackle isobaric design but don't know what xmax is. You have a lot of homework ahead bro. Best of luck.

he also does not want to run @ 2 ohm because he loves 1 ohm! no mention of running 2 ohm is going to cut his power down a lot so what would be the point in running 2 subs on 1/2 power vs 1 sub on double power....

[ctq]

I have been out the game for a min yes when I was in sound heavy we had amps called punch and they was the shit do know the higher the ohm the less power that why am running the xfl 12 at 1ohm the plan was to buy another mb quart ra1000 and have one amp to speaker to keep the 1ohm load so what Ann saying one amp per speaker final build plan 2 american bass xfl 12 with 2 mb quart ra1000 one amp one speaker seems like I get more negative feed back for asking for help then actual help

[mcfalcon]

Look at it as constructive criticism . Gotta have a thick skin buddy. Now all that being said this isn't a forum that's gonna tell you to go to Best Buy and buy a prefab box. There is a whole lot more to box build than picking a tuning hz and using the manufactures reccomended size. There is a ton of information needed to help you build a PROPER box. If you are willing to provide this information and take advice that is given to you then you will not find a more knowledgeable and informative and helpful group.

P.S.

You were asked to use sentences and punctuation.

Show everyone you want to learn and you will be taught.

[diegoclass2010]

Triticum Agricolam what about xmax? Wouldn't that increase and help with low end response...

For reference I have no have no experience with these boxes and have read other threads where they explained the oversize boxes and decrease output potential in half... I'm just trying to think outside the box

Isobaric loading doesn't increase your xmax any, with a ported box xmax generally isn't what limits your low end response anyway (at least if designed correctly). What limits your low end response is power handling, which isobaric does help with, however there is a 3 db loss in efficiency going from a single sub setup to a two sub isobaric setup, so to make up for that loss you have to double your power, which puts you right back where you started from in terms of output and power handling. The only advantage of an isobaric setup is it reduces the size of the box. The penalty you pay for that size reduction is you need twice as many subs and twice as much power to get the same output.

gotcha now i get what your saying. now Triticum Agricolam let me trow you a curve ball so you say you can reduce the box, lets say we have space for a nice (2) 12 ported box and have left over space, but not enough for (4) 12 could and isobaric set up be consider?

now lets add power compression and heating issues into the equation, i would assume the the (4) 12's would dissipate it easier than to 12's, generally speaking it should be a more efficient

lastly for this example sub woofers have a 30mm xmax one way. isobaric set ups is a push pull situation between 2 subs so shouldn't it double since its now a longer throw one way shouldn't it double to 60mm?

im just trying to learn here

[Broke_Audio_Addict]

Isobaric= double the subs, double the power, and the same output you could achieve with one sub.

[Miguels]

[Triticum Agricolam]

gotcha now i get what your saying. now Triticum Agricolam let me trow you a curve ball so you say you can reduce the box, lets say we have space for a nice (2) 12 ported box and have left over space, but not enough for (4) 12 could and isobaric set up be consider?

now lets add power compression and heating issues into the equation, i would assume the the (4) 12's would dissipate it easier than to 12's, generally speaking it should be a more efficient

lastly for this example sub woofers have a 30mm xmax one way. isobaric set ups is a push pull situation between 2 subs so shouldn't it double since its now a longer throw one way shouldn't it double to 60mm?

im just trying to learn here

Basically what an isobaric system does is it lets you buy space and/or power handling. So using you example above, if you have enough space for a box for two 12" subs, you could replace that box with one using eight 12" subs (4 isobaric pairs). It would have exactly the same efficiency and same size as those two 12" subs did, but you would be able to put four times as much power to it since you have four times as many voice coils. Obviously that costs a lot of money to do though, it would probably be a lot cheaper and easier to just buy new subs that can handle that amount of power.

Another example is if you want to save space. Instead of having one 12" sub, you could run two 12" subs in a isobaric pair, they would perform the same as the single 12", but would only need half as big of a box to do it, but they will be 3 db less efficient. You could then double your power, to bring them back up to the same output capability, just in a lot smaller box, and with a lot lighter wallet.

Isobaric configurations don't increase Xmax, if you sub has 30mm of Xmax and uses all of it go get to 150 db or whatever, with the same sub in a isobaric pair, it still only has 30 mm of Xmax and will still use all of it to get to 150 db.

An isobaric config could help with power compression, which could gain you some performance, but there are always some losses with isobaric too so in the end its probably a wash.

[diegoclass2010]

nice write up Triticum Agricolam. hopefully this helps someone else .. examples help more .. still messes with my head... but ill just keep playing with regular boxes