[yogesh]

I havent auditioned any of those speakers or subs but judging from your HU choice I am sure it must be an awesome setup. Btw can you tell us how much you paid for the HU??

[yogesh]

Originally Posted by navin

you could have gone for a push-pull isobarik.

navinji what would be the enclosure volume if he had gone for a push-pull isobarik setup??

[Bass&Trouble]

Originally Posted by navin

I think LBM was joking. The moment you mentioned Kicx we knew where the install was done, right B&T?

Thats the only place in the universe I know of, where it is sold. Hence I asked.

Originally Posted by navin

Rtech, you see the Vb is so small that is the woofer was mounted facing out the woofer's volume would have eaten into the Vb and made it even smaller.

?

Box volumes are specified either after accounting for driver displacement or without. So you can build a box that accounts for driver displacment, and the additional volume required. The only time when you have to mount a sub inverted is either when
1. The box volume required is so small that it is almost the same as the driver displacement (very very unlikely) and hence boxing it involves building a conical structure around the sub, this will cause the rear of the sub to be too close to the rear wall, or
2. when the enclosure has a depth restriction. So its a regular volume enclosure, but wide rather than deep. And maximum depth at any point is lesser than the mounting depth of the sub. Which is the case here.

Originally Posted by navin

EVO6, you could have gone for a push-pull isobarik.

?? If he did push-pull isobarik, one of the subs would have to go into the enclosure. If he can't do that with single driver sealed box, how will he manage it in isobaric. Secondly, for the exact same respone in isobaric as that with two subs in simple sealed box, the box volume would need to be half! So half of what he has now???

[Technocrat]

Can some one explain in layman's laguage what does this Isobarik thing mean ?

[navin]

Originally Posted by EVO6

When you sam and the other pro's are around I know that we all are in good hands..

Correction. I am NOT a Pro. I do not belong to the audio fraternity in that I never have represented, worked for, or dealt in any audio equipment or represented any publication related to this industry. Like you, I am just an interested bystander. Sam, B&T, Gunbir, Autophile, Blueraven, etc. are the Pros. I just happen to a moderator who has been entrusted with the ICE forum.

Yet as "intrested bystanders" I believe we (guys like Hydra, LBM, yourself, myself etc...) ca also provide a lot of service as we are not influenced by our affiliations. Personally, I would love to see more of you on the ICE forum.

[hydrashok]

In an Isobaric setup, two subs (sub-drivers) are installed face to face (that is, uh, cone to cone). One of the subs will be in a proper sealed enclosure. The other sub will be outside the enclosure, and it's "face" (the cone side) will bolted onto the "face" of the sub in the enclosure. This uh.. fixing will be air-tight. And the drivers will be wired out-of-phase of each other. That is, if one driver is pushing outwards, the other driver will be pulling inwards.

This design is used when space for enclosure is at a premium. This design apparently give the same results with half the enclosure size that would have normally been needed.

The sub-drivers used for this must be identical drivers. I guess (not sure about this) the setup will need about double the power as two drivers would need to be fed. But the output will be the same as if a single driver were used with double the enclosure size (of the isobaric setup).

I've never seen one of these (not that I've seen a whole lot of the others ), not even in pictures. I'd love to listen to one of these setups sometime.

I guess they are not so popular as they cost about double what it would cost to get a single driver in a single enclosure, powered by a regular amp (that the single driver needs to perform well).

[Technocrat]

Thanks hydra, that was quite informative Hmm but I really wonder how many would actually prefer that, I mean won't EVO's setup sound better than the isobarik one? (I am saying as i have heard his)

[low_bass_makker]

here are some graphical representations on the isobarik loading.....







taken from.....

Isobariks Tuturial

[Bass&Trouble]

Originally Posted by hydrashok

In an Isobaric setup, two subs (sub-drivers) are installed face to face (that is, uh, cone to cone). One of the subs will be in a proper sealed enclosure. The other sub will be outside the enclosure, and it's "face" (the cone side) will bolted onto the "face" of the sub in the enclosure. This uh.. fixing will be air-tight. And the drivers will be wired out-of-phase of each other. That is, if one driver is pushing outwards, the other driver will be pulling inwards.

This design is used when space for enclosure is at a premium. This design apparently give the same results with half the enclosure size that would have normally been needed.

The sub-drivers used for this must be identical drivers. I guess (not sure about this) the setup will need about double the power as two drivers would need to be fed. But the output will be the same as if a single driver were used with double the enclosure size (of the isobaric setup).

I've never seen one of these (not that I've seen a whole lot of the others ), not even in pictures. I'd love to listen to one of these setups sometime.

I guess they are not so popular as they cost about double what it would cost to get a single driver in a single enclosure, powered by a regular amp (that the single driver needs to perform well).

Splendid!

Just one thing to bring to your notice. Isobaric does not always need to have subs mounted face to face i.e. clamshell, push-pull, in which subs are wired in reverse polarity, they can also be back to back (reverse polarity), or front to back (correct polarity). Idea is to have a volume of constant air between the two subs - hence 'isobaric'.

[hydrashok]

Originally Posted by low_bass_makker

here are some graphical representations on the isobarik loading.....

Originally Posted by Bass&Trouble

Isobaric does not always need to have subs mounted face to face i.e. clamshell, push-pull, in which subs are wired in reverse polarity, they can also be back to back (reverse polarity), or front to back (correct polarity). Idea is to have a volume of constant air between the two subs - hence 'isobaric'.

Cool! I knew only of the first type! And even a ported design is possible!

And what about the power requirements? Do we need to feed double the power as there are 2 drivers (I guess so...)? Or just the amount of power needed for a single driver?

[navin]

Originally Posted by Bass&Trouble

?? If he did push-pull isobarik, one of the subs would have to go into the enclosure. If he can't do that with single driver sealed box, how will he manage it in isobaric.

ofcourse it would require a different box design from the present one.

[navin]

Originally Posted by hydrashok

And what about the power requirements?

a-ha there is no free lunch not only do you need twice the power but you also get half the sensitivity!

[hydrashok]

Originally Posted by navin

a-ha there is no free lunch not only do you need twice the power but you also get half the sensitivity!

Double the power, double the no. of drivers and so double the cost! And half the sensitivity after all this.

An Isobaric setup must sound really really good for somebody to go for it. Now I really have to listen to one somehow.

[determinus]

Originally Posted by hydrashok

An Isobaric setup must sound really really good for somebody to go for it. Now I really have to listen to one somehow.

Next time you are in Pune, drop by. I have isobaric sub in my HT, made by Torvin (Chennai based guys, makes pretty decent stuff). The setup is push-pull or cone-to-cone. Each drive is rated 80w RMS, I drive it using a Yamaha 870 (85x2). The enclosure size is 3'x2'x2.5'. Not sure if they still sell it.

[Technocrat]

Why dont we have ICE meet for Pune guys