Help with 12" sub design for donation!

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Hi GM,
the ft cubed/ litre conversion that I gave was just an instantaneous guess so thanks for the exceedingly accurate calculated conversion.
So far, with the drivers I have, an isobaric pair in a passively loaded box seems to be the best option. Isobaric, to help reduce the box volume and passive radiators to make the EBS alignment easier to implement.

As far as whether to wire the drivers in series or parallel, I think series will be safer with regard to the already low impedance. I do not have a manufacturers Xmax and have yet to measure the inductance. ( the L facility of my L/C meter has died ) The only T/S parameters I have are in my first post. They drivers were made by IPL (UK) I thought they looked good on paper and at the price they were on sale for.
I agree with you about the excursion of the passives, in that there is a risk of them bottoming out so I am thinking of looking out for another pair which will give me three for each box, which should be ample! They will need loading with quite a bit of mass to drive the resonance down sufficiently for an EBS alignment.

Got to go to work

Cheers
 
Now, now, be nice! I just copied what my Excel spreadsheet spit out.

Agreed, assuming your amp's not rated for a 2 ohm load and the driver's inductance isn't too high.

I'm curious, where did you get the specs? I couldn't find them here or in a search: SEAS DRIVE UNITS

If your drivers look like the woofers shone on the link, then HiVi’s F12 look-alike’s 6 mm Xmax seems a reasonable assumption, so hope you have a fair amount of room boundary gain to boost the low end.

GM
 
Hi GM,
I'm always nice! Or, at least, I never intend to be otherwise!
The amp that I will be using, will be 2 ohm stable, but I guess it will be better to be cautious.
You will not find the drivers on a search ( well, I doubt it very much ) They were only available from IPL for a while as a clearance sale. They were £15.00 each so I could not resist giving them a go. Maybe they will not be up to much, but the specs read well. They have double magnets and good efficiency so it's worth giving them a go. They do have a high VAS, hence the isobaric set up to help reduce box size.
My main aim is to get a response that can get somewhere that Linn Isobarik's can. I do not need to get really high volumes so excursion should not be too much of an issue if I do not try and get too low. If I can get -3db at 30-35 Hz I'm sure that will be fine. It's all in the listening of course.

Cheers
 
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