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Old 22nd April 2012, 01:46 AM   #11
GM is offline GM  United States
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I don't have any MJK software to sim a double BVR, but at a glance I'd start with ~5.52 ft^3 net/35 Hz Fb.

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Old 22nd April 2012, 02:08 AM   #12
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I don't have any MJK software to sim a double BVR, but at a glance I'd start with ~5.52 ft^3 net/35 Hz Fb.

GM
i'm trying to stay within the 1mm threshold i've set to get reasonable listening volume and enough bass extension to 'blend' in with the sub. designs that go that deep always seem to nuke the budget before any real noise level is reached.

i took on board what you said about being flat from 60hz - 300hz then rounding off to 40hz and tried to find a compromise of that brief based upon my current incompetence.

the curvy one gets me down to 70hz flat(ish) then has dropped 5db by 50hz.
90db simulated @ 50hz, above the bass range it sims flattish @ about 93-95db @ 1watt. if i take it up to the 1mm excursion limit i placed on the design that adds nearly an extra 10db to the numbers. is this a reasonable compromise of your previous design brief?

the sub sims fairly flat from 28-90hz @ 98db for 1 watt. i was thinking that the combination of the 2 would be enough?

thanks for your help

Last edited by gafhenderson; 22nd April 2012 at 02:10 AM.
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Old 22nd April 2012, 02:57 AM   #13
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I forget what all I've posted as you've started a number of threads only to abandon them, but IIRC I posted that you ideally want at least an octave of ~flat BW on either side of the XO point, so this requires a good size cab/low tuning plus this high a Qts driver really wants a much larger cab tuned even lower to keep it from sounding 'boomy'/'loose', which will ripple up through the BW even limited to 1 mm if not fairly well damped with stuffing. For sure, the posted sim XO'd to a sub wouldn't sound good in my acoustically larger than average room.

With a sub covering up to at least 60 Hz, its overlapping BW will help with the power handling and probably allow another 10 W or more to reach the 1 mm limit.

Dunno, you don't ever post any useful design data, but short of stuffing the @#$% out of it, I don't see how this driver can be flat enough in any high tuned cab, especially a BVR, which IMNSHO is a waste of time/materials for this app.

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Old 22nd April 2012, 04:10 AM   #14
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Originally Posted by GM View Post
I forget what all I've posted as you've started a number of threads only to abandon them, but IIRC I posted that you ideally want at least an octave of ~flat BW on either side of the XO point, so this requires a good size cab/low tuning plus this high a Qts driver really wants a much larger cab tuned even lower to keep it from sounding 'boomy'/'loose', which will ripple up through the BW even limited to 1 mm if not fairly well damped with stuffing. For sure, the posted sim XO'd to a sub wouldn't sound good in my acoustically larger than average room.

With a sub covering up to at least 60 Hz, its overlapping BW will help with the power handling and probably allow another 10 W or more to reach the 1 mm limit.

Dunno, you don't ever post any useful design data, but short of stuffing the @#$% out of it, I don't see how this driver can be flat enough in any high tuned cab, especially a BVR, which IMNSHO is a waste of time/materials for this app.

GM
i abandon them as the design etc are deemed fairly useless so i don't see much point in flogging a dead horse. just start fresh and try again.

what data do i need to post for my posts to be more useful? i've only been looking at doing this for a few months, i need some pointers on how to do stuff around here. its enough of a struggle just to keep up with all the abbreviations.

i'll have a go tuning it lower as per your advice and see what happens.

Last edited by gafhenderson; 22nd April 2012 at 04:16 AM.
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Old 22nd April 2012, 08:05 AM   #15
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not quite the 35hz you wanted.

does this look better?

Click the image to open in full size.

Last edited by gafhenderson; 22nd April 2012 at 08:33 AM.
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Old 22nd April 2012, 07:40 PM   #16
kctess5 is offline kctess5  United States
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Is the geometry on that sim pretty much the same as the previous one only with a lower tuning or is it different? If so would you mind posting it? That looks like a pretty good response for a full ranger, down to 30ish hz you could probably even get away without a sub for music. What driver is this? I saw the t/s specs I'm just wondering the model. I'm wondering how the excursion would do down that low...
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Old 22nd April 2012, 07:46 PM   #17
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Is the geometry on that sim pretty much the same as the previous one only with a lower tuning or is it different? If so would you mind posting it? That looks like a pretty good response for a full ranger, down to 30ish hz you could probably even get away without a sub for music. What driver is this? I saw the t/s specs I'm just wondering the model. I'm wondering how the excursion would do down that low...
no, its a very large internal volume increase and the horny bit is different, its also not the curved shape at present. i am awaiting GM's guidance to see if its worth tweaking further around that design etc.

fane sovereign 12-200lt.

it gets fairly low without exceeding the 1mm of excursion with 1watt, i'll post up the excursion figures later when i boot back into linux.

to be perfectly honest, i'm not expecting much from this driver or the cabinet, its purely to test and learn a few things that i'd be looking to employ at a later date on more exotic drivers, mainly cone size and enclosures and the EnABL process.
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Old 22nd April 2012, 09:16 PM   #18
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there's the displacement for that driver @ 1watt.

lost quite a lot of SPL for the 1mm max budget but the previous design wouldn't be great according to GM knowledge, so i'm hoping it can be tweaked to with some tricks to get the SPL back up.

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Old 22nd April 2012, 10:43 PM   #19
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ok here's the consolidated design, its 'casually' stuffed in the reflex chamber bit only. any good now y'all?

thanks for your continued help

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Old 23rd April 2012, 06:37 AM   #20
kctess5 is offline kctess5  United States
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I like this design, it has nice low end response, and i like how it looks. I wonder how it would model with some more broad range drivers (higher response), I can look for some similar drivers in terms or t/s specs but do you happen to have any others that might do well in mind?
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