So I was modelling some boxes for (4) RE Audio REx 10's for my '14 Kia Soul. I only have about 4 cubes to work it, both boxes tuned to 37hz.
I will have 1000rms being fed among all four.
These are the boxes that I modelled:
Assuming no losses:
In the green is simply a ported box, 6.7 db peak 50hz, f3 31hz, f10 24hz
In the orange is IsoBarik, I get 11 db peak 39 hz, f3 28 hz, f10, f10 23hz
I'm not familiar with IsoBarik--Would loading them in a push/pull configuration really give me a theoretical 6db gain at a lower frequency? I'm not a fan of 50hz bass (30s are my favorite.) I'm assuming I'd have less cone area in a push/pull configuration, though, resulting in about an equal gains...can someone provide insight on this?
I'm really limited by space and alternator power with this build otherwise I'd go way bigger.
You guys are the best!
I will have 1000rms being fed among all four.
These are the boxes that I modelled:
An externally hosted image should be here but it was not working when we last tested it.
Assuming no losses:
In the green is simply a ported box, 6.7 db peak 50hz, f3 31hz, f10 24hz
In the orange is IsoBarik, I get 11 db peak 39 hz, f3 28 hz, f10, f10 23hz
I'm not familiar with IsoBarik--Would loading them in a push/pull configuration really give me a theoretical 6db gain at a lower frequency? I'm not a fan of 50hz bass (30s are my favorite.) I'm assuming I'd have less cone area in a push/pull configuration, though, resulting in about an equal gains...can someone provide insight on this?
I'm really limited by space and alternator power with this build otherwise I'd go way bigger.
You guys are the best!
Okay, fair enough.
The isobaric is using twice the number of drivers (and presumably twice the power - the old WinISD isn't too good for that) to get 6dB gain at one frequency. If you double the size of the normal ported box and add a 2nd driver, you'll get 6dB gain right across the band. Way more output.
Only use isobaric if you want things to be as small as possible, accepting that you'll need to throw power and extra drivers around.
Chris
The isobaric is using twice the number of drivers (and presumably twice the power - the old WinISD isn't too good for that) to get 6dB gain at one frequency. If you double the size of the normal ported box and add a 2nd driver, you'll get 6dB gain right across the band. Way more output.
Only use isobaric if you want things to be as small as possible, accepting that you'll need to throw power and extra drivers around.
Chris
I'm using WinISD Pro (I'm under the impression when you say the old one, you mean non-pro?)
I've accounted for "2-pairs" when setting it to IsoBarik. I mean if it's literally mounting the subs in a push pull, wiring internal sides opposite polarity, I think I can wing it with cutting two holes and mounting them before I put the last panel on. If I don't like it, I'll simply cut two more holes so I can access the internal subs again.
Image for the lulz:
Like I said, I can't double box or power, I'm limited to a 110-amp alternator (12volt) and 4 cubes. I know most people on here aren't car-audio guys but i'd consider this forum way more knowledgeable in acoustics than diyma/diymobileaudio.
I've accounted for "2-pairs" when setting it to IsoBarik. I mean if it's literally mounting the subs in a push pull, wiring internal sides opposite polarity, I think I can wing it with cutting two holes and mounting them before I put the last panel on. If I don't like it, I'll simply cut two more holes so I can access the internal subs again.
Image for the lulz:
An externally hosted image should be here but it was not working when we last tested it.
Like I said, I can't double box or power, I'm limited to a 110-amp alternator (12volt) and 4 cubes. I know most people on here aren't car-audio guys but i'd consider this forum way more knowledgeable in acoustics than diyma/diymobileaudio.
After reading a few articles that didn't give a concise answer regarding efficiency, this one seems to explain it well:
Audio Innovation - by Dan Marx www.danmarx.org
An excerpt:
...When you compare isobarics to a system which houses two drivers each in their own enclosure, this system was actually 6 dB less efficient.
So I suppose that's my answer. Maybe one day I'll play with it for ***** and giggles.
Audio Innovation - by Dan Marx www.danmarx.org
An excerpt:
...When you compare isobarics to a system which houses two drivers each in their own enclosure, this system was actually 6 dB less efficient.
So I suppose that's my answer. Maybe one day I'll play with it for ***** and giggles.
I think it's clicking with you now. You actually posted the page I have bookmarked for myself to recall the theory differences. Personally, I still dig the look of the iso cabs. A plexiglass top or side so you could view the clamshells would be killer. While you might not achieve your intended goal the sound quality is still there too.
Hi,
Well I wouldn't call loud one note 50Hz bass with no depth much fun at all.
The fast vented roll-off below 50Hz does not utilise the cabin gain well.
Here 1 cuft per driver sealed and stuffed is ideal to utilise the cabin
gain for very deep bass, which will be far more even and tuneful. *
Volume wise with 4 x 10" 12mm excursion drivers and 1000W
on tap, in the volume of a car should be more than plenty.
rgds, sreten.
* As a further point sealed will mean you can hammer the drivers
as hard as you like with a common overload point in the low bass,
you can't do that with vented, it needs high pass protection.
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Opinion.
I've built many sealed setups (why not, it's less work?) and have never been satisfied.
Most music with real instruments barely goes below 40 hz, yet alone 20 hz so I don't know why -you- would need "low extension" anyways. Maybe for home theater applications.
Have you ever heard 25 hz @ 145-150+db?
In a vehicle with thin sheet metal, even with layers upon layers of deadening and foam, it's hard to contain, causing resonances and basically fighting the woofers. Fast bass comes from good midbass-speakers, which I would disable subs if I truly wanted "accuracy." Not that I'd call the interior of any vehicle accurate.
Oh, also, I think you're forgetting about this thing EQ... You should read about it!
There is no such thing as fast bass and you can't effectively EQ a ported box below tuning.
This little writeup might be helpful for ideas on how to tune with cabin gain in mind.
http://www.diysubwoofers.org/projects/car/sub3/
This little writeup might be helpful for ideas on how to tune with cabin gain in mind.
http://www.diysubwoofers.org/projects/car/sub3/
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Hi,
I agree most real instrument music doesn't get below 40Hz except
for the kick drum, but there are music genres that very much do.
No I've not heard silly levels of 25Hz in a vehicle or a room.
(I did set up a friends car system that seemed to have almost
bottomless bass with a sealed sub, when its not moving.)
I'm well aware of EQ options. You didn't make it explicit that
your after a max SPL alignment that would then be EQ'd.
Vented highish is a better option for that scenario.
rgds, sreten.
I agree most real instrument music doesn't get below 40Hz except
for the kick drum, but there are music genres that very much do.
No I've not heard silly levels of 25Hz in a vehicle or a room.
(I did set up a friends car system that seemed to have almost
bottomless bass with a sealed sub, when its not moving.)
I'm well aware of EQ options. You didn't make it explicit that
your after a max SPL alignment that would then be EQ'd.
Vented highish is a better option for that scenario.
rgds, sreten.
When I say EQ, I mean cut @ 50hz. I never add with EQ.
Why do we look at impulse graphs then?
I'll definitely check out cabin gains, obviously aware of them but not how to manipulate them to one's advantage.
It must not have been very loud. Loud being relative. Like I said, I prefer huge, body-numbing bass that shakes your vision. Sorry you don't, to each their own. If I'm at home, relaxing, sure, I'll kick on some Eagles at low volume.sreten said:
One of the better "live" sounding systems was Earl Gedes' Abbey. My girlfriend thought they were very harsh and bright, I thought they were too mid-bassy, although accurate to a live concert.
One of the best overall speakers I've heard are Jim Salk's Soundscape 8.
B&W CM9's sound amazing for classical.
And finally, I'd prefer MartinLogan ESL's in my theater for movies. It just depends on the situation. I don't think there's a perfect overall setup that does everything perfect.
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