Elemental Designs A7-450

[mike c]

http://edesignaudio.com/edv2/19ov2_video.php

 

[majorloser]

You gonna try that with the DD-18?

 

[mike c]

no!

i was thinking something less insane:
http://www.edesignaudio.com/edv2/product_info.php?products_id=606

 

[majorloser]

There goes that Philippine Plate again!

I don't think that hemisphere can handle much more vibration.

 

[paulf7509]

crazy!!!

 

[agarwalro]

There goes that Philippine Plate again!

I don't think that hemisphere can handle much more vibration.

ROTL. Nice.

 

[Tomorrow]

Well? Did you do it?

 

[mike c]

im asking eD to quote me a single driver version of that sub so I can buy duals. still no go ... they said, to tune a single driver low ... the box would have to be just about as big as the 900.

if the two boxes would be too expensive ... i'll figure something out.

 

[GlocksRock]

You could always just buy their drivers and build the boxes yourself.

 

[mike c]

You could always just buy their drivers and build the boxes yourself.

sealed will be easy ... vented will be totally over my head.

 

[GlocksRock]

Plenty of people over at the ICIX forums can assist you in getting box plans with the proper tuning frequency, the box will be a little more invloved, but shouldn't be too difficult to build. But yeah, I personally wouldn't attempt to make my own ported box, I don't have the woodworking skills.

 

[jonnythan]

sealed will be easy ... vented will be totally over my head.

The only difference between building sealed and vented is that a vented box requires you to cut a round hole for a $10 plastic port.

That's all.

If you can build a sealed box, you can build a ported box.

 

[annunaki]

The only difference between building sealed and vented is that a vented box requires you to cut a round hole for a $10 plastic port.

That's all.

If you can build a sealed box, you can build a ported box.

Building the enclosure is close to the same, but designing it is totally different.

 

[jonnythan]

Building the enclosure is close to the same, but designing it is totally different.

Indeed. Not really any tougher, though, if you use a modeling program like WinISD.

 

[mike c]

but for the tuning freqs. we AH need ... we're gonna need very big and long port areas and length ... something maybe slot ports will give (that I don't want to compute for)

 

[jonnythan]

What kinda frequency are you trying to tune for? Shouldn't be that hard. I've got a box tuned to around 20 Hz with a port about a foot or so long.

 

[mike c]

that's what's stopping me. you see, I see these HSU, SVS subs tuned up to 10hz with a single port and a small box (relatively speaking)

but eD tells me that I need a 10 cube box for an 18hz tuning (i wanted 15hz btw, but they tell me it's gonna be bigger) they say that if you have a small port and a low tuning, you'd hear a lot of port chuffing.

note: they did say the 10 cube box would model at 116db at 18hz, 112db at 15hz ... whatever that means

ok ... how come they don't ask me the room size or how loud you're gonna play it? it's like they have a "minimum requirement" thingy they follow.

 

[annunaki]

Even when using a program such as WinIsd there is more that goes into it that meets the eye. You have to check the air speed from your port design to ensure that you are not going to have noise. Check the impedance to ensure it will not be to difficult for the amplifier to handle. Check the excursion to ensure the driver is not over driven for a given enclosure. Check the attack and decay (can't think of what the actual term is in WinIsd) to make sure there is no audible overhang. For the average person they do not know what the numbers mean or the thresholds to look for. Ported can be a tougher task for those that are not quite sure how to use a program to its fullest.

 

[jonnythan]

If you're not willing to look at excursion, group delay, etc, you shouldn't be building your own sub, IMO - sealed or ported.

 

[annunaki]

I agree. However many of the people asking about DIY on the forums do not understand these principles thus the hesitation in doing so. As you can see, it is not as simple as you suggest for "the average" person.