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Thoughts on SI HT-18 x 2

4817 Views 14 Replies 6 Participants Last post by  muzz
Looking at snagging 2 HT-18's before they go away but have some questions.

From what I've seen these model good in larger boxes. What I'm looking at in WinISD as the best option is a 6 cubic foot box. I cant really go bigger than that with the space I have. Does anyone know of a flatpack for one of that size? I see the 4 cubic foot flatpacks at DIYSoundGroup and Parts Express but I dont see anything bigger. If 4 cubic feet is fine then I would just buy one of those as they are quite cheap for as high quality as they are. I'm likely finishing one as an endtable with some Dark walnut on it of sorts, the other would likely be just black with no special finish. Both downfiring with maybe 4" legs and then spikes on them.

My goal is to drive them both with a Crown XLS 1500 in stereo or if needed the 2500. I'm hoping to get away with wiring for 4 ohms so the amp has a decently light load, but open to thoughts......

In general I'm wanting to go sealed to replace my ported DIYSoundGroup Cube 15 so I get more output down low, and with duals spaced right a better response.

My Cube 15 is already more than I need so this is mainly to hit some deeper subsonic stuff and get a decently even response.

Thoughts welcomed.

I should mention the XLS is really being chosen for the lack of fan noise. I will be using XT32 to dial them in and then if needed buying a MiniDSP to tweak further, but a iNuke isnt really something I want to entertain.
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Looking at snagging 2 HT-18's before they go away but have some questions.

From what I've seen these model good in larger boxes. What I'm looking at in WinISD as the best option is a 6 cubic foot box. I cant really go bigger than that with the space I have. Does anyone know of a flatpack for one of that size? I see the 4 cubic foot flatpacks at DIYSoundGroup and Parts Express but I dont see anything bigger. If 4 cubic feet is fine then I would just buy one of those as they are quite cheap for as high quality as they are.
I believe that 4ft^3 enclosure from the DIYSoundGroup is designed for the HT-18, so if that's the case it should work fine. You could increase the perceived volume by adding 1lb of loose-fill stuffing per cubic foot, which probably isn't a bad idea anyway (reduces the backwave off the driver).
I believe that 4ft^3 enclosure from the DIYSoundGroup is designed for the HT-18, so if that's the case it should work fine.
Yeah the DIYSoundGroup 4 cubic foot box does have a option for a cutout for a 18" Stereo Integrity driver.

You could increase the perceived volume by adding 1lb of loose-fill stuffing per cubic foot, which probably isn't a bad idea anyway (reduces the backwave off the driver).
Gotcha. I wasnt sure if adding polyfill would do that, but I was planning on adding a bunch of polyfil on all the sides regardless. If thats the case then 2 of the 4 cubic foot boxes would work great. They are smaller than what I have now (wife will like that) and will make it easier to build one into an endtable as I will just wrap it with decent wood on all sides, make legs and a top and be good....

Do I want to use foam as well or JUST polyfil?




Any thoughts on if I should wire for 2 ohms instead of 4? These drivers dont really need a TON of wattage to sound good, but I know with sealed you need MORE power than Ported, and dont have to worry as much about overdriving them with too much power....
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Just polyfill. Packed densely but evenly (not jammed in and condensed - it needs to 'breath', as it were).
I wasnt sure if adding polyfill would do that.......

Any thoughts on if I should wire for 2 ohms instead of 4?
Some old test results: https://web.archive.org/web/20120620065121/http://www.nousaine.com/pdfs/Box Stuffing.pdf

Well, the higher the resistance, the lower the current draw, required wire size, amp loading, which most are voltages sources first and current sources second, i.e. can't make 2x power with every halving of resistance, so for a given SPL, it takes more and/or longer for thermal power compression [harmonic distortion] to alter the frequency response. This is sufficient reason for me to use 8-16 ohm systems depending on the amp, but a 2 vs 4 ohm search should yield more pros/cons.

GM
Looking at snagging 2 HT-18's before they go away...
I haven't been on that much lately, but someone please tell me this is just a change in models or something, and that SI isn't closing its doors or something else terrible. Discontinuing a model line to bring out something new I can bear, but I hate the thought of these subs going away for good like so many other great drivers have.
From what I understand Nick is getting out of the consumer end of things and focusing instead on OEM. I believe he's struggling with some health issues though, so there may be more to it than that.
I haven't been on that much lately, but someone please tell me this is just a change in models or something, and that SI isn't closing its doors or something else terrible. Discontinuing a model line to bring out something new I can bear, but I hate the thought of these subs going away for good like so many other great drivers have.
The HT line is dead, but another low priced 18" driver is coming out from them. It will be priced below the HST driver but higher than the HT-18.

Details here.

Meanwhile I'm likely looking at HST-18's so I don't ever feel like I need more from my drivers....
Was "details here" supposed to be a link?
Was "details here" supposed to be a link?
Yes lol..

Here is the link

http://www.avsforum.com/forum/index.php#/forumsite/3207/topics/2202337?page=1
Thanks Bean (Ender's Shadow?). That wasn't what I was hoping to hear, but it wasn't the worst news in the world, as long as Nick's health improves. We are finally getting close to starting our basement and I was pretty set on a pair of sealed HT18's.

That link just took me to the main AVS page, but I'm guessing it was supposed to go to a page about the new DS4-18 driver. Seems like it will be an improvement, with a cost increase. I'd rather see that than a total market exit. Hope it works out well and sticks around long enough for me to take advantage.
Thanks Bean (Ender's Shadow?). That wasn't what I was hoping to hear, but it wasn't the worst news in the world, as long as Nick's health improves. We are finally getting close to starting our basement and I was pretty set on a pair of sealed HT18's.

That link just took me to the main AVS page, but I'm guessing it was supposed to go to a page about the new DS4-18 driver. Seems like it will be an improvement, with a cost increase. I'd rather see that than a total market exit. Hope it works out well and sticks around long enough for me to take advantage.
Yes the thread got deleted. But you found the driver name and the specs are back on AVS at least for now.

I'm sure if you posted a wanted ad at AVS you might find some.

Also worth mentioning is the Dayton UM-18 which is pricey BUT if you but it AND a flatpack from Parts Express they take 50% off the enclosure which makes it cheaper.
In my case I'm back to looking at 2 X HST-15 with dual Dayton SA-1000 amps so I don't have to worry about a highpass that the Crown XLS have nor any voltage issues since it takes RCA in and doesn't need 2VRMs to be fully powered..

That said its a very pricey proposition as I'm looking at at least 450 a driver + 90 for each sealed 3 cubic foot flatpack AND then another 350 one time for the amp.

All said and done that puts me over a grand close to 1200 bucks but it will be the last sub system I should need...
Just in case anyone wanted a link to the active thread for the new DS4-18 driver from SI
The 1st batch of DS4-18 just got delivered today, and is available for order through Sundown.

Sent from my XT1575 using Tapatalk
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