Stereo Integrity's new HT Subwoofer - Page 49

Also, I know I need to do an L-T, so suggestions on doing that with the DCX are welcome. The subs are crossed to the mains at 60hz, but I am not positive I'm done playing with that yet.

Very cool!!

Do you have pictures posted anywhere yet? What is your room size?

I can't imagine what having 8 of these would be like. With two anything below 20 hz activates everything in my kitchen (right behind the MLP). The pot rack hanging above the counter goes nuts.

Finally got the granite tops for these finished.

Granite looks nice Ben!

That is awesome. Top notch work.

Ha. I love the meme face.

Do you plan on adding any finish to them? Or just leave the wood natural?

AFAIK, true LT is not supported by DCX. I was told however that in practical terms shelving filters are just as good. I have +6db L12 set at 35Hz on my inuke DSP driving CHT SS18.2 box

There were two faces. One is less obvious.

I had originally planned to stain the wood. But after many samples, I was never happy with the result. I'm sort of leaving it up in the air for now. I didn't roundover the edges, leaving my options open. It's sort "good enough" for now. My wife is due for our second son TODAY, so I'm going to postpone any new projects for a while.

I have wanted to give some of the more costly laminates a try, a'la Chemetal, Interior Arts, and Treefrog. I could do the 4 exposed sides for both from a single 4x8 sheet.

I use the Low shelf on my DCX as well, I have a 3 dBs gain, 12db/octave slope, starting at 20hz. This means I don't need much boost down low. When you start it at a higher frequency you will get more boost down low, more like a house curve. I wanted just to level out 5-10hz with my 20hz. It does make the teens a little hot if you are already flat there. This is the wheel house of many movies and gives it a little extra, truely fun!

Some front stage pics in this thread, and room is 11x29x8 so not super tiny, but not huge I should get some final pics once everything is completely done.


exactly, that was pretty much where I was headed. 6-8dB at 35-40hz L12 shelf and then have an additional range based filter to pull anything upwards of 20 back down to flat... I also need to get my gain structure thing going as well

Is that Birch ply? If so, was it just not taking the stain well, perhaps getting blotchy? I was having issues with birch and found a simple solution.

Laminates do look great as finishes.

Good luck!

Keep in mind that Stereo Integerty is closely intertwined with Sundown Audio and Obsidian Audio. If I understand correctly, these HT subs are a joint venture of the sorts. I forget if SI the comany is a JV or just these HT subs. Do you recall beast?

Regardless, both are established brands in the Car Audio scene. Anything is possible I suppose, but maybe knowing this product is leveraged between a few different stake holders may give you piece of mind? Oh, and the fact that they basically sold their entire stock of 18D2's shortly after they started shipping...



As beast stated, they weren't prepared for such a positive response from the HT community... I'd say with confidence that they've made moves to ensure they don't run into this issue in the future. *Cough*40ft connex


Me no likey...

Would like it to read..."the whole system from 4hz up..."

Is that ridiculous of me?

Not saying that you haven't encountered bass Nirvana, just makes it sound like your XXX's may have been a bit more fun in the infrasonic range...

It depends on room and electronics to get there. Most processors start rolling off at 5hz anyways so you are fighting that. BTW, just because your mic, soundcard, etc... rolloff does not mean people are not flat to whatever, it just means we can't measure the true low end. Now if processors, DCX's, amps, etc. rolloff early then that makes it very hard top get to 3-4hz.

Well he did just get done saying that his response falls in his room below 10hz so of course that is what he'd say.

Beast, get the DCX in line and add the shelving filter.

People, a real Linkwitz Transform isn't really needed for us as we want low end boost only. An LT also changes the end Qtc of the subwoofer system and for HT we really don't care about that.

No. It was an "oak" veneered ply from Menards. Decent enough quality plywood, but not so great veneer. Paper thin.

If you look closely, they even source some sundown parts on the HT's Their MKIII is actually part of SI as well but is not in production right now. I think Nick is plenty busy right now.


Well assuming I have had the EXACT same drop-off, at the exact same spot, and others have seen it using omnimic as well, I think the system is the last thing I need to check. I mean, my room gain, I am DEAD flat to about 11-12hz and then it drops hard. I have stated this before, but it is either my BD player (Denon 1611UD) or my cables (Not a chance) since others have measured down into the single digits with the exact same setup. Other considerations is a leaky room, or need to send my mic off to Dayton to be calibrated With that said, I am also still in a concrete bunker, and my woofers are still moving at 4-5hz so, take that for what its worth

You need solid silver cables to get response below 10hz. Everybody knows that.

I keep forgetting that your measurements always had the same drop off. It could very well be your measurement system. Are you using Omnimic? Which version? I have the gen1 but mine was supposedly calibrated to work to 5hz. I also show a drop just under 10hz with my measurements but that's with an 11hz tuned LLT system sooo.... you know... that makes perfect sense. With your sealed XXX's and SI's... that shouldn't be.

Do you have another microphone to test and maybe test it with REW? Could show a pattern of such.

I'd check your Omnimic, make sure it's calibrated with the included code that came with it, check for software updates. Any nearby buddies with a calibrated REW system?

Correct Scott,
When you see a ported drop on a sealed system it is usually when the electronics and or mics system fall off because the sealed system will gradually rolloff. It happens to me all the time and it will be dead flat and then just drop! I know that is not an actual in room response down low but with everything rolling off together it creates a huge drop off. Just add a -3 dB point from all the gear(minus clone) at 5hz and you will get what? I would think anywhere near -15 dBs or more accounting for measuring mic, soundcard, DCX, processor, bluray player, etc.... Now if you want to get flat to 3hz just add the boost needed but make sure you have the displacement and power to overcome those roll offs. I want to know why a processor would rolloff at 5hz if the spec calls for 3-120hz. Is it -6 dBs at 3 hz and a processor rolls off -3 dB at 5hz so it meets specs? Anyone in the know?

Hey Scott, I used to have solid silver cables at one time, we all have to learn at some point. I do think processors matter at reference though. Not in the details though.

No close REW or OM friends anywhere close. unfortunately. I am just going to get the system as good as I can and then send the mic back to have it calibrated, as I am using v1.0 of the OM and even though I have the update, and my mic has a code on it, I don't think it is the right one to just plug in the correction file. Back a while ago when Dayton was offering to take them back and have them calibrated, I was too busy using it so I never sent it off. Looks like that is exactly what needs to happen at this point though

That is a correct assessment -- Nick and I are working together on the SI HT project; we are confident in the time-line on the 2nd production run +/- any usual variances in customs clearance (usually a week or so variation).

The response was certainly much higher than expected, especially on 18s -- with some actual demand data on-hand it will be easier to keep them in stock in the future; at least by the 3rd production cycle (data is choppy due to the rapid sell-out). We had essentially no data on sales until the time at which they arrived; at which point they all left our facility almost immediately leaving no time to react on production.

The SI HT line is here to stay -- it is not a fly-by-night or a basement operation by any means Thanks for the comments. Nick is primarily the face of SI in both car audio and HT terms but he and I do alot of work together behind the scenes and the SI HT project is very much so a cooperation between us; car audio under SI is primarily Nick.

Ha, yeah you didn't count on guys like me that had always been afraid to go DIY to jump on board (and buying 8 of them!!!). A driver that measures this well and by all accounts sounds fantastic at this price... I'm sure I wasn't alone in going DIY. I always had it in my head that you had to spend a minumum of 400-500 dollars to get a good 18" driver, thanks for killing that notion.

I know when I measured using a v2 OM (with the 4.0 software) my system also took a digger at 10hz. I measured a couple of other systems and they also had similar drop-off's. Personally i question the accuracy of the mic with the under 10hz stuff.

Or perhaps it might have just been that paticular mic i used?? HHHmmmmmm.....

I remember your nasty 10hz cliff...lol

It's that damn mic I'm telling ya!

We all thought we were set for life with our Caps and Submersives.... but nooooooo. These come along and measure so well and at such a great price, most of us jump into DIY to build multiples of these monsters.

Then we all caught full on DIY sickness, and it looks like we're here to stay... unless some other uber speaker/sub pops up, which we will then make DIY versions of anyway.

Its never ending, but so worth it.

Popa and Beast - You guys have issues. I thought I was a bass head until I was shown Popalock's plans for his HT room. (On a side note, if you guys ever want to experience 150 dB broad-band just stop by the shop and I'll sit you inside the Obsidian Audio CRX with two of our Obsidian Audio 18" subs powered by 3,000 watts, haha - it meters at a 149.9 legal from 20 Hz to 90 Hz).


I think we've proved ourselves. Period. No "vaporware."

The only part that we sourced from Sundown was the spacer ring. It boiled down to tooling our own spacer ring with (or without) or log on it that was the exact same dimension as the Sundown spacer ring and adding another $15 to each woofer OR simply using an existing spacer ring from a close friend with no additional cost to you (the customer). We opted to keep things less expensive for you guys. The spacer ring, cone body, and rubber gasket, are the only items the two companies share.

On a quick side-note (only because it was mentioned in the above quote) the BM mkIII/mkIV suboofer was/is a huge hit. They sell for more used than they sold for new. Totally unique, totally not-what-you-think-the-public-wants product. But they ended up selling faster than we could get them in stock. We are now working on an improved mkIV version with a plethora of upgrades.

As Jake has pointed out above the HT line is here to stay. We are very proud of every aspect of the design and the performance. It is not going anywhere.

Yup. You have no idea how hard it was for me to pay more for used ones floating around DIYMA than they sold new for. After a listen however, the pain quickly abated.

I just scooped a calibrated UMM-6 so hopefully I will be able to shed some light on this deal here. They said they usually ship within 5-7 business days so hopefully sometime next week I will be able to measure something a little different than what my current rig is showing


Nick, Not crazy! How could you be crazy when what you do gets a response like this?

Double