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18" reflex sub ports
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toastyghost View Drop Down
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Points: 10919 		Post Options Post Options   Thanks (0) Thanks(0)   Quote toastyghost Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 2:50pm
Probably best if you drop us an email for prices but here's a video of one SM80 in direct A-B comparison to a guy's 3x QSC KLA12 which is a cut above the DVA Mini https://www.youtube.com/watch?v=c9ITyQALXPg

Just a note on your kick design though, do bear in mind the phase response of a ported enclosure in comparison to the tapped horn. There's a good chance that you'll struggle to get them to work together well due to vastly different phase responses / group delay even if you're happy with each design by itself.
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Hemisphere View Drop Down
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Points: 2272 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Hemisphere Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 2:57pm
I guess I'm just thinking about aesthetics really. Maybe that's not such a big deal, but if you had a 6 or 8 box system, with the TH18, kick bins and coax tops, you could give it all a coherent aesthetic. Matching paint, grilles, cabinet hardware etc. There's something satisfying about a system that looks as well as sounds coherent.
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stalian87 View Drop Down
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Points: 110 		Post Options Post Options   Thanks (0) Thanks(0)   Quote stalian87 Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 3:00pm
to be honest, i can guarantee it'll be out of my price range lol!

I'm also gonna go the sealed route even if it means a slightly larger cab.

I may be tempted to design a coaxial midtop but i wouldn't know where to start!
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stalian87 View Drop Down
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Points: 110 		Post Options Post Options   Thanks (0) Thanks(0)   Quote stalian87 Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 3:02pm
yep aesthetics are a huge thing for me. I've got the TH18's sprayed in a gorgeous metallic black which sparkles nicely with uplighters and so i'll need the whole rig to eventually look exactly the same.

I'll upload a couple pics of my th18s
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kevinmcdonough View Drop Down
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Points: 3751 		Post Options Post Options   Thanks (0) Thanks(0)   Quote kevinmcdonough Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 3:04pm
hey

For your original design brief of a kick cab, I think you'd be hard pushed to do much better than a high quality 15" driver in a compact box. Playing 60 Hz up excursion wont be a massive problem, so you'll be able to throw quite a lot of power at it and I think 1 would keep up with 1 tapped horn not too bad. While its great to think about having cabs with 4 12" drivers and such, I think you'd be looking at massive complication and a huge heavy cab that would be less than ideal for transporting. 

However if you were looking to change your tops, you could look at Peter Morris' DIY90 from the SoundForums page. 


It has some fairly expensive drivers in it, and needs good quality processing to achieve its best, but everyone who hears it pretty much regards it as one of the best speakers they have ever heard, brand name or otherwise. 

K
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Hemisphere View Drop Down
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Points: 2272 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Hemisphere Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 3:08pm
Originally posted by Stalian87 Stalian87 wrote:

I may be tempted to design a coaxial midtop but i wouldn't know where to start
At it's most basic, it's just a sealed box enclosure. Danley does all the fancy stuff and it will sound better of course, but there are always diminishing returns with design enhancements like that. (it's a relatively big and heavy box for a start, it wouldn't fit your compact requirements)

Here's a BMS coaxial stage wedge, for example:



Edited by Hemisphere - 24 August 2017 at 3:13pm
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stalian87 View Drop Down
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Points: 110 		Post Options Post Options   Thanks (0) Thanks(0)   Quote stalian87 Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 3:11pm
https://drive.google.com/open?id=0B_XE8UpzG2cvemNaRnNDWHlPc28
not the best pic but you can roughly see the shine on it.

yeah you're right, it will be pretty big and heavy but would i get that punch as well as 4 12"s?


Edited by stalian87 - 24 August 2017 at 3:13pm
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stalian87 View Drop Down
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Points: 110 		Post Options Post Options   Thanks (0) Thanks(0)   Quote stalian87 Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 3:12pm
i almost built 2 wedges a few years ago actually with coax drivers so midtops would practically be the same thing.
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Hemisphere View Drop Down
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Points: 2272 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Hemisphere Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 3:31pm
Originally posted by kevinmcdonough kevinmcdonough wrote:

I think you'd be looking at massive complication and a huge heavy cab that would be less than ideal for transporting. 
If it's split into two boxes then each 2x12 half would be smaller than a 15" vented kick bin.

One 2x12 sealed can reach 129-132dB across the required range (with the BMS 12s305), and you won't readily exceed that with a smaller/lighter 15" vented box.

Although that BMS has a slightly heavier cone of 95g Mms, it's high BL of 20.14 means it's similar to other 12" drivers with 65-75Mms

Punchier/faster options, with 50-60g Mms require two double 12's to reach SPL in the 130's, but can still manage 125dB with just one double enclosure, and it sounds like that'll be enough in many cases (if the 126dB dB mini line array is considered a serious option).

It's definitely an extra hassle but surely the bottleneck of weight and mobility in this system will always be the TH18, which is like 415 litres external dimensions. We're talking about something like 100-115 litres external for each kick section with 4x12 sealed. (80 litres internal + wood/hardware + the space in front of the v-baffle, which actually adds a little to the performance which we can't readily calculate in WinISD)

My thinking is that if the kick is powerful enough, with plenty of weight to the sound around 65Hz but not too much SPL that it overpowers the TH18, it could effectively stave off the desire for another pair of TH18's, so the potential for keeping the system portable in the long run would be higher.


Edited by Hemisphere - 24 August 2017 at 3:53pm
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stalian87 View Drop Down
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Points: 110 		Post Options Post Options   Thanks (0) Thanks(0)   Quote stalian87 Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 3:50pm
i agree
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Hemisphere View Drop Down
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Points: 2272 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Hemisphere Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 4:08pm
Sorry, I've got the numbers way off there. It's 125-129 for 2x12 with the BMS, 131-135dB with 4x12

With a more lightweight driver (50-60g Mms, 8-9mm xmax), it's generally around 122-127 for 2x12 or 128-132 with a 4x12. (with half the amp power required of the BMS, but no more headroom available)

That's across the 70-125Hz range with a rising response, 20 litres sealed enclosure per driver. You can get an extra dB gain in the low end of the range with 30 litres per driver.


Edited by Hemisphere - 24 August 2017 at 4:12pm
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stalian87 View Drop Down
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Points: 110 		Post Options Post Options   Thanks (0) Thanks(0)   Quote stalian87 Quote  Post ReplyReply Direct Link To This Post Posted: 24 August 2017 at 4:46pm
I'm gonna go for the 4x12 but looks like I have to make the box higher than wanted cos I can't simply work out how to create the baffles to vertically and horizontally align accurately! Using sketchup and just can't figure out an easy way to do that! If anyone can help that'll be appreciated!
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