Compound loading 6th order quarterwave "Super Planar" horns and pipes concepts/builds

I would like to see some real-world measurements, too. Nothing fancy, just comparison between ROAR and some other comparable PA sub, measured outdoor at high level - preferably at 5-10 meters distance (and scaled to sensitivity @2.83V/1m), with REW or ARTA. No AES papers, no KLIPPEL, just simple down-to-earth DIY measurements. Please?

Exactly. No JBL white-papers needed. Just simple measurements, that's all.
 
I remember to read ROAR thread and the design received many criticisms, the main one I remember was linked to the big dip close to upper band, a simple measurements may answer two questions:

1) The simulation can't represent what was build (bad accurancy) so the frequency responde in the real world is different.
2) If the real frequency response is good as claimed a reverse enginnering needs to be done in order to proper align the design with the simulation.
 
I think they might despise me if i asked them to memorize a line like the one we see in the video from 1:23 to 2:11 :Ohno::tongue:


I think this is a good example of how people had extra time on their hands back in 1929 ;).

Is it inappropriate to make jokes about the Great Depression? :eek: :no: :nownow:


Too soon? :innocent:


Great old recording Freddi, thank you for that :):up:



Let us observe a moment of silence for those poor unfortunate souls who have their birthday on the 29th of February ..
 
Wow, I have never thought about that. How does that work...do they get to celebrate on the 28th, 1st, or both????


BP1Fan ,

Yes, they are the Birthday Challenged, and these birthday deficient people are called "Leapers" and they are rare, the probability of being born a "Leaper" is about 1 in 1461 .... ...

If the condition is not diagnosed and treated early on it then becomes more difficult to cure ... It is contagious, so in the past people who were afflicted with the disease were quarantined in communities known as "Leaper Colonies" ....








;)
 
For my latest project I'm after two high power single 18 or 21 subs with the following requirements:
-Strong till 40 Hz, even 35 Hz is preferred
-Response till 90/100 Hz
-High output from single driver (which eliminates BR)
-External volume about the same (or a tad bigger) as the TH-18/TH-118
-Used with the powersoft 3004PFC4 amp module (so 3kW for one 8 Ohm driver)

I already build a TH-18 2 years ago with the 18SW115-8 and I know how it performs. But since that design was published technology didn't stand still, and other options are available. But the main problem is that I don't have any experience with them. Ofcourse building them would solve that problem, but unfortunately I don't have the time for that, so now I'm here for some advice.

Current list:
-TH-18
-ROAR 18
-Super planar

All would be loaded with the best driver available, except Ipal beacuse I don't have a amplifier available that could drive it. How do these three compare to each other?
 
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@ Mathew - I hope it's ok with you that Impost this, it is somewhat related :)

Johannes dropped by some time ago to have a listen to the ROAR15's, fortunate for me he also brought along a laptop with REW and a Umic.

These measurements where take a in room, so don't stare yourself blind at the results, however, if there where to be something seriously wrong with the design I believe it would have showed up, this is the best I have to show for the ROAR15 for now, but I understand and agree with your wants/needs for proper measurements, that goes for me as well, I'm curious how they would measure my self, especially since I really like how they sound.

I also attended a DIY fair/exhibition just outside of Gothenburg with attendance from all over the country, where I ran the two ROAR15 together with my line sources and received a lot of praise for the system, and in particular the ROAR15, which was very rewarding.

Appreture ROAR15 w. B&C 15SW115 (brand new driver, not broken in):
MynningROAR15-2.jpg


Distortion ROAR15 (same conditions as above):
DISTROAR15.jpg




Remember, these are mouth measurements indoors, I have some difficulties getting outside measurements since I live in an apartment in a tightly packed residential area, but this may change in the near future.
 
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The ROAR definately looks interesting! One criteria I forgot to type in the first post is; It has to be moved around, so some handles would be preffered. Also there has to be some room for the powersoft module, both the ROAR and some super planar horns are tricky with that.

For now the TH-18 still is the easiest cab which checks (alsmost) all the boxes.
-Handles pretty good with the wheels beneath and handles in the corner
-Extensions is good enough
-Room for the Powersoft module

The build is planned for coming June/July, so I still have some time to avaluate all options.
 
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Hello Matthew

As I always say (and it applies with great significance in your case) - thank you for sharing your work! and for pushing the boundaries of alternative approaches, it is a joy and to follow your progress and findings.

Now to the point, the C2A intrigues me, a lot, it seems to be an amazing design! could you please elaborate a bit on them, and please tell me you have a 15" version the works :) if possible (and if you go by my model of publishing your designs free to build) do you have some detailed drawings up somewhere? I would like to know more about them, great work, please keep it up!

...now stop reading this and cracking on that 15" C2A design ;)
 
Martinsson, I have build the TC2E-115, its an alternative of the TC2A-118. Usable from 40hz to 130hz (ish). Great cone control and clean bass.

Type-C2e-master-mk1.png

Type-C2E-115-build-01.jpg

Type-C2E-115-build-02.jpg

Hr-input.png

Type-C2E-115-measurment.jpg

As you can see you need some bracing in the front resonance chamber, to dampen panel resonances, we discovered with other prototypes waterfall plots it keeps the upper tones in check.
 
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THAT is impressive empirical work - to say the least. Is there a pecking order from best to worst? - or do the deflector/plugs work more "specifically" ?

(I wish I had the health and means to do that with the Karlson box) - with the Karlson, a stub absorber chamber
can be used as in the transflex thread with the "Karlflex" - here's MMJ's kluge model as applied to a Sigma 18-2

https://i.imgur.com/z6gyngs.png
 
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Freddi, we found that for this pl215 design a phase-plug that covers 3/4 of the cone from the sides to center, gives to most upper response on the 15" drivers. Not seen on the image the back of the plugs are also filled to about 7mm from cone dust cap. it gave to most flat(ish) response up to about 900hz.

With the 15" drivers I had for test, which was more a bass driver than a midbass driver, the test where not ideal, a good 15" midbass driver with a light strong cone and 'hot' upper frequency response, it might be a very potent large mid cabinet or large a Line array type of build.
Note the pl215 is a large cabinet.

pltop215-phaseplugs.jpg

The Horn used is a 2" 60x90 degr. set to 800hz > 14khz with a P audio BM-D750 CD.

After prototyping the pl215 I build a smaller pl212 KB variant. Which we personally liked more, obvious not as low reaching in hz as the pl215, other reason being more manageable size wise and less wood economically. Has the same very loud output although but faster response and probably easier to get up to 1khz with the right phase plugs. The pl212 Doing 80 <> 450 Hz with ease. We tested both prototypes head to head. And found the 212 sounded better. But as said before with the right 15" it may have been different.

We loaded the PL212 with B&C 12NDL76's. One cabinet can keep up and even surpassing output of 4 Xoc th's at war volume.
 
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So I started with the testcabinet:
An externally hosted image should be here but it was not working when we last tested it.

Probably a bit light on bracing, but I'll see how it performs. Also the diagonal pieces will be added in the mouth.

Powersoft module:
An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.


If they pass the test, I'll build two out of ply, and add wheels and some small handles.