Beyond the Ariel

Nice work! The best and most scientific would be to staple a thick felt on the front and on the edges fiber glass insulation, but since science wasn't able to refine simple two way design for last 100 years just do what your wife/GF will find attractive and will allow you to put in the living room. So you can listen together and not alone or with your dog in garage or the cellar.
 
Here's Martin's picture of the AH340. Maybe I can get them painted Burgundy in an automotive finish, to match the Bubinga veneer of the bass cabinets.

This would allow a 500 Hz or lower crossover at a moderate slope, simplifying the task of the 15" driver.

View attachment 1243531

Beyond something?

This will give a strong beaming speaker system going back to the 50s and 60s of the last century:

Siemens Klangfilm etc.
 
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Sounds great to me, I’m not running a theater, I’m sitting in front of my system listening to music 😉 “Beaming” could also be called
“focused”, which means high efficiency and less room interaction. It’s not a negative, just an option. I think wheels have been in use for many millennia and we still seem to think a rolling circle is hard to beat.
 
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Well, even if you're not running a theater a shifting of image from the left to right with a turn of a head may be bothersome to some. Multiway horn rectifies this problem to a degree. CD horns supposedly solve that but the balance is is not as natural as horns without a slot. It may sound great but if you listen to speech through a CD horn and then through an open horn the difference is obvious as demonstrated by Bruce Edgar. Everything is a compromise to a degree and squeezing every drop of bandwidth from a single horn is not an optimal solution. Pick your poison
 
I think I'm going to make this one way beyond Ariel. Picked it up from the curb today. 15" based ...CD horn
 

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OK so I have a question regarding baffle edge diffraction and large radii at the edges. I was able to knock out the cabs for my 15PR400/Rosso65CDN-T/AH425 build, and had planned to put a 38mm radius on the left and right edges, but the way they look with the 36mm of Baltic birch edge showing, I'm smitten and don't want to grind into it. I know Lynn has made a good point for large radii but I'm not ever going to do 3-4" as he did, and from what understand, lower midrange and bass frequencies really aren't that affected enough to even measure let alone hear. This probably explains why so many big drivers are surface mounted as well. What I'd like to do is spray everything satin black but leave the edge grain with a clear finish, make it a feature. Any good science on this from anyone? Thank you, here's a couple of shots:
View attachment 1245079 View attachment 1245080 View attachment 1245081
Is that pre-finished plywood? Looks amazing, simple,clean.
 
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Any good science on this from anyone?
Yeah, consider the driver's pipe end correction on a baffle k = 0.732r ;)

15PR400's Sd = 857 cm^2

radius = ((857*4)/pi) = ~16.52 cm

k = ~16.52 cm*0.732 = ~12.1 cm

driver eff. dia. = (2*16.52)+12.1 = ~45.12 cm/17.77 "

baffle eff. dia. = pipe end correction on a baffle k = 0.732r = ~9.52" + 26" = ~35.52"

baffle frequency = ~13543/2/35.52 = 190.7 Hz, down in the 'boom/punch', 'warmth' BW, so IME a good place to 'hide'/'blend' in a bit of driver/baffle (euphonic?) 'ripple'. ;)
 
Is that pre-finished plywood? Looks amazing, simple,clean.
Just Baltic birch, the exposed edges were trimmed down with a giant bottom bearing trim bit, like you'd use for veneer or laminates, except scary big. Just a quick clean up sand to 120, there will be a lot more fussy sanding then spray with black lacquer, but the edge grain will stay visible with clear finish. Now I"m going to go spend a few hours figuring out what GM just said and learn something :oops:
 
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Yeah, consider the driver's pipe end correction on a baffle k = 0.732r ;)

15PR400's Sd = 857 cm^2

1. radius = ((857*4)/pi) = ~16.52 cm

2. k = ~16.52 cm*0.732 = ~12.1 cm

3. driver eff. dia. = (2*16.52)+12.1 = ~45.12 cm/17.77 "

4. baffle eff. dia. = pipe end correction on a baffle k = 0.732r = ~9.52" + 26" = ~35.52"

5. baffle frequency = ~13543/2/35.52 = 190.7 Hz, down in the 'boom/punch', 'warmth' BW, so IME a good place to 'hide'/'blend' in a bit of driver/baffle (euphonic?) 'ripple'. ;)
OK GM I'm stumped again. This calls for a list, apologies for my density. I added numbers to your lines above, and will use them to call out my questions:

3. So you add the corrected baffle radius to the true baffle diameter?
4. where is the 9.52" coming from?
5. Fine with the math, but I don't catch your Georgia humor, how it relates to whether to add a radius to the baffle edges or not? And my baffle is only 22" wide, so using your formula I get 214.8Hz, still not too bad, I'm hoping the ports will prop up the FR enough to avoid BSC and loss of sensitivity, but there might be a sag in the midbass range, I'll know soon enough when I start measuring 🧐
 
My conclusion is that any audible discontinuities a baffle's sharp corners/whatever might generate will at worst be lost in the speaker's musical output primarily due to its low amplitude and perceived in a part of the human hearing BW where we would have a hard time noticing it unless considerably louder than the surrounding music/noise.
 
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Here's Martin's picture of the AH340. Maybe I can get them painted Burgundy in an automotive finish, to match the Bubinga veneer of the bass cabinets.

This would allow a 500 Hz or lower crossover at a moderate slope, simplifying the task of the 15" driver.
The horns allowing so, not the painting of same. Syntax error? Sorry; can't assume anything in this game.
Maybe add a superweeter or two pointing at the wall behind the speaker.
I recall this being briefly discussed here several years back.
https://www.diyaudio.com/community/threads/beyond-the-ariel.100392/page-606

Searching [ james romeyn rear reflecting tweeters ] there’s some notable hits, such as post # 10,590. https://www.audiocircle.com/index.php?topic=149798.20

Also, here https://www.diyaudio.com/community/threads/what-are-the-benefits-of-rear-firing-tweeters.222708/

https://www.diyaudio.com/community/threads/late-ceiling-splash.332507/

But given the HF response of the DCM-50, what would be your reasons for adding supertweeters, and utilized in that manner? Whatever new conclusions may be drawn for such solutions with a given speaker build, I hope there might now be renewed and indepth discussion of specific HF drivers used in such rear wall and/or ceiling reflecting configurations.
 
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I really like Beryllium, but hoo boy, is it expensive. The cheapest route seems to be used JBL drivers with blown diaphragms, carefully cleaning the gap, and installing the Radian replacement diaphragms.

Regardless of cost or the appropriate horn (s), based on what you've listened to and/or would expect due to their construction (e.g. diaphragm composition), how might you rate these?

https://www.eighteensound.it/en/products/hf-driver/1-4/16/ND1480BE

https://www.usspeaker.com/radian 745neoBepb-1.htm

https://usspeaker.com/rcf nd950.2.0-1.htm

https://usspeaker.com/B&C-DCM50-1.htm

And would that choice also be governed by the quality of one's source material: Well mastered CDs, but also IF lots of much treasured music only available on compressed and/or "congested" sounding CDs?