Open source Waveguides for CNC & 3D printing!

It's not theoretical as changing the vertical spacing has an obvious and audible difference. It's less solving a problem and more choosing a different set of compromises.
I agree on the audible part, but merely questioned which compromise is worth pursuing for maybe minute gains vs a more overall good reproduction - like B&W's super rigid cabinets vs good dispersion - just an example.
Now I see people simply dropping the classical tweeter/midrange combo and buying a KEF speaker to take it apart and use the uniQ driver for their project - namely to conquer the horizontal vs the vertical challenge.

I have a pair of BMS 6CN160 coax's that I will fiddle with soon, to see how much of a difference it can make in contrast to the waveguide-way.
 
Example: it is just one compromise out from system designer restriction list allowing whole new set of probable concepts expanding design space. Thinking a system concept is now freed almost completely from the c-c spacing at least for some applications. This allows freestanding waveguides for example, further separation of concerns. Or circular symmetric ones which are a bit faster to sim and easier to manufacture at home. Easier manufacturing in general as less tight tolerances, divider panels inside enclosure etc. One doesn't have to end up on a such system, just an extra freedom of choice. Any system is a set of compromises including the coincident variety.
 
Example: it is just one compromise out from system designer restriction list allowing whole new set of probable concepts expanding design space. Thinking a system concept is now freed almost completely from the c-c spacing at least for some applications. This allows freestanding waveguides for example, further separation of concerns. Or circular symmetric ones which are a bit faster to sim and easier to manufacture at home. Easier manufacturing in general as less tight tolerances, divider panels inside enclosure etc. One doesn't have to end up on a such system, just an extra freedom of choice. Any system is a set of compromises including the coincident variety.
I agree again. I can clearly see that classical tweeters would make rather big dips when mounted directly on the baffle, rather than being flush, also best asymmetric.
A Seas DXT definitely needs a narrow baffle to works its best, and an Augerpro design accepts a more standard square baffle without issues that I have come about - yet.
What I'm trying to get at... is that maybe we should work a little backwards and start by defining the compromises that we can't live with, and then gather the best possible solution in what options we have left.
For example. I like a slim tower, because it looks better when I have a small midrange/waveguide combo on top. That compromises a bigger woofer... and so on.
That's why I believe that sometimes we are chasing a near perfect theoretical and maybe also practically the best solution in one end, but slightly neglecting the total result. It's like every type of speaker, is a universal overall experiment towards better sound.
 
Yeah, more than often people build speakers which don't have the sound top priority but size or cost or some fashionable set of drivers as the main priority, or just the looks. Which is backwards if going strictly for audio quality because it might not need the drivers or fit the size and probably looks awkward as well:D I'm sure everyone would prefer best possible absolute audio quality, it is just that reality comes into way and limits the options, size and looks and of course cost being the most obvious ones. Best possible for application is nice balance of compromises, and not everyone remembers to think about it, too deep.

For sure augerpro waveguides are a top deal when it suits the system! In my opinion all tweeters/systems would benefit from a waveguide, controlled directivity. Also visual appeal is at least half of the enjoyment. At least it needs to be tolerable, which is why I'm planning to mount against wall, hide the big woofers into furniture, camouflage paint etc. Want them to disappear, I only need good sound :)
 
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Are many of these issues more of a theoretical type, rather than a real problem/challenge to be dealt with?

Because when I sit and listen now - I really have to struggle to find problems with the sound in any type of music with either strings, bells, horns, female S's, piano or anything like it, except in the woofer range between 80-500Hz, where a very slight room induced resonance can be heard in some tracks.

The combo of a 5" midrange and the 5" oval waveguide, works like something I have very rarely heard anywhere - no matter the price. It's exceptional clear, detailed and the phantom image is dead center and very focused - like I'm not even thinking about the speakers - sound just seems to emanate from a fictive speaker between the speakers - when the music is made to fit this illusion of course. Some music makes the sound almost come from a source to the side of me.

So what are your references or maybe specific tracks, that make you want more or miss something? - If this i not too much OT.
I also wonder how much improvement, real world audible improvement, comes from managing the DI curve until it matches some ideal line.

The CTA2034 standard contains formulas for various derived curves. The sound power curve is based on math (solid angle geometry), so there is no statistical assumptions baked into the calculation of sound power. The other curves, however, are based on assumptions about the listening room. The Early Reflections curve and the Predicted In Room curve are based on what was measured in a series of typical listening room. In my case, my measured in-room response at the listening position does not match the PIR curve, nor the sound power curve. It most closely matches the on-axis curve. I have a -3 dB hole in my sound power curve between 1k and 2k, but it is not measurable at the listening position. My next project will have a much more even DI curve, and it will be interesting to see what I perceive as the differences.

So the point is that all rooms are different. A speaker with excellent spinorama performance is far more likely to sound good in a wide variety of rooms than a speaker with uneven directivity. But that uneven directivity speaker may be well suited for a particular room. Tmuikku has several posts which discuss how variations in vertical polar responses might benefit or hurt the sound in various rooms. This is an interesting line of thought.

j.
 
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I also wonder how much improvement, real world audible improvement, comes from managing the DI curve until it matches some ideal line.
Nil, throughout all the research ever conducted that I have read or seen, there has never been a specific directivity that has been unanimously preferred.

Whilst it is human to look for a target or goal, and a flat line or specific slope is attractive as an idea to fit to, that can only be helpful in determining which concepts allow that sort of directivity without other severe compromises.

Maybe this is how others perceive the information being provided that it is fitting the DI to an idealized slope. I see it as a way to try and balance the compromises in a design. In a speaker without a waveguide where the tweeter is on anything other than a minimal baffle there will be a battle between on and off axis that has to be managed. The solution is a waveguide or faceted baffle. With vertically spaced drivers there is a balance between vertical nulls and how they fit with the overall power and early reflection response. The solution to this problem is going coaxial or keeping the drivers within 1/4 wavelength or up to a 1/3 wavelength. Both of those present their own issues in a much different way than a waveguide or faceted baffle does so they are much less used in practice, leaving a choice on how to balance the compromises.
 
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Yeah, more than often people build speakers which don't have the sound top priority but size or cost or some fashionable set of drivers as the main priority, or just the looks. Which is backwards if going strictly for audio quality
Actually it's not backwards, it's just an intrinsic part of the the variables in the equation.

Unless you have a dedicated room for listening, but most people have to get by with what they have.
Although I agree to some extend, since it doesn't make any sense to go for very expensive drivers or amplifiers and still have a room that's is acoustically total garbage. Something you see way to often (actually more than not)
Still, the sound of many recordings is artificial to begin with.

Something that only exists in recordings, but you will never actually be able to hear in reality.
 
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I had a friend modify the STEP files to the SB26 waveguides to make the outline rectangular for ease of building.
I haven't sanded these yet, he did the 3D printing at work and sent them to me.
 

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I've never compared the two, so I couldn't say. They measure almost identically.

But I do like the white diaphragms, so I'm using the CDC/CAC in my current project too!
Agreed - looks means a lot too, and the even though I already own the ADC and love it... it's tempting to buy the CDC just for the looks :giggle:
I find it interesting that a direct radiating tweeter like this one seems pretty "hot" in the high frequencies - needing maybe a house curve EQ.
https://www.audiohobby.eu/en/stereo...eka-ceramic-diy-speaker-kit-by-stereoart.html

Whereas, when a waveguide is used, the same driver has a smooth falling response off-axis, which seems to fit most listening preference.
 
digitalthor> I would agree that the top octave is often better with a waveguide, so maybe they keep the "sparkle". But the higher DI in the low end of the passband has made for a "calmer" and less splashy sound than the same tweeter without a waveguide. Bright would not be a description I would use for a waveguided tweeter vs being baffle mounted.

YSDR> yeah, my printer is clogged. But you can try them yourself if you want, they should be very close to the first couple variants tested a few months ago.
 

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digitalthor> I would agree that the top octave is often better with a waveguide, so maybe they keep the "sparkle". But the higher DI in the low end of the passband has made for a "calmer" and less splashy sound than the same tweeter without a waveguide. Bright would not be a description I would use for a waveguided tweeter vs being baffle mounted.
Exactly what I experienced... namely that direct radiating tweeters, seem to sound more "sparkly" but less precise, because they send out more reflective energy in the room, instead of a waveguide, that focus the sound more evenly to the listener.
I really enjoy this waveguide - you did great work with it (y) :D
 
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I now play with SB26ADC in a pair of quickly printed 5" Augerpro waveguides. Works really great :giggle:
I think the SB26CDC looks cooler... so I know that I can easily be biased, when wondering to maybe buying that instead. But is there anything remotely better or different in the CDC vs the ADC?
I’ve not measured them, but SB Acoustics says they’re interchangeable in the Bromo kit. There may be infinitesimally small difference; which might be trumped by colour preference in sighted listening tests.

I honestly think Its a case of colour preference/attraction.

the white cones suit lighter timber, IMHO