Open source Waveguides for CNC & 3D printing!

Last waveguides I got printed ,with resin they almost feel like silk and have a weird light refraction effect but they are I really nice looking in person. This is the waveguide mabat posted in the ath thread it work as modeled
20230714_210834.jpg
 
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Erin reviewed the Philarmonic Ceramic Mini, using -what I suspect- is using the SBAcoustics SB26CDC-C000-4 and the 5″ SB15CAC30-4
and check those distortion plots!

Imagine a small (sealed) bookshelf with the same drivers plus an @augerpro waveguide to help the directivity and performance at the XO, and you have a killer speaker! (to use it with 1+ SW of course).

https://www.erinsaudiocorner.com/loudspeakers/philharmonic_ceramic_mini/

Yeah 5 or 7 + with sub(s) would make a great HT setup.

For music, the region between 100-300Hz would still limited by this setup.

For years people like Dennis and Troels have been saying that for music, a real 3 way with a good sized woofer eg. 8”+ will give more authority in the important 100-300Hz “power” region of bass instruments, and the measurements are consistent with this, as you see a rise in harmonic distortion below 400Hz

I would personally prefer Dennis’ full sized BMR floorstander as a music first speaker. Dennis has a refreshingly honest approach and if you asked him he would give guidance in terms of what would suit your room/music tastes.

If you really must have the SB15/SB26CDC
Jim Holtz/Curt Campbell already has a design with this mid and tweeter and a pair of 8” woofers called Anthology II.

Add subs later, if one felt it was necessary.
 
Ok, here are the 8" waveguides for the T34B. Also included a new 6.5" elliptical mouth with a higher aspect ration (1:.83). Also included a new 6" elliptical waveguide for the T25B (used my new family of speakers). I've decided to revisit the circular mouth on the SB26 family. The first is a 6.5" model, and it looks good, I'll move on to the other sizes when I have time. I've updated my website to include the new design

ORSLblN.png
Thanks for the design . I will try this design for a 2 way speaker with the T34 B and the new Purifi 8 inch (with passive radiators)
I have a question for mounting the T34 B : do I have just to remove the protective grill , and screw it at the rear side, or did I have to dismantle it ?
 
Unfortunately Meniscus is closing down.

I don’t have any further details.
That's a bummer since there aren't many floorstander designs out there that use SB ceramics drivers. I know a couple that do:

1. Jeff Bagby/Javad Shadzi Ceramico (open source, detailed plans on facebook)
2. Rick Craig (Selah Audio) Ceramica (was available as kit, unavailable now after Rick's passing)

The Ceramico looks good on paper since they use simple 2nd order electrical XO on all drivers but I don't think 2nd order low pass in the midrange is sufficient to surpress woofer breakup, especially at higher SPL levels.

There's another design by Paul Kittinger called Sonatello that you can possibly swap the drivers out with ceramic ones but it has a few undesirable design choices (at least for me) like diffraction issues due to midrange driver placement at the top of the speakers and far CTC spacing between the midrange woofer and the midbase woofer. But the design looks very intriguing due to its tapered TL design and its midbass driver placement at the bottom that you can basically eliminate BSC and increase overall system sensitivity due to floor boundary bass gain.

I'm excited to see what @augerpro can come up with his floorstander design!
 
Question for all you box alignment experts. I've been toying with slightly undersizing the box for the SB17CAC-4 to allow for a higher tuning frequency, without creating peaking. These SB drivers often look great with larger boxes and tuned in the 30's, but these are small drivers and i'm more concerned that they can handle kick drums well. So I'm looking to tune more in the 40s. Then I notice Erin's recent tests of the Philharmonic and Revel speakers using these same SB drivers and they are tuned really high - 50-ish hz. (I realize the Phil is a 15cm but they behave similar to the 17cm).

My question is as you undersize the box and tune higher - though not the extent of Philharmonic and Revel, are there downsides or pitfalls?
 
I trust the guys at the polish DIY audio forum. Those people are experts, according to a guy who shared his opinion (zap audio, a professional builder) those drivers work better at smaller boxes than usual, and need smaller bsc, even no bsc at all. Haven't tried his advices but I would bet he is true. Larger box gave me sluggish, one note bass.
Also Michael Chua agrees with sb17 in smaller boxes, check his sb17nxr builds (one in 17 liters and one in 13liters with the latter having much betterfeed back)
Erin's review conclusion on Sb17cac35-4 shows some strong evidence for sealed box with subwoofer crossed at 80hz and that would be pretty much optimal for these drivers.
 
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Augerpro: 15l 35Hz or even smaller 12l 38Hz are the alignments I would start with. From multiple experiences with Sb17CAC and SB17 drivers generally, I would not recommend higher volume at all, really does not sounds good.
Buchardt S400 sounded quite ok in the bass and lower midrange, and it is small loudspeaker, I would estimate internal volume ~12liters.

I also heard 2xSB17CAC35-8 in closed enclosure, it was lacking the bass, so really good only when supported with the sub.
 
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I trust the guys at the polish DIY audio forum. Those people are experts, according to a guy who shared his opinion (zap audio, a professional builder) those drivers work better at smaller boxes than usual, and need smaller bsc, even no bsc at all. Haven't tried his advices but I would bet he is true. Larger box gave me sluggish, one note bass.
Also Michael Chua agrees with sb17 in smaller boxes, check his sb17nxr builds (one in 17 liters and one in 13liters with the latter having much betterfeed back)
Erin's review conclusion on Sb17cac35-4 shows some strong evidence for sealed box with subwoofer crossed at 80hz and that would be pretty much optimal for these drivers.
+100.......I could not agree more.
 
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