Open source Waveguides for CNC & 3D printing!

Thank you augerpro for your great work for the DIY community! Had a wave guide machined, and donated to your gofundme. Very happy with the result.

In my excitement to have the waveguide ready to go, I had it built too early on in my planning process. I've gone around in circles trying to find the correct mid for my three way, and decided the tweeter I'd chosen won't work given other constraints, mid driver size etc. The upshot is I need to swap out the tweeter to one that will cross lower.

What do I need to consider if using the SS D3004/660000 (6.5x1.2 rB SS) waveguide with a T34A tweeter? Will that work? I think the T34 waveguide is slightly shallower?
 
That's for the power rating! Resonance frequency is about 500Hz and the Waveguide will add some sensitivity ... no problem to cross at 2000Hz, very likely also 1800Hz is easy. What's your midrange?
Ah right! The datasheet is unclear with the “operating range” wording. I dug up the tech note on power handling. Thanks, I never would have guessed that. Midrange is Purifi PTT6.5M, the downside being you need to stay well away from 3k. Even with a 4th order slope at 2k there’s a nasty knee in the slope about 15db down.

Thanks for all the tips fellas, maybe I’ll stick with the SS with this waveguide then.
 
A small one that I posted T34A Small Waveguide

The bigger one that simulates better is printing now.

Screenshot 2024-06-01 at 8.49.58 AM.png


Trying to decide on the best strategy and material for the prototype

IMG_1280.jpg
 
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I am trying to decide on a tweeter to match to the Morel MDM 55/CAM 558 @3-3.5KHz (LR2). My reasons for wanting waveguided tweeters are controlled dispersion and directivity matching at crossover point. I was planning on using the SB21SDC, but have seen comments that its perceived fidelity is not quite up to snuff with some of SB's other offerings. Does anyone have any first hand experience using the SB21SDC's in auger pro's waveguides? (Will probably use 4-5" since I don't need them to play low)
 
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Where did you see negative comments about the SB21SDC? BTW, if anyone looks at HiFiCompass's measurements, I'm certain he had a defective one. Compare it to the SB21RDC but also to the SB21SDCN an SB21RDCN. The SB21SDC is an outlier and it shouldn't be because it has the same motor as the 21RDC and same dome as the 21SDCN. The other three in the family all measure similarly other than Rs having different frequency response than Ds.
 
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Where did you see negative comments about the SB21SDC? BTW, if anyone looks at HiFiCompass's measurements, I'm certain he had a defective one. Compare it to the SB21RDC but also to the SB21SDCN an SB21RDCN. The SB21SDC is an outlier and it shouldn't be because it has the same motor as the 21RDC and same dome as the 21SDCN. The other three in the family all measure similarly other than Rs having different frequency response than Ds.
Good to know about hifi compass. Haven't seen anything negative per se, just that it isn't the screaming value that other SB tweeters are performance wise

How do you like the SB21SDC in comparison to say the SB26ADC? That's another one I was considering, although I wasn't sure if it has any advantages besides the ability to be crossed lower. It would be cool if SB had a 21mm aluminum tweeter