Tease Tease
No phase shield is looking best so far, which is nice for manufacturability. Still have to measure the 6.5" then I can start posting results.
No phase shield is looking best so far, which is nice for manufacturability. Still have to measure the 6.5" then I can start posting results.
I have a pair of sb26adc's here that are cold and lonely, longing for a 6.5" wave guide to match to the purifi 6.5
Ok first results are SB26 5" version H. It doesn't get much better, so I'm calling the 5" done. Note whether a phase shield is included.
For fun I wanted to go with a more round mouth, so here is a 5" but with mouth aspect ratio of 1:.80
Not really anything to gain. But I will try a strictly circular mouth just to be sure I didn't go down the wrong path when went with elliptical mouths early on when the first circular mouths weren't very good.
Now the Bliesma T25B tweeter. I really like that the best response are without phase shield. I did a 5" with my normal 1:.618 aspect ratio mouth and another using 1:.80, two 6" of varying depth, and one 6.5".
A note about the high frequency spike @48khz: this is a combination of the mic calibration no longer being very accurate and the math of the FFT. None of these tweeters actually spike the high.
For fun I wanted to go with a more round mouth, so here is a 5" but with mouth aspect ratio of 1:.80
Not really anything to gain. But I will try a strictly circular mouth just to be sure I didn't go down the wrong path when went with elliptical mouths early on when the first circular mouths weren't very good.
Now the Bliesma T25B tweeter. I really like that the best response are without phase shield. I did a 5" with my normal 1:.618 aspect ratio mouth and another using 1:.80, two 6" of varying depth, and one 6.5".
A note about the high frequency spike @48khz: this is a combination of the mic calibration no longer being very accurate and the math of the FFT. None of these tweeters actually spike the high.
For fun, 0/30/60 degrees of the SB26STAC on vH waveguide:
Quite similar to SB's own little waveguide on this dome: SB26STWGC-4 / Fabric – Sbacoustics, though their's looks to only add maybe 1/4" of depth when aligning acoustic centers.
Quite similar to SB's own little waveguide on this dome: SB26STWGC-4 / Fabric – Sbacoustics, though their's looks to only add maybe 1/4" of depth when aligning acoustic centers.
What are your thoughts on having an exposed beryllium dome? I love the idea of the T25B in a waveguide - and your results confirm that this could be an excellent way to go - but I just can't accept the risk of damage.
Hello Brandon,
Excellent work as usual !
For The Bliesma T25B, it looks like the clear winner is the 5 x.75 with the 1.8 mouth ratio and without phas shield !
I was able to get a CR10S printer recently and would like to give it a try. Would you mind sharing the stl file please and also Cura recommendations for the printer (profile and filling) as I'm a complete noob on 3D printing
And Paul, for possible dome damage, I think that it's possible to put a very thin mesh on the front plate ?
Excellent work as usual !
For The Bliesma T25B, it looks like the clear winner is the 5 x.75 with the 1.8 mouth ratio and without phas shield !
I was able to get a CR10S printer recently and would like to give it a try. Would you mind sharing the stl file please and also Cura recommendations for the printer (profile and filling) as I'm a complete noob on 3D printing
And Paul, for possible dome damage, I think that it's possible to put a very thin mesh on the front plate ?
Sometimes using just the 0 and 40 degree measurements are little clearer. Here are the Bliesma T25B results.
I'm not personally worried, but I don't have kids, so...I can try some protection but it might be a few weeks.
I use Simplify3D, but the main changes I made were .12 layer depth, and 4 layer walls, and turn supports on. Did a lot experimenting to print these facedown so the tweeter interface was high quality, lots going with the lip, locating pegs, and in the case of Scanspeak tweeters, just a lot of shaping for a correct seal. But I couldn't get anything to print the walls smoothly that way, so I switched to printing face up with supports turned on. Lip looks decent, but I need to do a full print and see if it measures like the ones above.
My son does prototyping on a pretty fancy resin printer. Not sure what file types he works with but I’m sure I can get him do some prints for you guys. Let me know what the file extension is and i’ll ask him. The resin he uses take paint very well too.
I’ve been kicking around waveguide retrofits to the Peerless Corundum tweeter who’s low Fs and roll off look like a real winner with a lens
Peerless DA32TX00-08 1-1/4" Corundum Dome Tweeter
I’ve been kicking around waveguide retrofits to the Peerless Corundum tweeter who’s low Fs and roll off look like a real winner with a lens
Peerless DA32TX00-08 1-1/4" Corundum Dome Tweeter
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.stl files are the standard for 3D printing as far as I know. I have .step files too, but those are for the CNC peeps.
I agree this is a great tweeter and would be very interested in seeing any of the waveguide designs you've come up with!
Brandon,
I guess you use SoundEasy which I never try, would it be possible to change the scales ?
For example, 100Hz to 30 kHz for x (to avoid mic inaccuracy) and increase vertical resolution (55dB to 105dB).
This would certainly help to select the proper wave-guide.
And thanks for the 3D printing tips. So it look's like it's not so easy to get a good result...
Jean Claude
augerpro - I in the planning phase of a 3-way tower build involving an 8" woofer, 5.5" mid, and a 1 1/8" dayton silk dome tweeter (DC28F-8). The dayton tweeters are leftover from an old automotive install that I did when I was younger, and as a result the faceplates are a bit hacked up and I need to fabricate replacements.
In my build thread a member suggested I look into making waveguides since I need to do some fabrication anyways.
Do you think that any of the waveguides that you've designed might work reasonably well for my tweeter? I have access to various 3D printers along with CAD software (Solid Edge & Siemens NX), so if you can point me to one of your STEP files that might have a workable, I'd be interested in doing an A/B comparison with a regular flat faceplate.
In my build thread a member suggested I look into making waveguides since I need to do some fabrication anyways.
Do you think that any of the waveguides that you've designed might work reasonably well for my tweeter? I have access to various 3D printers along with CAD software (Solid Edge & Siemens NX), so if you can point me to one of your STEP files that might have a workable, I'd be interested in doing an A/B comparison with a regular flat faceplate.
Depends on which throat size would accommodate that tweeter. I would switch the tweeter out for something else if a waveguide is required🙂
Yes, when I get a chance I can do this. So as not to waste time, what models are you interested in?
Not required, but the idea was tossed out by another member since I was planning to fab new faceplates anyway 😉
I have a pair of T25B and plan to use them to match with the 6.5 inch Purifi mid woofer. If I understand this correctly, theoretically the 6.5 inch wave-guide should be the best match but I don't think it's all that critical (from 5 to 6.5 inch).
If this is correct, I would like to try the one which will give the best homogeneous response and thus my demand for extended scales to be able to select...
On your side, from your experimentation, which one you consider gave the best result ?