I'll be matching this tweeter with the SB16PFC woofer early this summer. I'll post when I get measurements of the prototype box.
I am currently in the process of putting together a 3-way with the SB26ADC and an SB15NBAC30 for tweeter and mid. I was wondering if people had experience pairing the mids with one of the Augerpro waveguides.
I am thinking that the 4" may work (hopefully better than stock) and fits on my current front baffle. I could also move to the 5" if need be if it would lead to a performance benefit. Also, would the PS be necessary in something like this? Any suggestions?
I am thinking that the 4" may work (hopefully better than stock) and fits on my current front baffle. I could also move to the 5" if need be if it would lead to a performance benefit. Also, would the PS be necessary in something like this? Any suggestions?
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What crossover frequency and slope?
I think the phase shield is worth it. Where are you sourcing the waveguide from?
I think the phase shield is worth it. Where are you sourcing the waveguide from?
I plan on crossing between 2-2.5k, ideally around 2.2k. Don't know the exact slope yet but it will be 2nd order if I can manage that, maybe 3rd if need be, all passive.
I will most likely be resin printing these myself and finishing/painting (which is good because of hard dome and phase shielding). I might be able to CNC them if need be though but would remove the phase shielding.
I will most likely be resin printing these myself and finishing/painting (which is good because of hard dome and phase shielding). I might be able to CNC them if need be though but would remove the phase shielding.
Hmmmm. I think I'll go for the 5" then if you'd recommend it. I ran the baffle diffraction sims with the smaller baffle chamfer and diffraction was basically the same as compared to the larger one. Any opinion on this?
I don't know how big smaller and larger are, but there is usually quite a bit of difference. What software did you use? I didn't think there were any other than ABEC that could model that enclosure. I think the 4" could work fine. but there will be a difference between it and the 5" at that crossover frequency.
The corner chamfer would go from around 58 mm to 50 mm. I used a similar process as hifijim used in his speaker builds in Vituix to simulate the baffle diffraction. He mentions that in Vituix you can model each driver individually and use a full width radius (differnt for each individual driver) and it yields similar results to what his actual testing produced. I had tried to get a license for ABEC through my university at the time but I figured it may have been overkill and not worth the hassle for what I needed.
Yeah 8mm probably doesn't do much for a chamfer that big. So you could do the 5" pretty easily.
Quick update on my SBAcoustics "ceramic" standmount design. Following is the Klippel measurement for the active version. I think a 250hz boost filter may have been off, but oh well, you get the idea regarding power response. Added some other target designs for comparison. Before I post the design I'm going to try another box shape to see if I can get the same response, but with a less complex passive crossover.
Over the last 2 decades, I have seen plenty of DIY projects that will outperform the vast majority of "professional" speakers easily.
In fact, ever since Erin started testing, it totally proved my suspicion based on a few of my own measurements, which is that the majority is meh at best.
We are not even talking about nuances, but just fundamental basics that are already wrong or a freq resp that looks more like a mountain range, terrible resonances etc.
Which is mind boggling, if you think about proper literature about this, like Floyd Toole's book that has been available since 2008 or so?
Even before that, there was already a pretty good sense about the importance of directivity and freq resp.
I'll post them free here and on my website. I took a long time with this one since it sets the design elements of several families going forward. I'll be making prototype boxes (all stand mount at first) early summer for the following driver combos: Satori MW16TX & TW29BN/TXN, SB16PFC & SB21SDC, SS Discovery 18W & SB26STAC (or SB29SDAC), and possibly some Dayton Reference versions.
I'll try to find my QC from last fall. But yes, I was very satisfied (relieved?) when I compared them. Basically it ended up:
<150hz = same sensitivity but rolloff was a bit different. Makes sense given mine was a combined port+near woofer response. I've never really put a lot stock in this measurement anyway since accurate T/S will generate better box response in software.
150hz - 1000hz = This is where the biggest difference was. But in a way that my measurement is still accurate, but smoothed. Where the Klippel has some little ripple with its high resolution, my response was like a slightly wavy line that touched the tops of the ripples on the Klippel response.
1000hz - 6000hz = dead on to the Klippel
above 6000hz = slight deviation that became more noticeable >10khz. Maybe 1.5dB different around 12khz or so IIRC. So basically the top octave and bottom octave diverged, but with the middle in good agreement.
I think that is a bit open for debate, since Klippel is using a "averaging" method (to overly simplify their method in one word), this always leads to some bumps and things.
Unfortunately they are not very transparent about this.
Especially below 500Hz, or rather below the lowest point of the impedance, a speaker just follows 100% piston behavior. Even more so when the cabinet is small enough (no internal resonances).
The question that should be asked here, is where is this little ripple coming from?
At low SPL's that also can't be panel resonances.
This I find the danger of such Klippel like system.
You get a nice overall picture, but without zooming into certain things, it's just a total guess where certain things come from.
A simple near-field measurements with a BD plot, distortion etc will often tell you these things much better.
Above 6kHz is probably just difference in microphone calibration and/or position.
Move your mic just a couple of degrees or so, and you can already find differences.
Would you mind sharing your own measurements as well, as a one-to-one comparison?
I think it would be absolutely fascinating to compare the two! 🙂
My final measurements, or the QC I did back in the fall?
Agreed on the top octave. I think that is where you're are going to see a difference between methods (near vs far) no matter what you do.