Hi again!
I worked on the design this weekend. I am trying to match the off axis dispersion of the mid and a tweeter. I realign the frequency, adjust the unit so the two graphs match.
I think I tried at least 10-15 candidates. I dont have a lot of data for tweeters + waveguide sold separately. A very good candidate is the Satory Beryllium with waveguide.
https://sbacoustics.com/product/satori-tw29bnwg-4-beryllium/
Seems to be an excellent tweeter. On the expensive side for sure. One negative is the longer distance between the mid and tweeter compared to smaller tweeters with waveguide.
The graphs are not 100% perfect as the off axis are not exactly the same (22.5 vs 30 degrees, ...). But gives a good idea if potential good match or not.
Here the result for the Satori. Crossed at 2500kHz-3000kHz would be a very good match.
With the same methodology, other good candidates are the Seas DXT27, T25CF001 (the same one in the previous ATCs), SS 990000, ...
Even if I see some information on waveguide for a Seas T35, I don't find really a way how to purchase them.
Thanks for your comments! Enjoy the week.
I worked on the design this weekend. I am trying to match the off axis dispersion of the mid and a tweeter. I realign the frequency, adjust the unit so the two graphs match.
I think I tried at least 10-15 candidates. I dont have a lot of data for tweeters + waveguide sold separately. A very good candidate is the Satory Beryllium with waveguide.
https://sbacoustics.com/product/satori-tw29bnwg-4-beryllium/
Seems to be an excellent tweeter. On the expensive side for sure. One negative is the longer distance between the mid and tweeter compared to smaller tweeters with waveguide.
The graphs are not 100% perfect as the off axis are not exactly the same (22.5 vs 30 degrees, ...). But gives a good idea if potential good match or not.
Here the result for the Satori. Crossed at 2500kHz-3000kHz would be a very good match.
With the same methodology, other good candidates are the Seas DXT27, T25CF001 (the same one in the previous ATCs), SS 990000, ...
Even if I see some information on waveguide for a Seas T35, I don't find really a way how to purchase them.
Thanks for your comments! Enjoy the week.
The waveguide for this tweeter isn't even working well until 20kHz ... for that price I would expect more. But it's not easy with these wide surround 1" drivers.
I would for sure not use an old design like the 990000 ... I had a speaker with the 97000 and as these are not bad tweeters - it's no comparison to a modern Beryllium one.
I would for sure not use an old design like the 990000 ... I had a speaker with the 97000 and as these are not bad tweeters - it's no comparison to a modern Beryllium one.
That's not necessarily a problem. Just use a slightly lower crossover frequency than ATC's 3.5 kHz and you can have the same c-c distance/wavelength ratio as the 3-way ATCs have.
I must say that I am a bit lost. Looking for a "very good" tweeter with waveguide matching the ATC dispersion at around 2500-3000kHz with a tweeter + waveguide combination that is commercially available or findable on the used market... The Satori was for the me a super nice option.
Thank you for the comment on the c-c distance/wavelength ratio. Interesting. I have calculated that the distance between mid and tweeter for ATC speakers is around 140mm (from the picture). Wavelength at 3500kHz is 97mm. The ratio is 142%
At 3000kHz, that would mean a distance of 161mm, at 2500Hz 193mm. My first estimation gives a distance of approx 170mm, very close to same ratio of ATC if crossed at 3000kHz. Another good point for the Satori with waveguide.
The troels waveguide for the Seas T35 is almost impossible the find... That would be maybe the best choice. The T35 without waveguide is not a bad match with ATC mid at 2500-3000kHz but others are better. See below.
So for now, even if not perfect for the price, I think the Satory Beryllium with waveguide is still a good candidate.
Bliesma + waveguide seems to be another very strong candidate but on the (very) expensive side and no commercial waveguide.
Other options or DIY waveguide I could use with another tweeter that would make sense? Any tips?
Thank you for the comment on the c-c distance/wavelength ratio. Interesting. I have calculated that the distance between mid and tweeter for ATC speakers is around 140mm (from the picture). Wavelength at 3500kHz is 97mm. The ratio is 142%
At 3000kHz, that would mean a distance of 161mm, at 2500Hz 193mm. My first estimation gives a distance of approx 170mm, very close to same ratio of ATC if crossed at 3000kHz. Another good point for the Satori with waveguide.
The troels waveguide for the Seas T35 is almost impossible the find... That would be maybe the best choice. The T35 without waveguide is not a bad match with ATC mid at 2500-3000kHz but others are better. See below.
So for now, even if not perfect for the price, I think the Satory Beryllium with waveguide is still a good candidate.
Bliesma + waveguide seems to be another very strong candidate but on the (very) expensive side and no commercial waveguide.
Other options or DIY waveguide I could use with another tweeter that would make sense? Any tips?
Another regular sized tweeter with waveguide for example is the Morel CAT 378.
https://www.dibirama.altervista.org...0-morel-cat-378-tweeter-1-8-ohm-400-wmax.html
https://www.dibirama.altervista.org...0-morel-cat-378-tweeter-1-8-ohm-400-wmax.html
I know you'll think I am an idiot, but I feels this is one of the weirdest posts around here. It seems you simply listed a bunch of expensive drivers from reputable manufacturers, assuming they will make for a good loudspeaker. The concept for your speakers seems not based on acoustics or electronics, but on names.
If you want to build good speakers, think about the acoustics that you want to achieve, and what it takes to get there. Once you know what you're doing, the names will become irrelevant.
Oh, and just as a heads up: your speakers may sound a lot better with a properly built passive filter than with one of those minidsp thingies.
You still think all DSPs sound like your 200 bucks 2x4HD trials? 😉
But you are totally right with concept! Looking for a T35 to cross it over at 3kHz ... ages old ScanSpeak tweeters ...
When you can accept the behaviour of the Satory Beryllium with waveguide (it's not THAT bad, just not perfect) you are good to go.
A pair of Scanspeak Discovery 26W/8534 could be an option should work well in a 100L sealed cabinet.
I was referring to minidsp, not "all DSPs". But that's not the point here. My point is that I can't see any system concept.
Hi everyone, thanks again for all your inputs and information. Maybe some have missed it in previous post but I have already purchased the woofer. TD15H Acoustic Elegance that I have purchased used. Will use the woofers sealed in a 70l cabinet with bass boost (linkwist transform). Received the woofers yesterday. Impressive beasts...
For the tweeters, I think I have came to some conclusion. I have looked at many off-axis responses for different tweeters and try to match with the ATC around 2800-3500 Hz. With a waveguide of around 10cm, I can have a nice match at the crossover frequency on what I call on the right side (higher frequencies). With waveguide larger than 10cm, I can have a nice match on both sides...
Here a nice match at approx 3500Hz with Wavecor tweeter. Same can apply for similar sized waveguides. Match is not that good at lower frequencies. Morel 378 would show similar good match at crossed Hz and on the right side...
Here Bliesma T25b with a 15cm waveguide. Crossed at around 3.2, and good match both on the left and right. The Satori BE with waveguide would show similar results (at least close to crossover point)
The scanspeak 990000 has also a nice match on both sides (not as nice compared to 15cm). Waveguide is 13cm. But seems not to be a recommendation here even if seems to be more than good enough, could you elaborate the why? Here below the result.
So, my conclusion for now is that I should look at waveguide of approx. 13-15cm to get a nice match around the crossed frequency (left and right). Was maybe straightforward to you... 🙂
The Satori BE with waveguide is still a good commercial option.
Other options with DIY are infinite. Here using the XT25 with WG 300
https://heissmann-acoustics.de/en/test-vifa-xt-300-xt25tg-waveguide-wg-300/
So, I think I have a strategy. But not sure between
Does this make sense?
For the tweeters, I think I have came to some conclusion. I have looked at many off-axis responses for different tweeters and try to match with the ATC around 2800-3500 Hz. With a waveguide of around 10cm, I can have a nice match at the crossover frequency on what I call on the right side (higher frequencies). With waveguide larger than 10cm, I can have a nice match on both sides...
Here a nice match at approx 3500Hz with Wavecor tweeter. Same can apply for similar sized waveguides. Match is not that good at lower frequencies. Morel 378 would show similar good match at crossed Hz and on the right side...
Here Bliesma T25b with a 15cm waveguide. Crossed at around 3.2, and good match both on the left and right. The Satori BE with waveguide would show similar results (at least close to crossover point)
The scanspeak 990000 has also a nice match on both sides (not as nice compared to 15cm). Waveguide is 13cm. But seems not to be a recommendation here even if seems to be more than good enough, could you elaborate the why? Here below the result.
So, my conclusion for now is that I should look at waveguide of approx. 13-15cm to get a nice match around the crossed frequency (left and right). Was maybe straightforward to you... 🙂
The Satori BE with waveguide is still a good commercial option.
Other options with DIY are infinite. Here using the XT25 with WG 300
https://heissmann-acoustics.de/en/test-vifa-xt-300-xt25tg-waveguide-wg-300/
So, I think I have a strategy. But not sure between
- Relatively cheap XT25 and WG300
- SS 990000 (not too complex to find used)
- Satori BE with waveguide (now in discussion with someone selling a used pair)
- Bliesma T25B with DIY waveguide (if I can find a pair and find a compatible waveguide... )
- so many DIY options...
Does this make sense?
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The 9900 is a good tweeter, but it was not used extensively when it was new. I believe this is because people did not understand how to deal with it's waveguide behaviour back then (including me).
That said, a waveguide / tweeter system works best with a small dome, or a ring radiator. That's why we used the R2904 for the waveguide stuff in the OSMC speaker (see my signature for links).
That said, a waveguide / tweeter system works best with a small dome, or a ring radiator. That's why we used the R2904 for the waveguide stuff in the OSMC speaker (see my signature for links).
do you have an exemple or a graphic bettween a good dispersion with waveguide and wrong matching dispersion without at the low end of a tweeter ? i can figure it out
even on their flagship speakers ATC don't use big wave guides tweeters but a small one with a 25mm soft dome
