Unless a two-way using system an Athos build of this horn offers measurably and audibly better performance, https://josephcrowe.com/products/3d-cad-plans-for-es-290-biradial-horn-horn-no-1670 , a tweeter will be required for use with one of these midrange drivers atop the same horn.
https://www.rcf.it/en/products/product-detail/nd950-2.0#specifications
https://bcspeakers.com/en/products/hf-driver/archive/2/8/DCM50
https://www.bmsspeakers.com/index.php-111.html?id=bms_4591
Troy Crowe typically offers these tweeter/horn combos with arguably improved performance over the stock tweeters,
https://josephcrowe.com/blogs/news/lens-no-1896-for-fostex-t96a?_pos=2&_sid=18decdf41&_ss=r
https://croweaudio.blogspot.com/2020/10/fostex-t925a.html
I can’t locate it now but in one of his midrange/horn combo reviews Troy said that some other tweeters (ribbons? AMTs?) couldn’t “keep up with” the power response, among other performance parameters, of one of these Fostex
“bullet” tweeters when paired with the above midrange drivers.
I couldn’t say either way, though others have discussed and/or may have found pleasing alternatives.
https://www.usspeaker.com/B&C-DE35-1.htm
https://www.diyaudio.com/community/threads/help-pick-a-1-4-compression-driver.391355/
I’m not saying that once a Fostex tweeter’s typically peaky HF response has been flattened without consequence
https://josephcrowe.com/blogs/news/...-for-fostex-t900a?_pos=3&_sid=43fb10bfe&_ss=r
and diffraction issues appropriately tamed with that waveguide, that the T96A or T925A won’t perform admirably.
But would other alternatives work much better?
https://faitalpro.com/en/products/HF_Horns/product_details/index.php?id=903010100
Click on Response Curves at that link. Am I wrong or aren’t these impressive looking horizontal polar charts that these Fostex tweeter can’t show to deliver wide and even HF response?
If so, what kind of driver should I be looking at for this or similar HF horn?
https://www.rcf.it/en/products/product-detail/nd950-2.0#specifications
https://bcspeakers.com/en/products/hf-driver/archive/2/8/DCM50
https://www.bmsspeakers.com/index.php-111.html?id=bms_4591
Troy Crowe typically offers these tweeter/horn combos with arguably improved performance over the stock tweeters,
https://josephcrowe.com/blogs/news/lens-no-1896-for-fostex-t96a?_pos=2&_sid=18decdf41&_ss=r
https://croweaudio.blogspot.com/2020/10/fostex-t925a.html
I can’t locate it now but in one of his midrange/horn combo reviews Troy said that some other tweeters (ribbons? AMTs?) couldn’t “keep up with” the power response, among other performance parameters, of one of these Fostex
“bullet” tweeters when paired with the above midrange drivers.
I couldn’t say either way, though others have discussed and/or may have found pleasing alternatives.
https://www.usspeaker.com/B&C-DE35-1.htm
https://www.diyaudio.com/community/threads/help-pick-a-1-4-compression-driver.391355/
I’m not saying that once a Fostex tweeter’s typically peaky HF response has been flattened without consequence
https://josephcrowe.com/blogs/news/...-for-fostex-t900a?_pos=3&_sid=43fb10bfe&_ss=r
and diffraction issues appropriately tamed with that waveguide, that the T96A or T925A won’t perform admirably.
But would other alternatives work much better?
https://faitalpro.com/en/products/HF_Horns/product_details/index.php?id=903010100
Click on Response Curves at that link. Am I wrong or aren’t these impressive looking horizontal polar charts that these Fostex tweeter can’t show to deliver wide and even HF response?
If so, what kind of driver should I be looking at for this or similar HF horn?
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There are many alternatives with wider dispersion than the B&C DE35 "bullet" tweeter
and more consistent dispersion than the Fostex T900A bullet, with or without Troy's Horn #2258.
What type of pattern do you find better?
Yes, the Faital STH100 horizontal polar response is wider with less HF beaming than the above examples.
The Faital HF107 response looks OK on the STH100:
https://faitalpro.com/press_&_media/news_archive/article/files/VoiceCoil-Jul_13.pdf
A BMS 4550 or 4552 may have a smoother frequency response on that horn, though I don't have an example to post.
What peaky HF response?
Your link shows the opposite.
What is shown in the link is the T900A's low end being difficult to manage.
Look at it's stated resonance frequency, and see where that overlaps with the 'peaky response', look at the CSD and you will see a correlation..
Have you seen how a transducer with high Q look on the bottom end before the 'knee?
Do you remember what was explained concerning a transducers mass breakpoint.
https://faitalpro.com/en/products/HF_Drivers/product_details/index.php?id=502010095
https://www.beyma.com/en/products/c/compression-tweeter/1TWCP228/twt-cp-22-8-oh/
https://www.beyma.com/en/products/c/compression-tweeter/1CP21F8/twt-cp-21-f-8-oh/
https://www.ciare.com/en/products/tweeter/1.75/8/CT441
https://celestion.com/product/cdx1-1425/
https://www.visaton.de/en/products/drivers/horn-tweeters/tl-16-h-8-ohm
JBL has a whole selection of tweeters in the 045 Ti/mg/Be, and the UT-xxx line. Just not available for regular purchase.
If you can have a horn/wg to fit, the little D2415K does well as a tweeter in different current productions from 2k+ and up.
There is also the old 2405/077 etc. line.
Tannoy had a whole line of tweeters named : ST-xxxx. But primarily domes i believe.
Yamaha had a line of tweeters with duralumin and cvd Be diaphragms.
Reintroduced in 2023, just expensive.
https://www.proaudiodesign.com/products/tad-et-703a
Else there is a whole alphabet of vintage/special/exotic Japanese compression tweeters with eyewatering prices.
Of those two, I would say neither, though the T900 tweeter with the horn shows a more consistent dispersion from from 10 to 20kHz. The patterns of the Faital HF10Ak/STH100 combo look a lot better; wider and more consistent dispersion.
You're saying that this 5.7kHz resonant "dip" is caused when the tweeter's impedance hits ~ 9 ohms? https://cdn.shopify.com/s/files/1/0...ot_2023-10-09_172720_480x480.png?v=1696887126
Yes, Troy's filter looks like it makes a very substantial CSD improvement
https://cdn.shopify.com/s/files/1/0...ot_2023-10-09_194730_480x480.png?v=1696895344
And Troy had earlier measured very low H3 and IM distortion on the T900.
https://josephcrowe.com/blogs/news/fostex-t900a
If only his horn could give way less beamy directivity, like the Faital HF10Ak/STH100, but that's no doubt much more due to the T900. https://josephcrowe.com/blogs/news/fostex-t900a-with-horn-lens-no-2258
I wish Troy would have found a tweeter/horn combo with directivity to better match the ES290/DCM50 directivity.
CAUTION! I am NOW at the end of the April deadline, and I must decide to either go with Troy’s 3-way or end up with nothing.
So, I need tweeters available as a pair, which are in sonically intact condition, that are as quick and distortion free as the Fostex T900 but are no where near as beamy and not at TAD prices. Please help ASAP.
Would the Faital HF10Ak/STH100 be the best on all counts? Tweeter budget ~ $2k/pair.
What makes you end up choosing this one? It's a good comp driver if you want to cross low to a 12" or similar. 1 exit compression driver, ti diaphragm, a little challenging to filter 1,5-2k due to the 'hole' you usially see. Might disappear" with some resistive loading like the good old TD-2001. CSD is far from as clean as some drivers, but many enjoy the Ti resonant artifacts in the top end.
If you want a well behaved Ti diaphragm, 1" i'd rather take a hard look at the 18S ND1090, 1095N or Nd1tp (mr. Crowe did not like it approve of it, but neither did he try to adjust the diaphragms which are very sensitive).
5530ND from BMS is a nice driver.
ND360 B&C also would do good as a tweeter, does not like itself much below 2k.
Old reliable JBL 2405/077 ring radiators aluminum diaphragm's. Lot's of them around, relatively inexpensive. Does narrow up vertically for a wide/wide bi-radial CD you can use 2404. May be an issue getting original JBL replacement diaphragm's. Plenty around to find a pair for a listen.
You can always try something else down the line and just flip the drivers if you find something you like better.
Rob 🙂
https://www.audioheritage.org/vbulletin/showthread.php?23869-075-2402-076-2403-2404-077-2405
You can always try something else down the line and just flip the drivers if you find something you like better.
Rob 🙂
https://www.audioheritage.org/vbulletin/showthread.php?23869-075-2402-076-2403-2404-077-2405
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You are correct.
And here is a measurement of the proposed combo STH100/HF10AK
https://www.dibirama.it/component/c...-1-73-8-ohm-120-wmax.html?catid=22&Itemid=580
Kevinkr is or was using it last year above his TAD TD4001/A290 combo. https://www.diyaudio.com/community/threads/26-pre-amp.151421/post-7831685
So, doesn't the Faital HF10AK qualify as a tweeter? Again, its polar charts show it has much wider directivity than the T900, or any of the Fostex "bullet" tweeters. Otherwise, according to Troy's H3 and IM distortion measurements and when adding his filter circuit the T900 evidently performs very well.
Of course, I'd still prefer a tweeter that didn't require such corrective filtering, and one that wasn't as beamy as the T900.
Any other fast, low distortion and wide dispersion tweeters and/or tweeter/horn combos to recommend above the DCM50 midrange?
Silly question? As Troy Crowe seems to have gotten the bugs out of the T900, might there be a compatible CD horn for it the T96 and/or other Fostex bullet tweeters?
Hi oltos,
A word of caution, IME those super tweets, as they typically are mounted far from the ideal distance from the CD /horn center, will only blend pretty far away from the speakers and then only where X marks the spot.
A word of caution, IME those super tweets, as they typically are mounted far from the ideal distance from the CD /horn center, will only blend pretty far away from the speakers and then only where X marks the spot.
Point well taken, but my builder Troy Crowe seems to have adequately aligned the centers of tweeter and midrange drivers to ensure coherent sound.
https://josephcrowe.com/blogs/news/bms-4591-with-horn-no-1670?_pos=9&_sid=eb9a0854d&_ss=r
No.1670 features a rear plinth to mount the high frequency horn. The plinth extends far back enough to allow physical time alignment between the HF and MF drivers. This is a critical design element in terms of successful integration of the two drivers. If the high frequency driver is left too far forward, then it will be perceived as a distinctly different sound source. In other words, the sound will not be cohesive or coherent between the midrange and treble.
Since you are at someone else’s mercy I think you should defer to their methodology. Diyaudio is full of quirky individualist chasing their own personal dragon; Mixing and matching these disparate approaches may end of being the most satisfying solution for you or the least satisfying.
Good luck and above all have fun and enjoy the music!
Good luck and above all have fun and enjoy the music!
Yes, that i very easily remedied. Keeping the vertical distance small enough at these high frequencies to avoid lobing is another matter altogether.
Say you’re crossing over at 5kHz, ideally I’d keep the vertical distance between driver centers to ~4,5cm - or the combined waveform from the two drivers, what you are going to hear, is not going to resemble anything like the posted waveforms from the separate driver/horns.
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I think this is excellent advice that should be heeded. Trying to piece together a speaker based on subjective comments you've read online, especially with a desperate sense of urgency, may not work out as well as you hope. Troy appears to have experience with plenty of tweeters and I would lean heavily on his experience. Tell him to sound you're looking for (as I'm sure you have) and he should be able to come up with a good combo.
Less than 2" distance between the vertical centers of the HF and MF drivers? I don't think even in Superlian's design achieved that.
https://www.diyaudio.com/community/threads/best-compression-drivers-today-2022.382609/post-7365476
How many three-way designs have?
I much tend to agree but I also agree with what both of you are implying. That's why I really wish that I could find a two-way solution. I will also discuss that option with Troy this week.
But would a main difference between an exponential and constant directivity horn be that they deliver detailed and spacious sound, respectively? If so, what horn might offer the best of both?
No, a main difference would be in the horn's respective coverage patterns.
The difference between "detailed" and "spacious" sound would be a property of your perception of the program material in the room you listen to them in.
Your AH425 might be, definitely worth giving them a listen.
Have you discussed the option of using your horns and drivers with Troy?
The main difference is power response. A CD type horn depending of the pattern will either not show HF roll off or less HF roll off. This can make them sound bright depending on the room. The bottom line is you have more HF energy in the room and more even coverage. Look at the DI curves if you can find any published.
Don't worry all that much about ended up with a 3 way. Using passive crossover the best you can do is get the drivers time coherent where they are below BL curve and get them to integrate the best you can. There will be comb filtering at any given point in space and although it can make for a nasty graph it doesn't seem to be all that audible.
Rob 🙂
Resolving this issue gets very complex and it seems easy to be led astray, unintentionally, of course, by these very experienced members. https://www.diyaudio.com/community/threads/loudspeaker-perception.130352/page-3#post-1618009
But if a consensus were based on the commentary on that page it would seem to support your statement. That said, would I still prefer a horn with a wider coverage pattern; that is, one with this kind of directivity?
https://sphericalhorns.net/2022/09/20/acoustic-loading-optimized-william-neile-horns-part-2/
Docali said his horns won't be available until next year, so clearly not an option. But how much would my room pose problems with utilizing horns with these patterns?
https://sphericalhorns.net/wp-content/uploads/2022/09/wn300alo_radpol_hrz.jpg
https://sphericalhorns.net/wp-content/uploads/2022/09/wn300alo_radpol_vrt.jpg
Since I've had no chance to hear the AH425s, nor did Troy give any indication that he did either, last month I asked Troy as follows:
Male and female vocals on Glen’s system were very natural and effortless. Imaging seemed generally accurate. Again, room acoustics plus my somewhat tired and anxious condition may have colored my perception of sound stage size, but I wonder have much that of the ES450 horn and Fostex tweeter/lens combo differed from this.
https://josephcrowe.com/blogs/news/circular-horn-no-1689?_pos=1&_sid=17f3ec02b&_ss=r
https://cdn.shopify.com/s/files/1/0..._filled_contour_plot_480x480.png?v=1656097530
https://cdn.shopify.com/s/files/1/0...ot_2023-10-14_170306_480x480.png?v=1697317415
As an opportunity to hear a system with the # 1689 horns is quite improbable, please try to provide a general subjective listening comparison of the ES450/B&C DCM50/Fostex T96A and the 1689 horn either with the RCF ND350 used in your review or the whichever driver you think would best compete with Glen’s Midrange/HF combo.
To that, Troy instead first asked for that sketch of my room. Then he proposed:
Hi Gregory, I've recently received an order to custom design a 2-way using the Altec 416-8B with the ES-600 Biradial and newly developed SB Audience 75CDN-T.
My thinking is that the Altec will do well with a first order crossover at 1.2kHz since it is so well behaved in the midrange. First order will result in great soundstage depth as well as keeping the overall subjective sound have zero harshness. I am particularly sensitive in the 1-2kHz region and I cannot tolerate any harshness.
I wanted to reach out to you and see if this would be of interest to you for your project.
Here's info on that horn: https://josephcrowe.com/products/es-600-bi-radial-wood-horn-no-1978
Not like Docali's horn and no specified driver, but how would you evaluate it?
https://cdn.shopify.com/s/files/1/0142/2848/8292/files/polar902_480x480.jpg?v=1602552211
In any case, when I reply to Troy I would have to include this quote from Pierre as follows
A 15 inch mid woofer beams in the midrange, and crossing lower in frequency gives more work to the compression driver-horn that radiates more broadly. 700-750 Hz is the accepted upper limit for a 15 inch midwoofer. The TH4001 was sized with this in mind, (fc 320Hz). Many plots show low excursion to 350 Hz.
Wisdom is to choose xover freq one octave above the horn fc. This prevents exposing the driver to low frequencies below the horn loading Fc. Perfect fit.
The ES600 looks like a sound design but it is a smaller horn as advertised and measured: fc 600 Hz. There is not much margin for crossing at 700-750 Hz. This would concern me, and I would at least recommend a larger horn (ES450?) if staying with this design.
Measurements show the horizontal dispersion of the TH4001 extending higher in frequency than that of the ES600. This is by virtue of the fins. The difference is more noticeable above 10kHz and thus more important in a Two way design than in a Three way. If you want to try listening off axis without a tweeter, you want the fins/cells. In any case, the ES600 is an improvement over the round AH425 from this standpoint, but finned and multi cell horns rule.
Bottom line is I haven’t heard both so who knows, really…. But I would lean towards the TH4001 for your application, and towards the ES600 for a more compact three way that has a smaller midwoofer.
Assuming you agree with Pierre's assessment, it looks like the ES450, ES290 one of NicoB's https://audiohorn.net/next-gen-bi-radial-horn/
https://audiohorn.net/x-shape-horn/ or which other (CD?) horn?