Below each response picture, there is a note, this one for ER 18 RNX.
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Troels always seems to look out for irregularities around
500Hz in his designs, hence his frequent use of an LCR notch.
That is not the reason he uses lots of filter parts. I have noticed his
newer designs do not include filter parts values. I guess, enough is
enough.
So the response is fairly flat if you stick it on an infinite baffle and listen at a 60deg angle.
At a lesser angle the response still rises by 5dB from 500Hz.
Btw BMS also measure their drivers in a box (11L for the 6S117 & 5S117) without the hash. Although they measure at 100W input rather than 1W.
Last night, I again tried various crossovers with Morel CAT378, through my DSP crossover.
6 db @ various freq, up 9.5K
12db @ at 5k, many other freq.
18db @ various freq.
No matter the crossover, no matter how flat it measure on/off axis, always sounds "nasally congested" or "phasey". Not particularly dynamic either.
I'd say the vintage paper cone tweeter is a LOT better sounding, if rolled off in the highs.
So what else to try that does NOT sound like the Morel?
I like the sound of the paper cone but need more extension.
FAITAL PRO HF105
SB acoustics SB29RDNC-C000-4
ScanSpeak Discovery R2604/8320
6 db @ various freq, up 9.5K
12db @ at 5k, many other freq.
18db @ various freq.
No matter the crossover, no matter how flat it measure on/off axis, always sounds "nasally congested" or "phasey". Not particularly dynamic either.
I'd say the vintage paper cone tweeter is a LOT better sounding, if rolled off in the highs.
So what else to try that does NOT sound like the Morel?
I like the sound of the paper cone but need more extension.
FAITAL PRO HF105
SB acoustics SB29RDNC-C000-4
ScanSpeak Discovery R2604/8320
I am using Audiotools on my iPad with a Dayton calibrated mic.
Dayton Audio iMM-6 Calibrated Measurement Microphone for iPhone iPad Tablet and Android
This gives me the freq. response and the DSP gives me flexible filter settings for crossover and EQ. Both are used to arrive at a starting crossover setting.
However my comment was not regarding of integration between the Morel and my vifa mid. I was just commenting that the Morel CAT378 in general sound not to my liking at all, irregardless of the woofer.
Dayton Audio iMM-6 Calibrated Measurement Microphone for iPhone iPad Tablet and Android
This gives me the freq. response and the DSP gives me flexible filter settings for crossover and EQ. Both are used to arrive at a starting crossover setting.
However my comment was not regarding of integration between the Morel and my vifa mid. I was just commenting that the Morel CAT378 in general sound not to my liking at all, irregardless of the woofer.
How low have you tried crossing it? going up to 9.5K is going to be making the mid the prominent driver... don't rule out the possibility it is the mid that is causing the issue rather than the tweeter. (edit for some reason I didn't see the next post which says irregardless of woofer)..
Also are you dialing in crossover points that take into account the drivers natural rolloffs? ie do the filters you program into the DSP give you a target accoustic slope or are you only looking at electrical slope?
Tony.
Also are you dialing in crossover points that take into account the drivers natural rolloffs? ie do the filters you program into the DSP give you a target accoustic slope or are you only looking at electrical slope?
Tony.
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This measurement suite is not a powerful tool to test speaker
performance. 1/3 rd octave analysis is not enough revealing.
It is practically impossible for the Morel to do what you are
suggesting, not by itself and the way it is built. Morel is not the
issue (nasally congested). I assume you Morel is in good working
order, meaning its impedance and FR is like manufacturer says.
The issue you're experiencing originates somewhere else and
you are not seeing it.
Lojzek,
My Morel (pair) is in good working order.
I don't understand how it is not the issue. I am listening exclusively to different tweeters that I mount on a pedestal. No woofer is involved. Compared to two other soft domes, to a ceramic dome, to a paper cone the Morel sounds clearly unnatural and congested.
Keep in mind that for each tweeter, I set my filters to measure as flat as possible and set high pass in the tweeter's comfortable freq. range.
Have you listened to the Morel CAT378 tweeter?
Are you saying that I am not catching some kind of a sharp peak in the freq response? That would imply that I would have to notch out that sharp peak and that disqualifies from being a good tweeter in the first place.
Am I missing your point?
thanks,
Herman
My Morel (pair) is in good working order.
I don't understand how it is not the issue. I am listening exclusively to different tweeters that I mount on a pedestal. No woofer is involved. Compared to two other soft domes, to a ceramic dome, to a paper cone the Morel sounds clearly unnatural and congested.
Keep in mind that for each tweeter, I set my filters to measure as flat as possible and set high pass in the tweeter's comfortable freq. range.
Have you listened to the Morel CAT378 tweeter?
Are you saying that I am not catching some kind of a sharp peak in the freq response? That would imply that I would have to notch out that sharp peak and that disqualifies from being a good tweeter in the first place.
Am I missing your point?
thanks,
Herman
Consider the Hiquphon OW1 tweeter as used by Linn and others. It is a 3/4" soft dome with waveguide. At about $220/matched pair, not cheap but is one of the best I have heard. Detailed, musical, not fatiguing and just great to listen to. I like cymbals and brushes which most domes smear, these get it right.
Here are some good tweeters: SB TW29R, CSS LD25X, SS Beryllium, KE25SC, TL N26C and the new Transducer Lab Beryllium or magnesium.
Still blaming the driver(s)?
Let me get this right... you put a driver "on a pedestal" (this tells me you are not mounting it in a baffle, right?) and then dial up some crossover before identifying flaws with your ears. How very scientific.
Assuming I am correct in understanding your testing setup, I have to wonder whether you know that using/mounting a tweeter in this way, dangling in space, results in very large frequency response irregularities? These are produced by diffraction of the wavefront by the bezel of the tweeter. For more info, you can read this evaluation by S.Linkwitz:
Diffraction from baffle edges
The shape and size of the bezel determined the diffraction "pattern" of peaks and dips. This is what you are (in my estimation) "hearing".
What you are describing in terms of the sound "tone" that you perceive (tizzy, etc.) is likely a peak around 5-6kHz. If you would just measure the frequency responses on and off axis this would likely become evident to you. You say you have the equipment to make measurements... so why don't you make some and post them here? High frequency measurements, above 1kHz, about about the simplest to perform.
Without good measurements of the amplitude and frequency response of the drivers in your system, you are just flying blind by dialing up some crossover filters that you happen to think will work and then doing "by ear" listening tests. This seems to be your approach. If I am wrong and you are doing careful measurements, please post them.
And finally, STOP measuring in the near field! In the near field your measurements don't include baffle diffraction (the direct sound dominates). When you listen to the tweeter, is your ear right up against the dome? Answer: No. So measure in the far-field. For a far-feld measurement on a tweeter, the mic should be at least 10" (0.25m) away from the dome or at least 3x the baffle width if mounted in a baffle.
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The cat378 is great, dispersion not so great.
With its standard cap 5.6uf cap, it measures flat, down 6db near 2khz, has a bunch more head room than a normal dome (even morel) below 5khz due to the cap electrically rolling the tweet pole just under 4.7khz, and tweet went flattening loud with an 80 watt receiver.
Now the fly in the ointment, look at the manufacturer freq chart, the one showing the cap flattening freq response.
Notice the drooping resonse 30 and 45 degrees off axis.
Forget about sitting a bit off axis like a center channel, maybe 2 people on a couch at 8'.
How do the devores not do this ?
Fine 18' back in 12 x 24 room, but not for wife at far end of couch and me in chair 8' from tv.
Maybe it is me expecting wide dispersion sitting 7'.
My solstice broadcast really wide crossing 2 x 6" near 1,700hz to a dome.
The morel cat378 is Not tizzy, that's the mid cone resonating i bet.
The morel solstice mids are to die for, but remember it is basically an 8" 2 way.
Forget movies, forget riannah, sade, or any music bass driven.
I've want to build a blaster using 4 of the cat378 morels in a vert array, series parallel still 92db.
Like the early thx speakers that seemed to have gone away (multiple tweets, combing, i i know).
Then i remember leveling my 2 x 4" bamboo (5" frames) looking like a derringer, leveling it with pennies.
Maybe 4 tweets would be ok, like the tekton pendragon, maybe not.
With its standard cap 5.6uf cap, it measures flat, down 6db near 2khz, has a bunch more head room than a normal dome (even morel) below 5khz due to the cap electrically rolling the tweet pole just under 4.7khz, and tweet went flattening loud with an 80 watt receiver.
Now the fly in the ointment, look at the manufacturer freq chart, the one showing the cap flattening freq response.
Notice the drooping resonse 30 and 45 degrees off axis.
Forget about sitting a bit off axis like a center channel, maybe 2 people on a couch at 8'.
How do the devores not do this ?
Fine 18' back in 12 x 24 room, but not for wife at far end of couch and me in chair 8' from tv.
Maybe it is me expecting wide dispersion sitting 7'.
My solstice broadcast really wide crossing 2 x 6" near 1,700hz to a dome.
The morel cat378 is Not tizzy, that's the mid cone resonating i bet.
The morel solstice mids are to die for, but remember it is basically an 8" 2 way.
Forget movies, forget riannah, sade, or any music bass driven.
I've want to build a blaster using 4 of the cat378 morels in a vert array, series parallel still 92db.
Like the early thx speakers that seemed to have gone away (multiple tweets, combing, i i know).
Then i remember leveling my 2 x 4" bamboo (5" frames) looking like a derringer, leveling it with pennies.
Maybe 4 tweets would be ok, like the tekton pendragon, maybe not.
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Hello, I'm contributing to a mummified, dried up and dessicated thread by now, but if you can find a set of these to build around then by all means give them a whirl. Production ceased on these in the 1980's sometime but you can find them on the used market. They have a very flat impedance curve, nice low resonance point and the diaphragm is small enough where dispersion will be more than adequate if enjoyed from a usual listening distance. They won't take tonnes of power but so what.
Attachments
maybe this tweeters could be a good choice:
https://sica.it/prodotto/lp-90-28-n92-tw/
https://sica.it/prodotto/lp-110-28-380-tw/
https://sica.it/prodotto/lp-90-28-n92-tw/
https://sica.it/prodotto/lp-110-28-380-tw/
The Audax TW025A28 Ti dome is pretty nice for higher crossover points. Likely the most transparent hard dome I've heard for around $100. Almost having an electrostatic type airy sound, they are very dynamic and open, with a clean extended response and VERY low THD.
As far as the CAT378 concerns, its a fantastic tweeter if you want something that just takes a beating and stays composed, musical and smooth. The downside is poor off axis response. If you mate it with a 87-89 dB/w midbass, you can extend the top end with a R/C shelf ie. using 0.47uf + 3.3R paralleled I series.
As far as the CAT378 concerns, its a fantastic tweeter if you want something that just takes a beating and stays composed, musical and smooth. The downside is poor off axis response. If you mate it with a 87-89 dB/w midbass, you can extend the top end with a R/C shelf ie. using 0.47uf + 3.3R paralleled I series.
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Best Morel tweeter I know is a version from Intertechnik Germany in the same outline than this under
https://www.morelhifi.com/wp-content/uploads/2019/12/ST1308.pdf
but without ferrofluid.
I don't know about the version under
https://www.morelhifi.com/wp-content/uploads/2020/01/CAT378.pdf
because no Thiele Small Parameter (especially Qms) are published (Qms value without ferrofluid much more higher).
Disadvantage of both are too low spl - that means unwanted power compression already at mediocre spl values (like usual of most typical dome tweeters for home audio application).
check out this threads:
https://www.diyaudio.com/community/...ter-without-titanium-and-without-horn.155885/
https://www.diyaudio.com/community/...nklang-phenol-99db-based-to-rcf-tw116.155882/
https://www.diyaudio.com/community/...er-overview-without-ferrofluid-wanted.161577/
please note - there are a lot of dead links - in this case copy the link in this portal:
https://web.archive.org
P.S.: From my impressions hard domes are not harsh in cases of coated metal, kevlar (e. g. Audax TW074, Focal inverted dome T120TDX and T120K).
Except there are no equalizing in the crossover network integrated.
Uncoated metal (titan beryllium etc) and ceramic from my view always harsh and crispy even, if there are equalizer networks integrated.
PS-II: if this driver under
https://www.lautsprechershop.de/pdf/peerless/peerless_ne123w_08.pdf
you mean I would prefer the Hiquphon OW-1 as dome tweeter
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