I have similar experience - I would say more "natural" and closer to the "original". And the T25B goes the next step.
Of course you can build with cheaper components and better ones are significant more expensive. Depends how often do you want to re-build.
I'm often involved in "reference" constructions where the cost of the tweeter ist less important as what you can achieve with it. Nevertheless - the BE crisis and price hack is a huge pain and pity.
Btw you both use active setup for filtering and amping. Did you notice a difference in sound with a protection cap in serie of a strong value in order to avoid DC accidents ?
I have no lost love for domes like diamond or beryllium.
Here's a what an "ordinary" hard dome can do-
NB.
1. the first resonance is 35KHz -> Is there a need for pushing the ultrasonic resonance even higher?
2. H3 and higher harmonics sit around 20dB -> How many rooms are capable for <20dB?
Here's a what an "ordinary" hard dome can do-
NB.
1. the first resonance is 35KHz -> Is there a need for pushing the ultrasonic resonance even higher?
2. H3 and higher harmonics sit around 20dB -> How many rooms are capable for <20dB?
That is correct. It's breakup manifests first as a dip at 25KHz.
Perhaps there's a clever geometry or coating at play, but that is certainly how it is marketed.
(I won't be sending it to a lab to find out what the exact chemical composition)
Perhaps there's a clever geometry or coating at play, but that is certainly how it is marketed.
(I won't be sending it to a lab to find out what the exact chemical composition)
What dome is that? SB Acoustics? That's close to Scan Speak Beryllium performance!
Let's look at some measurements, a little mess but I hope we get the point.
Bliesma T25A vs T25B:
T25B is a league of it's own when you need high membrane resonance (what I needed for a project). Als sensitivity is very high, THD low, off axis better as most 1" (but not as extreme as T25A).
The dip at 40kHz is not from the membrane, it's from the grill and grove around the tweeter. Can be defeated when you are willing to do some changes but as the membrane still needs protection and we probably don't hear it ...
As soon as you introduce a new grid you get new influences. It's hard to beat the original performance (but not impossible ;-))
Scan Speak Beryllium in comparison. I also really like the sound of these.
Something more classical, Visaton KE25SC - also a good and very robust tweeter. This is the old version, I measured newer ones which did not perform the same.
Let's look at some measurements, a little mess but I hope we get the point.
Bliesma T25A vs T25B:
T25B is a league of it's own when you need high membrane resonance (what I needed for a project). Als sensitivity is very high, THD low, off axis better as most 1" (but not as extreme as T25A).
The dip at 40kHz is not from the membrane, it's from the grill and grove around the tweeter. Can be defeated when you are willing to do some changes but as the membrane still needs protection and we probably don't hear it ...
As soon as you introduce a new grid you get new influences. It's hard to beat the original performance (but not impossible ;-))
Scan Speak Beryllium in comparison. I also really like the sound of these.
Something more classical, Visaton KE25SC - also a good and very robust tweeter. This is the old version, I measured newer ones which did not perform the same.
And a different set of measurements and measurement baffle.
T25B with modification:
These dips before the peak are often influences from the frontplate and not the membrane itself.
Compared to ScanSpeak:
And now - some ring radiators:
I REALLY like the sound of these - but dislike their off axis behaviour. And it shows with practical listening when you are not stuck to one chair in your room.
I used a monitor with ring radiator for a few years - when the sound was right close it was dull in the room. When it was good in the room it was way too much up close.
We would need a modern, SMALL ring radiator which can still play down to 2kHz and has enough sensitivity. This could be a great budget option.
T25B with modification:
These dips before the peak are often influences from the frontplate and not the membrane itself.
Compared to ScanSpeak:
And now - some ring radiators:
I REALLY like the sound of these - but dislike their off axis behaviour. And it shows with practical listening when you are not stuck to one chair in your room.
I used a monitor with ring radiator for a few years - when the sound was right close it was dull in the room. When it was good in the room it was way too much up close.
We would need a modern, SMALL ring radiator which can still play down to 2kHz and has enough sensitivity. This could be a great budget option.
22TAF/G is surely a good hybrid fabric/metal 22 mm that should be good in a WG cause the big surround!
Visaton KS 25SC... ? ceramic close to Be enough in clarity ?
Visaton KS 25SC... ? ceramic close to Be enough in clarity ?
If you are in need of a tweeter for scientific purposes, then I can see why one might need pristine ultrasonic response.
For listening to music, a well designed aluminium dome is fine.
Here's another:
Here's another view:
Whether we are concerned about the dip at 29KHz, or the peak at 39KHz, both are far beyond our hearing ability.
And I'm not going to bother with ultrasonic notch filters. As demonstrated by @DcibeL it only bring downs the harmonics that fall at 39KHz, which we cannot hear anyway.
For listening to music, a well designed aluminium dome is fine.
Here's another:
Here's another view:
Whether we are concerned about the dip at 29KHz, or the peak at 39KHz, both are far beyond our hearing ability.
And I'm not going to bother with ultrasonic notch filters. As demonstrated by @DcibeL it only bring downs the harmonics that fall at 39KHz, which we cannot hear anyway.
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Thanks for showing all the informative measurements!
@tktran303 : Might you lift the curtain and tell us which "well designed" aluminum dome tweeter it is? I'm really curious... 🙂
@tktran303 : Might you lift the curtain and tell us which "well designed" aluminum dome tweeter it is? I'm really curious... 🙂
@tktran303 , well, don't get me wrong, my daily tweeter is alumminium, and I have also on shelf among other tweeters the 22 TAF/G which is aluminium and a break up > 25K hz cause the 22 mm dome perhaps. Btw its axis and off axis measure better than some Be. Too bad needs to be crossed a little highish because having no chamber. But 2500 Hz with steep filter is feasible and some cross it over even lower !
Reminder that SEAS released the soft dome version of 27TAC
https://www.seas.no/images/stories/prestige/pdfdatasheet/H1889-06_27TFC_T_Datasheet.pdf
Hope Evgheny will review it.
https://www.seas.no/images/stories/prestige/pdfdatasheet/H1889-06_27TFC_T_Datasheet.pdf
Hope Evgheny will review it.
From a scientifical side of the discussion, I like the 22 TAF/G off axis response too. But to help on the low end to match a bigger midrange, it doesn't really need a WG. But certainly become a very goo tweeter with one. Look at the off axis response here and notice the first break up. https://hificompass.com/en/speakers/measurements/seas/seas-22taf/g-h1283. For I, it measures better than a SB Be. But of course theorical as the SB Be can be crossed over much lower and anywway has not the same exotic dome material.
Btw I purchased a pair because it T&S and specs looks less anemic than a SB26ADC (stronger motor and power handling, though less X-max).
Btw I purchased a pair because it T&S and specs looks less anemic than a SB26ADC (stronger motor and power handling, though less X-max).
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You may change your mind if using NOS DAC about ultrasonic notches on tweeters.
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Joined 2003
Didn't know about that one. Disappointed that it appears to have Ferrofluid, hence the F.
If it's anything like the 27TAC, it should sound great.
Visaton - I just quickly did some listening, no real comparison. The tweeter goes loud and can take quite some power. Better as old Seas but not on Be level. But take it as opinion, this would need a way better comparison.
22TAF/G ... this one started the journey! Used this tweeter in my first reference build with 2 Dayton AL 2". Sounds pretty good in my opinion - but has limitations in max output (small coil). In fact I searched for a tweeter with that sound but more output.
T25B is so good for Waveguides cause it has a SMALL surround! These big surrounds make the membrane appear bigger -> inferior off axis behaviour and bigger starting diameter for the waveguide.
The single F here means fabric. It doesn't have ferrofluid.
TFC = Tweeter, Fabric, Chamber
TAC = Tweeter, Alu, Chamber
The third (and final) example that I will give of an aluminium dome tweeter is below:
Designed by our dear friend @jackocleebrown . Please give the gentleman a slap on the back for clever design, instead of the use of exotic materials that the "high-end-audio" industry would like us to buy.
I would think he knows a little about the importance of geometry, having been award a PhD for his thesis titled
Loudspeaker Compression-Driver Phase-Plug Design
Designed by our dear friend @jackocleebrown . Please give the gentleman a slap on the back for clever design, instead of the use of exotic materials that the "high-end-audio" industry would like us to buy.
I would think he knows a little about the importance of geometry, having been award a PhD for his thesis titled
Loudspeaker Compression-Driver Phase-Plug Design
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