The tweeter is the most critical part...

[test1223]

@fineMen you are right Blauerts experiment were conducted in an anechoic chamber and the head was fixed. The transfer to stereo in a listening room and a movable head don't hold. You can't pan any sound significantly above or below the stereo plane (no one said this). The effects of equations of the Blauert Band in stereo are different but partly related.

@thewas you are right that the Blauert Bands are so unusual that no natural sound would produce a significant shift only in these bands. Therefore even an unknown sound can correctly been localized in the median plane.

 

[Schollaudio]

(EQed) CDs is as realistic as it gets.....above 12Khz-ish it gets washed though. some few instruments like sharp high-hats sound better on domes

Yes, 1.4 drivers go bad above 10K. Some newer products look promising.

 

[dasdoing]

Yes, 1.4 drivers go bad above 10K. Some newer products look promising.

it seams it can be FIR-corrected. as it is caused by time distorsions due to the phase plug. so DSP speakers can solve the problem

 

[fineMen]

@fineMen you are right ...
@thewas you are right ...

Hm, I always ment that 'rephrasing' (sorry, language barrier) an argument before stating a caveat could help the mutual understanding. Anyway, never mind.

Reiterated, the tweeter's frequency range is always prone to show a mismatch in direct versus indirect sound. By my personal experience as a hobbyist speaker designer, the mismatch from x-over (lobing, jumps) and cabinet edges can become annoying. Some tweeters carry problems in themselves, like an inverted dome of FOCAL fame, some ancient horns, maybe even AMTs the like.

Of course, when changeing the tweeter the design changes, hence a change could help, but not due to the tweeter itself. It would be, in most cases, the wrong focus to accuse the tweeter.

 

[2020]

Very widely different types of tweeters were used

Name Diaphragm Drive Diaphragm Diaphragm Sound pressure
shape principle material expansion [dB]
A.D.A.M planar, magneto- plastic 2,8 x 3,5cm 92
X-type folded static
Expolinear planar magneto- aluminium 4 x 0,5cm 92,5
ARL 90 static
Vifa dome electro- aluminium 2,5cm 90
D25 AG35 dynamic
Vifa ring radiator electro- fabric 2,6 cm 91,5
XT 25 GT 30 dynamic
Expolinear planar magneto- plastic 11.6 x 2.4 cm 100
RT7-Pro static (polyimide)
SEAS dome electro- fabric 2.6 cm 91
Excel T25 dynamic
Eton cone electro- HexaCone 14 cm 87
5-880/25 dynamic (polyaramide)

and FIR filtering was done to EQ them to the same response. If you know a different/better study were such a test was done, please post it, otherwise it is what we have to live with at this time of point until proven otherwise.

I don't want to believe this lol, for if it is true, then the treadmill stops. We only have the ability to envision that something different is better if we think that differences constitute the "why" of it... and we always want better!

A very similar parallel exists in the skincare enthusiast world. Tretinoin is the gold standard of skin anti-aging products (not including invasives like injectables or remodeling peels) given it's potency and proven results, backed up with many studies. HOWEVER, even though this is true, there are a plethora of others that still exist out there: mainly vitamin c (& derivatives), glycolic acid, retinoid-esque compounds (Myristoyl Nonapeptide-3), copper, peptides in general.

I think we WANT for the material and the design to play a large part in the success of a product, because then it gives us a structure to navigate, not something that has been pretty much solved, so "don't plan on seeing any improvements!"

I really want some sexy new speakers with higher resolution tweeters but COVID has destroyed the new, affordable but still luxe, studio monitor segment.

 

[thewas]

I don't want to believe this lol, for if it is true, then the treadmill stops. We only have the ability to envision that something different is better if we think that differences constitute the "why" of it... and we always want better!

A very similar parallel exists in the skincare enthusiast world. Tretinoin is the gold standard of skin anti-aging products (not including invasives like injectables or remodeling peels) given it's potency and proven results, backed up with many studies. HOWEVER, even though this is true, there are a plethora of others that still exist out there: mainly vitamin c (& derivatives), glycolic acid, retinoid-esque compounds (Myristoyl Nonapeptide-3), copper, peptides in general.

I think we WANT for the material and the design to play a large part in the success of a product, because then it gives us a structure to navigate, not something that has been pretty much solved, so "don't plan on seeing any improvements!"

I really want some sexy new speakers with higher resolution tweeters but COVID has destroyed the new, affordable but still luxe, studio monitor segment.

Please beware that the study didn't consider the directivity and distortion patterns which are different with different geometries and materials.

 

[Pearljam5000]

Does anyone know what is an Ionic tweeter?

 

[mhardy6647]

Does anyone know what is an Ionic tweeter?
View attachment 184382

Uses a simple low-ish frequency RF plasma generator and then modulates the plasma with the AF signal.
Plasma tweeters date back to at least the 1950s.

https://products.electrovoice.com/binary/T-3500%20Ionovac%20EDS.pdf

The DuKane/Electrovoice "Ionovac" plasma tweeter.

They are very low sensitivity - thus the horn loading.
They also generate some ozone*, so they should be used in a well ventilated location.

EDIT: You can make yourself one (or two) if you like. Straightforward -- but not quite a trivial task.

Ulrich Haumann's DIY PLASMA TWEETER

Amateur Vintage HiFi Page

www.plasmatweeter.de

____________
* unless this tweeter uses, e.g., helium or other inert gas for the plasma, as did the Hill Plasmatronics loudspeaker of the 1970s.

 

[htnut3]

And there's more plasma tweeter details here https://massless.info/Background.html along with some pages on the history including that Magnat and Acapella and a lot of references too.

 

[Ro808]

Since I‘ve read that thesis and heared how different a speaker sounds just by sloping the fq response by half a db per octave downwards, I don‘t care about tweeter material anymore. Fully agree with that previous statement - it‘s all implementation. Don‘t believe in a specific sound quality/ signature of specific tweeter materials that supposedly can not be reached by other constructions.

It's all implementation, including the signature of specific materials.

For those who don't agree, buy Magico.

 

[fpitas]

Nope it is just you.


I find what I think most important is what is most bothersome to me.

I'm with you. It should be a seamless presentation, without anything catching the ear, unless it was on the recording.

 

[fpitas]

If the loudspeaker doesn't get the midrange right -- to me... it's an epic fail.
So... yeah, another vote for it's just you.
Is this a poll?



(just a little good-natured ribbing -- perhaps even a ribbing about ribbons)

oh, man, I'm on a roll today...
View attachment 182750

EDIT: I've got examples of pretty much every kind of tweeter/treble driver extant here, the one exception being electrodynamic drivers. There are satisfying examples of every genre, even (yes, gasp) cones -- the venerable Peerless 2"AlNiCo drivers were used in some pretty pricey and well-thought-of commercial designs. So, yeah, in all seriousness -- it's nice to have good HF reproduction.

i sort of agree. When I started down the DIY path, the horn was the star of the show, so that got the most attention to detail in the crossover and EQ. But then it became all too apparent the cone drivers needed a lot of TLC to make a good speaker. In the end I may have spent just as much or more time tweaking the cone drivers as the horn. The region around 100Hz actually turned out to be important for voices to sound "right", for example. Pesky speaker design

 

[fineMen]

* unless this tweeter uses, e.g., helium or other inert gas for the plasma, as did the Hill Plasmatronics loudspeaker of the 1970s.

In the 7ties there were just and only analog magnetic tape, copied over and over during the production process, and vinyl records. When back in the day people raved about the plasma it was just hype, and so it is today with new exotic technologies. After the plasma, planar, AMT and other similarly absurd trials to overcome the real limitations of cone drivers for the treble, the dome tweeter was introduced. It won the race with flying colors. A dome of contemporary making could be perfect for just 25$ retail.

Even if the tweeter was outstandingly 'important'--whatever that means again, the case is closed. It includes the waveguide for the dome, it's done. Today's challenge is to overcome hyperbolic attributions to the stereo and 5.1 / 5.1 / 7.2 pp.

 

[mhardy6647]

The DuKane Ionovac plasma horn-loaded tweeter (also sold by Electrovoice) dates back to the 1950s.

Fisher and AR were early adopters of phenolic dome tweeters (e.g., my erstwhile, lovely pair of AR-3)



Bill Hecht developed the (soft) dome tweeter in the 1960s.

Bill Hecht, 1923-2012

William (Bill) Hecht, inventor of the soft dome tweeter (patented in 1967) and founder of United Speaker Systems and Phase Technology, died on September 12, after a brief illness and hospitalization in New York.

www.residentialsystems.com

AMTs seem to be enjoying a great resurgence.

Ecclesiastes 1:9 What has been will be again,
what has been done will be done again;
there is nothing new under the sun.

 

[fineMen]

AMTs seem to be enjoying a great resurgence.

First, the resurrection of the AMT is due to formerly cheap neodymium and the expired patent. It tries to inherit the just and only claimed 'wonder' of the previous attempt to establish the technology. By today's standards the AMT has nothing to offer. This comes clear if You take a closer look. The 'pockets' become more and more shallow and wider; plus the problem of fixing the corrugated membrane to the chassis isn't solved still. Resonances in all directions that generate harmonic distortion especially of otherwise unseen higher order. I've seen HD7 at the same level as HD3 and even the latter wasn't acceptable anymore--with a 'premium' product--in the passband. The invention goes nowhere, too many 'details' to be handled as an aftermath.

The dome tweeter is simple, and it just works. It resembles very much the infamous cable question: people don't accept a part that cannot be problematized. All has to need exceptional care and 'invest', if not to name it a burnt offering (religious), some sacrifice.

Because the public is made to believe that there is an ideal that asks for perfection. Only then the full and hence true experience is achieved. B/s of course, but still, even on this board of ASR propagates of such are not the rarest.

 

[Frank Dernie]

First, the resurrection of the AMT is due to formerly cheap neodymium and the expired patent. It tries to inherit the just and only claimed 'wonder' of the previous attempt to establish the technology. By today's standards the AMT has nothing to offer. This comes clear if You take a closer look. The 'pockets' become more and more shallow and wider; plus the problem of fixing the corrugated membrane to the chassis isn't solved still. Resonances in all directions that generate harmonic distortion especially of otherwise unseen higher order. I've seen HD7 at the same level as HD3 and even the latter wasn't acceptable anymore--with a 'premium' product--in the passband. The invention goes nowhere, too many 'details' to be handled as an aftermath.

The dome tweeter is simple, and it just works. It resembles very much the infamous cable question: people don't accept a part that cannot be problematized. All has to need exceptional care and 'invest', if not to name it a burnt offering (religious), some sacrifice.

Because the public is made to believe that there is an ideal that asks for perfection. Only then the full and hence true experience is achieved. B/s of course, but still, even on this board of ASR propagates of such are not the rarest.

Almost all tweeters radiate modally, ie they are resonating at multiple modal frequencies because multiple resonant modes exist in their passband. Damping is needed to even out frquency response to a geater or lesser degree of success.
There are several dome tweeters which have a high enough first natural frequency for it to be acting as a piston for the entire audio band.
Some are very expensive, but not all.
Berillium is the obvious choice because of its extraordinary specific stiffness. Boron has a high specific stiffness too but pretty well impractical for manufacturing a dome.
Heavily anodising aluminium to produce a thicker than normal ceramic layer can produce a stiff enough dome to be pistonic too.

In reality the damped resonating ones don't sound bad at all

I am mystified by the return of the AMT which has more problems than strengths.

 

[fineMen]

In reality the damped resonating ones don't sound bad at all

Prof. Dr. Goertz, a German published an investigation on the treble branch of loudspeakers. No significant difference was detected between soft, hard domes, AMTcompression drivers. I second him anecdotally. This investigation gives a good hint where to *not* seek for regularly extensively cost intensive optimizations. Dome + waveguide is it.

The real source is this, as was linked by @thewas in a previous post (sorry):

http://www2.users.ak.tu-berlin.de/akgroup/ak_pub/abschlussarbeiten/2010/RotterAndreas_MagA.pdf