The Quintessentially German Loudspeaker of the 70th. Modern Interpretation.

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Here i am measuring the cone tweeter and the SEAS soft dome.
Measurements soon.
 

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Here are the maesurements. The cone tweeters are not very linear and the matching is poor, the second measurement shows. That may be due to age, they have 50 years on their sholders. There is a lot of energy around 10kHz so they sure will sound brilliant.
The SEAS soft dome is 6dB less sensitive on axis. That is not immediately obvious but it has 5 Ohm DC impedance and the cones have 10 Ohm.
The SEAS has of cause a wider radiation pattern and much more energy in the deeper regions. The cones drop of drastically at lower frequencies so the total radiated energy in both tweeter types is not extremely different.
The cones will sound more penetrating though.
 

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I've been using a Monacor HT22-8 cone 92mm cone tweeter in one system shown below lately, Joachim. It is incredibly smooth and mellow sounding. And the price is right! It's VERY cheap. :D

Needs a third order crossover around 3kHz, IMO.

As an aside, the sort of woofer I have come to like lately has a cloth surround and a transparent cloth dustcap (which you can see is almost transparent to reflect the magnet). Very efficient. They don't make them like that much these days, it's rather Tannoy. I suppose a woofer with a phase plug might be almost as good.

An externally hosted image should be here but it was not working when we last tested it.
 

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To heck with authentic, Joachim. I'd go for the nicest sounding. But for all that, the Monacor HT22/8 is not very efficient. :)

I've had this theory for years that soft domes (and spherical dustcaps) are horrible. Robin Marshall discussed it 30 years back:
Robin Marshall: A Modicum of Genius | Stereophile.com

I found confirmation in the String Theory of all things. Lenny Susskind proved that high frequencies behave very badly on a sphere:

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Lecture 9 | String Theory and M-Theory - YouTube

This is a very nice mylar tweeter in my Sony E44's:

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Again, they don't make them like this anymore. A balanced drive cone tweeter. The dome weighs the same as the surround, like that old Audax cheapie. :cool:
 
I know those SEAS 19mm units. The metal one was OK, and the 19TFF is a good celestion HF2000 replacement. These might be a bit expensive, but ring radiators avoid some of the theoretical difficulties by pinning the centre:

An externally hosted image should be here but it was not working when we last tested it.


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It's a toroidal sort of wavefront, not spherical. People seem to like them.
 
OK, that is that interview if hard domes are better then softdomes because soft domes break up in the audible range.
The jury is out on this. I just designed the Kalasan for SB Acoustics that uses a soft dome tweeter, although it is a ring dome.
That construction somewhat shifts the breakup to higher frequencies.
My old company Audio Physic uses cone tweeers.
We started to design those shortly before i left Audio Physic in 2004.
They sure sound different out of many reasons.
 
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