Falling for dome midranges

I have a chance to listen to the vintage American speakers: ADS L980/2. I’m literally impressed them so much especially the midrange sound. They utilize two-inch dome for the midranges. I as a DIY person have a plan if I’m going to use the two-inch domes in my new projects. However, as I listened to them carefully, I found they had unique sound. Well, I have been searching for more info about this driver and I could find some info.

Material: woven soft-dome with proprietary damping
Voice coil: 50mm., wet wound, single layer
Magnet: 1.38 Tesla, 1.1 X 10^-3 Weber
Re: 6 Ohms

From provided info, has anyone ever found any modern drivers that have close specifications to them? Or, in the worst case, no longer find the units with those specifications, could it be possible to special order to nowadays driver manufacturer to make it? Is the data provided sufficient?
 
That 2" dome was developed and build by Braun from the early 70s to about late 80s. It's been successfully crossed as low as 350hz in the higher priced Braun/ADS speakers.
It's very detailed and transparent.
I got it in my Acron 500b speakers that sound fantastic with upgraded caps in the crossover.
Speakers with this dome can be scored on eBay here in Germany for litte money, often under €50 with rotten surrounds of the woofers.

Greets Klaus
 
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Speaker building is always a trade off, even with very boutique Material. I got many different designs (high eff. Coaxial, Fullrange, traditional 3way speakers, studio monitors, omni directional.......
I wish I could combine the strength of all of them.
 
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https://community.classicspeakerpages.net/topic/8246-ads-l980-vs-ar-91/
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Mating a 12" woofer to 2" dome... no wonder it sounded different from other speakers! I can't believe that they used 350Hz acoustic highpass crossover. Looking at the surround of the 2"er, it's Xmax is only couple of milimeters
 
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https://community.classicspeakerpages.net/topic/8246-ads-l980-vs-ar-91/
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Mating a 12" woofer to 2" dome... no wonder it sounded different from other speakers! I can't believe that they used 350Hz acoustic highpass crossover. Looking at the surround of the 2"er, it's Xmax is only couple of milimeters
As I looked at the crossover schematic of the 980s, there was second-order configuration in every section. The high-pass section for the 2” dome is constructed by a 32 uF capacitor and a 2.6 mH inductor. Besides the 980s, there’s a sibling that utilizes this same 2” dome, the L1590/2. The interesting point is that these speakers are equipped with the same “high-pass” filter, a 32 uF and a 2.6 mH. From calculation, this filter combination yields a 550 Hz cut-off frequency; it should be electrical as well. So I believe the 350 Hz acoustic response may be possible when combined with the woofer's response.
 
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^^^^^^ Good luck with that

Take it from a recording/mix engineer……dome mids as a poke through driver are great for making precise mixing decisions……but not much else.…….listen to them for 30 minutes at 95db and you‘ll be reaching for the power button.…..vocals become way to fwd in the mix…..electric guitar odd order distortion cuts like a buzz saw. Wide band operation of a dome mid is much nicer…..but there’s no suitable candidate for this use at volume other than the ATC.…..and at $800 per unit if you can find em?…..not a heck of a lot of performance value there.

But if you’re the guy who likes little colorful bits on a fancy square plate served by pretentious waiters with man buns named Conner or Logan, have at it…….some folks dig the extra clinical……..almost as much fun as a colonoscopy.
 
AudioXpress/VDickason mentioned the SBA/MD60 has 36cm2 area instead of 32cm2 from the data sheet!

Have not checked it but DKM in germany had a 63mm fabric part in the catalogue , could well it is the same part!

And in those times Telefunken had a 66mm(?) dome mid in their speaker line .. must be model TX1000 (or TLX) , square front plate aluminium , large magnet , front grill ... but aluminium voice coil former! I remember this large dome was also offered as a unit from a large company ITT Schaub-Lorenz , included freq resp was very linear up to 7 kHz!

All the old BRAUN domes with that supersticky coating had paper (untreated) carriers for the copper wire , 1-layer winding! The copper insulation melts easily while soldering , not a hi-temp coating! Winding height of the VC was like 6mm pole plate with 8mm coil height! (all from memory) Tight air gap so heat cooling was above average ... the large magnet system (130mm?) had even a ring of stamped mineral wool inside accordingly to an extended data sheet about a speaker building book from Heinz Sahm (cut view of ferrite magnetic system) Dome is not automaticly centered like all other domes from that era!

Tonz of memory ..
 
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