DIY ribbon dipole tweeter, reductio ad minimum

My Ribbon

Hi,
just want to show you how is made similar dipole Ribbon with double magnets and air gap between them. Magnets are little bit different in size 30x10x5 with magnetization through 10mm also custom made. Magnets are not glued but used special device to mount them together.
Ribbon tape is 5micron. custom ordered. Body is made of black anodized 5mm aluminium. Crossover is adjusted at 1500 Hz and minidsp 2x4HD used.
 

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You can see white plastic 1mm between magnets. Membrane is exactly in the middle of this plastic. Difficult to see on photo.

Ok, I understand. Tweeters can be built in many ways!

My picture shows a one-row magnet tweeter with poles pointing to left and right, using the field between. Sounds quite good dispite its looks! The transformer core is from a deceased Quad Els-63.
 

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Can you tell the name of the woofers? The sound in the youtube video is awesome!

I know that judging sound from a video is stupid, but if You have the knack of 40 years of video listening, you can tell if speakers sounds good or not..

Woofer is ceramic driver from SB-acoustics SB17CAC35-4. Ribbon dipole is sounding so good that can't be compared with anything on the market.
 
Were the two ribbons measured with the same sensitivity or did you move the curve of the 11 µm ribbon up. If the response in the 6 dB/oct range is dominated by air mass, the ribbon mass should not matter for sensitivity. Why bother with a lighter foil then, if we are going to eq it flat from a much lower frequency anyway?
The ribbons were measured with the same current driving them. You are correct that the response in the 6db/oct portion of the curve is defined by the air load, so same SPL if the driving current, ribbon area, and magnet + support frame is the same. These measurements were made for the purpose of illustrating this behavior. I agree that choice of foil thickness should involve more than just the usual “lighter is better” mantra.

More details here: Post #23

Just for fun, measurements of 0.65µm ribbon here: Post #122
 
cool design, it used these double magnets with a small space in between them to create a more even and wider fields like the Dahlberg Audio Design one >? believe apogeee used it in there midrange to. its ideal for the type of construction you made with a back plate with magnets and spacer forming sort of one half of the construction. interesting !!
 
You can see magnets in double constructions. Design is flexible and can accept double or single magnets. Foil contacts are not anymore aluminium. Now is made of copper with 100% pure tin plated
 

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