DIY Ribbon Headphones

My transformer is wound on a ferrite ring core measuring 20 * 12 * 6. It has a primary winding of 800 turns of wire 0.12. The winding is wound with sectioning, it has 8 sections of 100 turns. The DC resistance is 32 ohms. The secondary winding is wound with a stranded wire consisting of many thin wires to obtain a cross section of about 2 square millimeters. It is possible to use a wire as on the primary winding, all wiring is soldered together at the ends. The secondary winding has 8 turns.
 
The trafo isn't necessary to feed near-zero ohm driver. And actually, when I tried a ribbon mic in the reversal manner(without trafo) it worked surprisingly well as a tweeter. Only as a tweeter, because its small membrane area and I see no way to make it sealed as well(I mean front chamber has to be sealed from rear one, as a planar and static types of headphones does) so you'll never get a deep bass with it. However, I see no one pictures of this thread and can not be 100% sure if I'm right.
 
PS: I've simulated ferrite ring trafo 20x12x6mm 800/1 (24m of .12mm wire) with an ideal winding coupling(real one <1 will make things even worse), and found that such trafo isn't able to work with a moderate input voltage 2VRMS and frequencies <50Hz. See attached 20Hz is very distorted. In fact, ferrite is the worst core material for such application, the best one probably nanocrystalline or, as I said above, direct drive without any trafo.
 

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The trafo isn't necessary to feed near-zero ohm driver. And actually, when I tried a ribbon mic in the reversal manner(without trafo) it worked surprisingly well as a tweeter. Only as a tweeter, because its small membrane area and I see no way to make it sealed as well(I mean front chamber has to be sealed from rear one, as a planar and static types of headphones does) so you'll never get a deep bass with it. However, I see no one pictures of this thread and can not be 100% sure if I'm right.

In fact, the bass of this driver is just like no other, even despite the imperfection of the transformer. It is deep and very fast. You literally feel the seismic pressure right into the brain.

DSCN1182_encoded.avi - Google Drive
 
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7SVG, oh yes, I saw the same thing when I turned reversal(i.e. as a speaker) my handmake ribbon mic, and from your video, I heard the transducer response more like a tweeter i.e. no bass. The major problem is such plain transducer isn't sealed(front vs rear chambers of cap), so it is an acoustical issue. Hard to say how low the limit of bass you've got but I think it is 40-50Hz, and probably some additional whistle-turbulence at 20-40Hz. Actually, you can try to move to a planar scheme but with the same "single turn" aluminum membrane instead of mylar membrane with thin aluminum plated 100 turns coil. I see no another way make sealed front/rear chamber.
PS: if you'll keep the maximal ratio of membrane area to leakage area(much higher than I see in your video yet, where, as I guess about 5-10% of air leakage), your frequency response could be deeper in basses. But what about whistles?
 
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You strongly mistaken when you say that the bass is not, the shooting was conducted by a cheap camera, the microphone on which side, these drivers have a sharp focus, and their application implies the proximity of the membrane to the ear, and besides there is no ambushshur. The transformer can be improved by using heartwrappers with a higher magnetic permeability. I also know that an amplifier capable of operating at such low load resistance (current output) is possible. And there are no whistles, you did not listen to them live.