Measurements and so on.
I have received a number of questions about measurements so here goes.
What you see in this drawing is a magnetostatic woofer and a neodymium tweeter. My own speakers is what's up for measuring and I have added some additional material outside of the ribbon tweeter ( 2x2's ). Today I'm using a little less baffle support on the outside of the ribbon then was used in the measurement (green line). Was the solid black area earlier.
Measuring was done at 70cm on-axis. Level was adjusted for every measurement for increased visibility. One piece of the "baffle" was removed for every measurement too illustrate different baffle support.  No crossover was used during measurement. No "smoothing". Results: Yellow line is the result with all pieces in place. One part is removed from the right side for every measurement. In the last (top) one there is only the magnetic circuit that's present. All parts on the left of the ribbon are present in all measurements (woofer not connected).
Here you can se the shaped magnetic field and where the 26,5mm wide ribbon is placed. The power of the magnetic force field  stays within 0,17-0,21 Tesla where the ribbon is placed. A very nice even result over such a large distance.	click for 1600x1200