[abbey road d enfer]

Is it a two bobbin transformer, or a small EI? In the last case I have very hard time understanding how they managed to squize those specs.

I don't know, I've not opened it. It's in a rather large (40mm diameter) shield, so it could be a larger core than usual.

The magnets in those mics are Neodymiums and should give about 35000Gauss (0.35T). The only way for Nd to lose magnetics is to heat it. I highly doubt the mic would withstand it without showing the traces... unless they installed them this way.

The magnets are about 50mm long, about 4mm square section, seem to be glued on the vaguely elliptic steel frame. I have Nd magnets 15mm diameter 3mm thick that have considerably more pull than those in the mic.

You say it gives very low output, do you have some other ribbons to compare to?

At the moment, the only ribbon I could compare it to is an M160 (the other is an active Sigma). The Rb500 seems weak in comparison. Next week, I'll have the new AT ribbon mics, a Royer 121, a Melodium RM6, I'll do comparisons.

Obviously, something going on there. If you get stuck with this mic, would you mind sending it here for me to check it? You really picked my interest with this one!

I'm due to go to New York next month, I could ship them from there.

[Rossi]

Given the resistance values, I suspect it is the exact same transformer I described in the other thread (there was a picture: single bobbin, relatively small).

You should get much more level than from your M160. Maybe something is wrong with your magnets. Could it be that one of the magnets is reversed?

The new AT4080 ribbon is  quite nice, btw.

If you have a booth at the Frankfurt Musikmesse, I could drop by and pass it off as work. 

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