Neumann U87 Transformer - BV-13

[CJ]

big and small, we love em all,

transformers that is, 

twin coils for humbucking, used for the large capsule  FET mic,

 

[CJ]

200 ohms out with series sec,

 

[CJ]

core bracket - just a micro drop of epoxy holding it on,

hi perm lams need to breathe, (magneto-restrictive force)
if you squeeze them tight they can not expand, this causes distortion,

 

[CJ]

yes but what about the frequency?

pretty dang flat for a 10:1,

 

[CJ]

inductance vs frequency,
low levels have to be used because a small Ni core saturates easily,

Henris is Henries in German,  ;D

saturation below 10 Hz at 1 V-ac,

but we can plot other curves,

 

[CJ]

other curves,

 

[CJ]

can't take it apart, Ni perm will be ruined,

so we send it back, came out of a nice mic,

application>

 

[MicDaddy]

Not much help but here's what little info I wrote down