Schematic for Neumann TLM103

Hi folks:

Anybody got a schemo for the TLM103, or know where one lives that's viewable? There's an interesting discussion going on at rec.audio.pro about why the TLM103 is sensitive to what mic pre you use, more so than most transformerless mics. I'm wondering if there's some kind of weird inductive stuff in the output, maybe to block RFI.

Peace,
Paul

Dale had posted what might be a gain stage fragment of the circuit in the past at the lab.

I think I what might be going on but I am not going to share in public.

I don't think it is the microphone.

Can you post the link.

Neumann puts a little network on the output of all the mikes that use internal DC/DC converters undoubtedly to block hash from being radiated by the microphone, particularly in the case of the TLM103 with the square wave converter that it uses to generate the polarizing voltage. The network is probably something like a 47 uHy choke followed by a 2200pf cap to ground on each output leg. This is not going to affect the downstream preamp.

A more likely cause for the difference would be the way in which the single ended capsule output is converted to the balance send on the cable. Think lack of a phase splitter. Kind of like some more blueish mikes.