When I tried the TLM103 years ago in the Musicstore, then I had a certain feeling as if treble was overemphasized, I was not satisfied with the sound.
The ratings for this microphon at Thomann are partially also not so good:
"... put into operation, I was sobered - does not sound so great ... Well, first gather experience, I thought! After about a year of work in the studio I was then really dissatisfied ... nothing I recorded with the mic was better in my songs - on the contrary - in the vocal recordings I was only busy with post-processing, so cold and sibilant sounds the TLM 103! Then I've dealt in more detail with the Mic on the net, and see there a lot of criticism in the professional - forums ... Tenor: not suitable for vocals at all! So I feel it now also, although it is purchased by most yes mainly for this. I think that many buy this Neumann, because they can not afford another, and then hear it beautifully - I sold it again! ..."
> i am doing live streaming and my room is fully coverd in Akustik foam and everything
Difficult to say, whether this has been done properly and that now the room is sounding well for recording...
Some rooms that people use for recording are sometimes even too low so that the acoustic is not well.
Its difficult to clarify this through a forum without any sound material, without knowing the room and the acoustic.
It also doesn't sound to me to be a RME specific problem. You can try to use the EQ and compressor to modify the sound a bit according to your taste.
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