K67 capsule mod for less high end

[LevinGuitar]

Quote from Martin Schneider:

"The [k103] capsule design is a modification of the U87 capsule. It has an average rise of 2...3 dB in the treble between 5kHz and 15kHz (in the lower tolerance range of the published specs)."

https://repforums.prosoundweb.com/index.php?topic=27515.0

From Klaus experiment (same link) about exchanging TLM103 and U87 capsules I guess that their response is quite different (where and how much is the rise in treble of the neumann's k67/87?).

 

[GeorgeToledo]

I am not so sure TLM103 capsule was designed to have flatter response than kk67, because the origin of the TLM103 concept was to make a more affordable version of the TLM171. The TLM171 was a kk67 on a 170. (I’m aware of the later marketing that would often mention U87, but the above is still what happened regardless.)

Maybe they did reign it in some, but I wouldn’t assume it.

 

[LevinGuitar]

I tried my K103 in a C12style 12AY7 and cathode follower 12AT7 circuits and did not like them, too much midrange and not enough highs, but with an Ami M49 circuit (cardioid) is completly different

The donor mic is a MXL V77 with circuit modified into an AMI M49 circuit, K103, 5840 sylvania, Jensen DBE, 1uf siemens MKP. The psu stock voltage is a bit high (158v), that polarize the capsule at 74v, so will lower it to 60v.

 

[Recording Engineer]

That’s how I felt with Samar’s capsule (cardioid-only as the k103) in both the cathode-follower and 49c style, but it was a C37-type direction instead of the C12-type. The low end of Samar’s capsule in the 49c style is phenomenally huge and open. I wonder how the k103 would compare. Following Neumann style, I’d imagine much much more tight.