Golden Age Project FC3 Mods
The GAP FC3 combines a linear circuit with a peaky 32mm K67 capsule type. The result is a not flattering to most sources, creating sibilance on vocals and fatigue on most everything else.
The stock GAP capsule is a typical 32mm K67 type, found in just about every inexpensive large-diaphragm condenser microphone on the market. It has a peaky and uneven response that is not very musical, and tends to require EQ to fit into a mix.
We recommend replacing it with a K47 type, which will give a more neutral top-end response, with rich midrange detail. Our favorite capsule for this mic (assuming the stock circuit is retained) is the RK-47.
Another option is our RK-12. The voicing of this capsule is bright, but it sounds different than the stock GAP capsule; it has a smoother top-end response and warmer lows. It excels for female vocals.