I wanted one of the valve fx units after seeing one in action a few times, it has some very smooth distortion, never found one at a good price though...

here is some interesting stuff on the U 87 and some others the site has some interesting stuff on rewiring mics and upgrading components to get a $100-$200 mic to sound like a $2500 mike with about $250 and some time doing the mod, if your into that. I wanted to try to make a ribbon mic but just don't have the time to mess with it.
mic shoot out
Neumann U-87
MXL 990 mod
U47 Copy

Mods for the SCM-960
Microphone PartsMicrophone Parts
The Nady SCM microphones come with a K67-type capsule, which produces a bright, exaggerated high-frequency response that can quickly become tiring on many sources. The mics can be quickly revoiced by swapping the capsule for the RK-47, a Neumann K-47 copy that has a broader, flatter, and lower HF presence peak than the K67, and which naturally presents a more honest, less hyped, mids-forward sound.

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