Many modern users feel frustrated with the original Time Constant provided on the original FAIRCHILD 670 when they cannot adjust the release to match the tempo of the song they are working on, so I have provided a new option which allows new users to fine adjust the release with a variable control.
This option is installed on Position 3 only, which means all other Release positions 1, 2, 4, 5, 6 remain unchanged.

Please specify what release time you are after, I recommend 100 ms to 1 second, which covers most situations.
Here are the original Time Constants :

IMPORTANT :
Please note that the filters allow you less compression at low frequencies, thus allowing no distortion at low frequencies on very fast release settings.