FAC Transient
"An outstanding dynamics processor providing precise design and control of the attack and sustain stages of your instrument. Transient designers or shapers are often associated with drum enhancements . . ." from the App Store description.
App type: App and AUv3
App store link: 
FAC Transient
Developer: Frederic Corvest
Developer AB Forum Handle: @FredAntonCorvest
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