The most noticeable update is the detection engine. Older key detectors needed 2-4 bars of a full mix to give you a reading.
Let’s be honest—old Hornet plugins looked a bit "Windows XP." The updated MK4 features a completely redesigned GUI. It is resizable up to 4K, features a dark-mode spectral overlay, and includes a real-time "piano roll" visualization showing which notes are currently active in your mix. hornet songkey mk4 updated