Hi Simone,
FMOD Studio lacks any way to direct way (i.e. in a single effect) to use a specific frequency band as a sidechain input. However, it is possible to use a combination of a number of effects - Sidechains, EQ, and Sends + Returns or Transceivers - to isolate specific frequencies and use those frequencies as sidechain inputs. In this example, I’m splitting audio into three frequency bands, and using each band to automate a 3-EQ, though you could also use the Multiband EQ for splitting as well as ducking also. I’ve used a Transceiver on my audio track to send an audio signal to three return tracks:
On each of the 3 return tracks, I’ve used a Transceiver to receive the signal, and 3-EQ on each to isolate low, mid, and high bands respectively. After the 3-EQ, I’ve placed a Sidechain that I’ll use to control the level of the corresponding band of a 3-EQ on a different audio track. I’ve also turned the faders down so the signal used for sidechaining isn’t audible. The below image shows the “low” track:
On the audio track I want to dynamically EQ, I’ve placed a 3EQ, and have modulated the band level with their respective sidechain inputs.
Obviously, the setup is a bit convoluted, so I’d recommend trying to keep it simple and use as few frequency bands as possible. It’s also worth pointing out that you’ll have to know the conflicting areas of the spectrum in advance, as there’s no way solely from Studio to dynamically catch peaks across the entire spectrum. Also, If you want to ensure each split band uses the same crossover point as the next band, you can use parameters to automate the crossover point on the EQ of each pair of adjacent band sidechain signals.
This is a bit of an info dump, but I hope it helps!