One of the goals in mixing is balancing the volume of individual sounds with each other. Sometimes this can prove difficult when two sounds occupy the same frequency range. This is a common occurrence with bass and kick drums. Many times people will use sidechain compression to lower the volume of the bass when the kick plays.
However, some might find this to be too dramatic of an effect. Instead, you might want to simply lower the volume of specific frequencies that the bass and kick share so that you can still hear the bass playing when the kick hits. In order to do this, you need sidechain EQ instead of compression. In FL Studio, this can be achieved with Fruity Peak Controller.
First, you’ll want to add Peak Controller to your kick drum. Be sure to click Mute at the bottom left corner and then unmute it again to be able to hear the kick playing. Now, load Parametric EQ 2 on your bass track.
Right-click on the low shelf slider and select “Link To Controller.” Alternatively, you can change the low shelf to a low cut or high pass instead. In that case, you’ll want to right-click the Frequency knob instead. Usually, the low shelf will work just fine. You’ll see a window pop up called Remote Control Settings.
Go to the Internal Controller drop-down menu and select “Peak Ctrl – Peak.” The two plugins are now linked together. Right-click low shelf slider again and select Copy Value. Paste that setting onto the Peak Controller’s Base knob by right-clicking and selecting Paste Value on the Base knob. Now when you play the project, you’ll see the low shelf slider moves whenever the kick plays. However, you’ll notice the slider is increasing instead of decreasing, which is the opposite of what you want. Simply turn the Volume knob, located next to the Base knob, to the left in Peak Controller. Now you’ll see those frequencies duck when the kick hits.
Use the bottom FREQ and BW knobs at the bottom right of the EQ to adjust how much of the bass frequency you want to affect. Use the Volume knob in Peak Controller to adjust how much you want to duck those frequencies. The tension and decay knob will adjust the overall speed of the volume ducking.
Overall, you can see this is much more precise when it comes to sidechaining. By only affecting specific frequencies you can keep the two sounds playing together without them clashing with one another. Remember to use your ears and listen for any clashing or mud you want to clear up and adjust from there.