Hello! Welcome back.
In our last lesson, we took a big step in mastering by using EQ to sculpt the overall tonal balance of your track. We cleaned up mud, added weight, and introduced air, all with subtle, broad adjustments. You learned that mastering is about polishing, not re-inventing.
Now, we'll address the second major component of a master: dynamics. A mix might have a kick drum that occasionally pokes out too much, or a cymbal crash that's a bit too sharp, but the rest of the track is perfectly balanced. If we used a standard compressor, the loud kick would trigger compression on the entire song, dulling the vocals and guitars unnecessarily.
This is where multiband compression comes in. Today, you will learn to use a multiband compressor to control dynamics across different frequency ranges. This powerful tool is like having several compressors in one, allowing you to tame the low-end boom without affecting the high-end sparkle, giving you precise dynamic control over your master.
1. From One Compressor to Many: What is Multiband Compression?
A standard compressor acts on the entire frequency spectrum. A multiband compressor first splits the audio into separate frequency bands—typically Low, Mid, and High—and then gives you an independent compressor for each one.
This means you can apply heavy compression to the bass to make it tight and consistent, gentle compression to the mids to control vocals, and no compression at all to the highs to keep them open and airy.
In FL Studio, your go-to tool for this is the Fruity Multiband Compressor.
The key difference between this and a regular compressor is the ability to choose which frequencies each compressor acts on.
How to use Fruity Multi-band Compressor // Mixing in FL Studio
To see this distinction explained in the context of FL Studio, watch the beginning of this video from XDizzle.
Watch the first minute and a half (00:00 - 01:37). The creator clearly explains why you'd choose a multiband compressor over a standard one, specifically for solving problems like muddiness without needing to reach for another EQ.
2. Understanding the Controls
The beauty of the Fruity Multiband Compressor is that you already understand most of its controls. Each band has a Threshold, Ratio, Attack, Release, Knee, and Gain knob, which function exactly as they do on the compressors you've used before.
The new and most important controls are those that define the frequency bands themselves. These are called crossover frequencies.
Fruity Multiband Compressor - Effect Plugin
The official Image-Line manual provides a definitive guide to every knob on this plugin. It's the best place to get a clear, technical understanding of the controls before you start using them.
Please read two key sections from the manual: Start at the 'Input & Filtering' section and read down to the 'IMPORTANT NOTE' about the filter cutoffs. This explains how to set the crossover frequencies that separate the bands. Next, read the 'Low, Mid & High Band Compressors' section. This will confirm how the familiar compressor controls (Threshold, Ratio, etc.) work for each band. Focus on understanding what the four 'Filter cutoff' knobs do. These are the heart of the multiband setup.
As the manual explains, the four knobs below the display set the boundaries. A great feature of this plugin is the ability to solo or mute each band, so you can hear exactly what you're working on.
Let's see this in action.
How to use Fruity Multi-band Compressor // Mixing in FL Studio
Returning to the XDizzle video, watch how he manipulates the compressor controls for each band and, crucially, how he solos them to make precise adjustments.
Watch these two segments: Controls in Action (01:37 - 03:40): See how lowering the threshold activates the compressor (indicated by the red line) and how the basic controls work within a single band. Soloing Bands (06:09 - 07:33): This is a critical skill. Pay close attention to how he solos the low, mid, and high bands to fine-tune the crossovers and hear the effect of the compression on just that part of the spectrum.
3. A Practical Mastering Workflow
Now that you know the tool, let's establish a strategy. In mastering, the goal is control and transparency, not aggressive sound-shaping. A good starting point is to apply the most control to the low end, be gentle with the mids, and be very subtle with the highs.
Advanced Tips for Mixing & Mastering in FL Studio
The article 'Advanced Tips for Mixing & Mastering in FL Studio' gives a concise, high-level strategy for this.
Read the section titled '1) Multiband Compression'. Focus on the general strategy described: 'harder compression to the lower bands, slightly less compression to the mid band, and subtle (if at all) compression on the high end'.
Here is a step-by-step workflow based on that strategy:
Step 1: Set Your Crossover Points
- Use the solo buttons for each band to listen.
- Low/Mid Crossover: Adjust this so the Low band contains your kick and sub-bass, but not much more. A starting point is often between 120 Hz and 200 Hz.
- Mid/High Crossover: Adjust this so the High band contains the "air" and "sizzle" of cymbals and synths, but not the main body of vocals or snares. A good starting point is between 3 kHz and 5 kHz.
Step 2: Control the Low End
- Goal: To tighten the kick and bass, controlling any "boomy" notes and creating a solid, consistent foundation.
- Settings:
- Set the Threshold so you're getting 2-4 dB of gain reduction on the loudest bass notes.
- Use a moderate Ratio, around 2:1 to 3:1.
- Start with a relatively fast Attack (10-30ms) and a medium Release (50-100ms) that's timed to the rhythm of the track.
Step 3: Gently Tame the Mids
- Goal: To catch any harshness from snares or overly loud vocal phrases without squashing the life out of the mix.
- Settings:
- Be subtle. Set the Threshold so you're only getting 1-2 dB of gain reduction on the loudest peaks.
- Use a very low Ratio, like 1.5:1.
- This band is where you want to be most transparent.
Step 4: Polish the Highs
- Goal: To smooth out piercing cymbals or sibilance (harsh 'S' sounds) without making the track sound dull.
- Settings:
- Often, this band needs no compression. If you do use it, be extremely gentle.
- Set a very high Threshold so that only the absolute sharpest peaks are being compressed. A fast attack and release can work well here, acting almost like a de-esser.
- A Ratio of 2:1 is a good starting point.
To help you refine your attack and release settings, let's watch one more short video that explains the sonic character these controls impart.
How to MultiBand Compress Your Master
This video from Sage Audio provides excellent, concise explanations of how different settings affect the sound. We'll focus on downward compression and the timing controls.
Watch two key clips: Downward Compression (00:37 - 01:18): This reinforces the core concept of what you'll be doing: reducing the level of signals that cross the threshold. Attack and Release (03:52 - 04:36): This explains how a short attack and long release creates a smooth sound, which is often desirable in mastering, while the opposite increases clarity.
Test your understanding!
You're mastering a track and the kick drum is inconsistent. Some hits are powerful, but others are weak, making the low end feel uneven. However, the synths and vocals in the mid-range are perfectly dynamic and expressive.
If you apply a standard compressor to the whole track, it tightens up the kick but also flattens the vocals, removing their energy. How would you use the Fruity Multiband Compressor to solve this problem?
Show answer
- First, you would load the Fruity Multiband Compressor and use the solo buttons to set your Low/Mid crossover frequency (e.g., around 150 Hz) so that the kick drum is almost entirely within the Low Band.
- Next, you would apply compression only to the Low Band. You'd set the threshold to catch the loudest kick hits and use a moderate ratio (e.g., 3:1) to reduce their level, making the kick's dynamics more consistent.
- You would leave the Mid Band and High Band compressors bypassed or with their thresholds at 0 dB, so they are not affecting the vocals and synths. This way, you fix the problem in the low end without damaging the dynamics of the rest of the track.
Conclusion
Multiband compression is one of the most powerful tools in mastering. By treating different parts of the frequency spectrum independently, you can solve dynamic problems with surgical precision, achieving a mix that is both controlled and vibrant.
Key Takeaways:
- Divide and Conquer: Multiband compression splits your audio into frequency bands (low, mid, high) and gives you a separate compressor for each.
- Set Crossovers First: Use the solo buttons to listen and set your crossover frequencies to isolate different elements of your mix.
- A Common Strategy: Apply focused compression to the low end to create a tight foundation, use very gentle compression on the mids to control peaks, and touch the high end lightly, if at all.
- Transparency is Key: In mastering, use low ratios and aim for only a few decibels of gain reduction. The changes should be felt more than heard.
Preview of Next Lesson:
We have now addressed our track's tonal balance with EQ and its dynamic consistency with multiband compression. The final step before we export is bringing the track to a competitive volume for release. In our next lesson, we will explore loudness metering (LUFS) and learn how to analyze and set the final loudness of a track to meet targets for streaming platforms.