Multiband compressors (MBC) seem to incite passionate debates among producers as to whether they are highly useful tools or the spawn of the devil. I have a more pragmatic view, I think of them as tools just like any other tool. The decision to use MBC is reliant solely on the task at hand. You need to ask yourself a simple question: ‘do I need this tool or will another tool do a better job?’
Before we can tackle that question we need to understand what a multiband compress is and how it works.
A multiband compressor (MBC) is a compressor that splits the entire frequency range into smaller bands that can then be compressed individually. Think of it as many compressors working on different frequency ranges and all at the same time. This type of compressor will have all the usual compressor parameters but with one exception: the band crossovers have fixed slopes. This doesn’t help up a great deal when using it on sounds that require an element of fade in/out between bands. However, for processing sounds that have shorter duration and are rich in one specific frequency range fixed slopes are more than adequate. Variable slopes are more useful in most mix related compression processes and we are seeing more and more multiband compressors with variable slopes that can be tailor made to suit the process at hand.
Back to the question at hand.
If the material being processed requires a tool to manage the dynamic range of various frequency bands then a multiband compressor is what you need. A dynamic equaliser will also work and in some cases is a better option as the filter slopes in a dynamic equaliser are variable and not fixed. However, that has now changed with manufacturers providing multiband compressors with variable slopes and a ton of other useful features.
Multiband compressors are still used by mastering engineers to master problematic mixes that require micro editing for specific frequency ranges. They are also very useful when used in the DAW’s groups as they can treat a whole range of frequencies in one simple process -using MBC to treat the drum group is quite a common practice.
In the video I use a rich and dynamic Hip Hop mix to show you how to use FabFilter’s Pro MB multiband compressor to process different frequency bands. I explain how the MBC works and what each parameter does. I end by using different settings to achieve different results and make sure to explain the processes step by step.
Plugin used in this video:
Topics covered in this video are:
- What is Multiband Compression
- Filters and Slopes
- Dynamic Triggering
- Filter Crossovers
- Pros and Cons of MBC
- Timing and Tempo
- Release Value tricks
- Linear versus Minimum Phase
- Smile Curve and relative Responses
- Range and Negative Limiting