In this post we take a look at the Multi-band Compressor introduced to the iLive FX rack in V1.90. If you read my previous post on the DynEQ4 then you will know that soundman Ben Booker has created some presets for the Dynamic FX units and these are now in the library when you install V1.91.

There are two compressor models in the rack:

MultiBD3
The 3-band compressor is geared towards mix mastering, where a shallow 6dB slope is more commonly used giving flat band summing and in phase summation. This provides minimal phase distortion, minimal latency and above all natural sounding transient behavior.

MultiBD4
The 4 band compressor is geared for instrument processing, where the tight slopes are critical for frequency isolation between the 4 spectral bands. Again all slope filters are carefully designed to sum flat. The choice between 6, 18 and 24 dB is a user selectable parameter – the user can decide based on the required band isolation needed for that instrument and compression scenario and also keep phase distortion minimal. So it is possible to have aggressive compression in adjacent bands and still keep phase distortion minimal.

The user can choose the type of ballistics from Peak or RMS, or in auto mode, Opto or Auto Punch.The gain reduction curve shows the actual real world summing of the compressor bands. Some multiband compressors don’t show the real emulated summation.  In some cases audible colouration can be produced if the actual summed frequency response isn’t flat due to the settings of the frequency bands. On our Multiband compressor GUI, the band summation response from the settings is calculated and displayed – you see what you get!

The ‘iLive Rack FX’ pdf download explains the different controls and indicators that are found on the GUI for the MultiBD3&4

You will find some multiband compressor presets created by Ben Booker in the V1.91 library, Ben says “Multiband compressors can fix many problems in the audio world as long as low ratios and little gain reduction are used. They can also sculpt the sound by turning frequency bands up and down individually.”