In this free video tutorial, Pro Tools Expert team member Julian Rodgers investigates the differences between the four EQ types available in the native version of the Sonnox Oxford EQ.

What is Q/Gain Dependency?

In an analogue equaliser there tends to be a change in the bandwidth of bell filters as different amounts of gain are applied. In vintage designs there often wasn't direct access to the Q of the filter and this interdependence was simply part of the character of the EQ. Some EQ designs are better regarded in some applications over others because of the way they feel in use and this is, at least in part, due to the Q/gain dependency of the equaliser's design. Control over Q/Gain dependency is a key feature of the Sonnox Oxford EQ and one which differentiates it from the majority of the alternatives out there. 

5 EQ Types In Sonnox EQ

There are 4 EQ Types available in the Native version of the Oxford EQ and a 5th Type is only available for AAX DSP and TDM users. They are:

Type 1 - Minimal Q/Gain Dependency

Type 1 Displays minimal Q/Gain dependency (i.e. the Q doesn't change much as the gain changes). This is a precise style of EQ, similar to an SSL 4000.

Type 2 - Minimal Q/Gain Dependency in boost, constant Q in cut

Type 2 is identical to type 1 in boost but has a constant Q in cut, this makes it ideal for surgical cuts but avoids narrow Q values in boost, which often sound harsh.

Type 3 - Moderate Q/Gain Dependency

Type 3 Moderate Q/Gain dependency means that the Q increases (gets broader) at low settings, this makes the EQ sound more consistent in its behaviour. This type sounds similar to Neve EQs

Type 4 - High Q/Gain Dependency

Type 4 maintains an almost constant area below the EQ curve, meaning that the bandwidth gets much wider at low gain settings. This type of EQ is ideal for mixed material and mastering.

GML Option - AAX DSP and TDM Only

This 5th option has curves which are very accurately matched to the outboard analogue unit.

Watch the Free Video Tutorial for more.

Audio Examples

To illustrate the four Native EQ types in the Sonnox EQ here are examples treating elements from 'Middle Of The Outer Circle" from EAS Studios. All of these examples use the default Q settings.

Type 1 - Aggressive Boost

The relatively narrow Q of type 1 makes boosts which draw attention to themselves, in this example an upper midrange boost at 3.3kHz focusses the bite of this electric guitar.

Type 2 - Surgical Cut

Type 2 has the same charracteristics as type 1 in boost but in cut it is narrower, making the best choice for removing problem frequencies like this whistly harmonic in this piano line.

Type 3 - Musical Boost

Although none of the types are un-musical, type 3 is sympathetic to the material, having a good compromise between selectivity and gentleness. In this vocal example the 5.5kHz boost lifts the top end a little without straying too far into the midrange.

Type 4 - Very Gentle

Type 4's very broad curves will never disrupt the internal balance of material making perfect for complex material like whole mixes. In this case a subtle +1dB boost centred on 600Hz adds some body to the sound. All of these examples use the default Q and while this one does too, I would prefer to narrow this a little as the boost is spread further into the 2K region than I would choose but for the sake of consistency it stays.