Solid State Logic X-EQ manual Non- Linear Phase EQ

Models: X-EQ

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4.4 Non- Linear Phase EQ

filters a s precise and clean as pos sible. For control led generation of distortions we recommend using enhancers or any other specialised processors wi th proper built-in anti - aliasing technology.

4.4 Non- Linear Phase EQ

Phase shift in equ ipment is probably one of t he m ost misunderstood topics in audio. Phase shifts often get blamed for anything that is not classed as typical distortion. The reality is that all analogue EQs produce a deviation from linear phase which is specifically related to the shape of the EQ curve, and it is precisely these phase changes which produce the required gain reductions. This is a very natura l process which can be found in th e aud io characteri stics of room s, materials and elsewhere.

Though it is not possible for us to detect phase in isola tion, the phase shift of an EQ can often be the cause of the ‘magical’ sound of that device once the EQ’d signal is added back into the mix. For example, the Duende channel EQ derived from the SSL analogue consoles – plenty of phase shift and plenty of magic!

In contrast, a li near-phase EQ delays all frequencies by t he same amount. This can only be achieved in the digital domain by using s pecial techniques. Whi le t his process i s ve ry

effective in certain s ituations ( eg. ‘surgically’ r emoving troublesome frequencies), it should not be considered as a superior tool for the majority of EQ tasks.

Linear phase e qualisers have become popular over the pa st few ye ars due to the pr oliferation o f p owerful di gital processors. We decided not to go down that route with X-EQ and we think you’ll agree with that decision. Maybe linear phase EQ is something we will explore in the future but… who kn ows? A n e qualiser not only c hanges th e r elative frequency balance of a signal but also its phase. If you EQ a sound until it sounds right or natural, then the chances are that you are EQing to make it sound in phase with the rest of the mix. We need say no more on this subject.

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Solid State Logic X-EQ manual Non- Linear Phase EQ