With the HEDD Lineariser® plugin, we have created a unique solution for one of the most challenging problems in the history of loudspeaker designing: Linear Phase Response. What does it mean and why will your HEDD studio monitors sound better than ever?
Well, all loudspeakers regardless of size or construction cause phase errors. This means that not all frequencies leave the speaker at the exact same point in time. This has to do with physics: The fundamental relation between time and frequency is expressed by the so-called Fourier Transform, which explains that corrections in the frequency domain will inevitably alter the phase response – and vice versa. You can’t have both, linear frequency and phase response at the same time, at least not in an analog loudspeaker design.
The above said is true for complete speakers as well as for some of its ingredients. Think of a monitor as a complex network of different filters. The voice coils for an example are low pass filters in itself, and so is the volume of a cabinet. A tweeter sends out high frequency material significantly earlier than midrange and low frequency drivers – another source for phase problems. All these timely aberrations vary with frequency and together they build the phase response of the complete loudspeaker. Phase problems can make a speaker’s stereo image sound somewhat mushy and undefined.
Ideally the phase response should be displayed as a straight line, indicating a perfect timely relation between the different sound layers emanating from the speaker.