In a multi-way speaker system, the crossover filters as well as the transducers inevitably introduce phase distortion and consequently also variations of group delay.
The group delays are higher in low frequencies than in high frequencies. Theses create a separation in time between the low and high frequencies which typically gives multi-way speakers a “hollow” sound.
In a limited frequency range, an all-pass filter will allow to alter the phase without influencing the amplitude.
The CPR system is made up of several all-pass filters each acting in a specific range of frequency and together obtaining a Compensated Phase Response. This then provides a constant group delay that is kept to the bare minimum through our entirely analogue technology.
Thanks to the CPR system, the placement of sound in the actual sound space is perfectly accurate. Amongst others, this technology allows designing a surround sound systems with different types of PSI Audio speakers whilst maintaining a perfectly accurate phase response.