Conventional loudspeaker crossover networks of slope greater than 6 dB/octave, when properly implemented, result in a loudspeaker system whose acoustic transfer function, although of flat magnitude, has all-pass phase characteristics. The system is thus non-minimum phase, and complicated phase equalization using delay equalizers is required in order to render it linear-phase and so transient-perfect. A number of attempts are currently being made to acoustically align such systems by deliberately either introducing or eliminating time delays between the drivers and using conventional minimum-phase equalization to flatten their overall frequency resonse. It is shown in this paper that no choice of inter-unit time delay can render the system minimum-phase, and hense that minimum-phase equalization cannot make such a system both flat and phase linear.
Click to purchase paper as a non-member or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!
This paper costs $33 for non-members and is free for AES members and E-Library subscribers.