The techniques of flanging (signal + delayed signal) and processing with a phaser (signal + all-pass filtered signal) are discussed. The considerable differences between the results of the two techniques are noted. It is shown that in the limit of an infinite number of one-pole all-pass stages processing with a phaser can become equivalent to flanging. It is shown that for a finite number of stages a phaser is optimized if all stages have the same time constant. In that case the peaks and zeros of the transfer function are most uniformly distributed in frequency.
This paper costs $33 for non-members and is free for AES members and E-Library subscribers.