Stereo Chorus - E-Mu MORPHEUS Operation Manual

EFFECTS SECTION

• Stereo Chorus

The function of a chorus device is to thicken the sound or to make one
voice sound like many. The way the effect is achieved is by mixing one
or more delayed versions of the signal in with the original. The delay
times used are too short to be perceived as a an echo, but long enough
so that comb filtering does not occur. In addition, the delay time is
varied to simulate the random differences which occur when multiple
instruments are playing together. A slight amount of feedback im-
proves the effect by creating multiple images of the sound as it recircu-
lates again and again. The delay times are slightly different for each
channel and the LFO phase is inverted on the right channel to help
contribute to the overall chorus effect. The LFO Rate and Depth set-
tings are critical to achieving a realistic effect with faster LFO Rates
generally requiring less LFO Amount and vice-versa.
The stereo chorus in the Morpheus is very similar to the stereo flanger
except that the delay time is longer. The delay times for the stereo
chorus range from 13 milliseconds to 52 milliseconds, compared with
the 26 microsecond to 6.5 millisecond range of the flanger.
Chorus simulates the effect of multiple instruments playing by creating multiple copies
of the sound using a varying delay time and feedback.
Chapter 5: Effects Section 49