1. Demonstrate two of the three types of
modulated short delay effects (flanger, chorus).
Luciano de Oliveira
Introduction to Music Production
Lesson week 5

2. Luciano de Oliveira
- Brazilian, living in Porto AlegreRS
(South)
- Favorite out of work activities:
- read books and watch movies.
- Travel
- Play bass-guitar
- Receive friends at home
- Play Squash

3. Introduction – Delay Effect
• Delay is one of the most common effects used in audio production
today and put simply is a form of echo.
• A delay processor sends the input signal to the output at a later
time that is set by the delay time. This can be milliseconds or many
seconds. The signal is combined with the original in an amount set
by the mix control. The number of delay repeats is determined by a
feedback control - the more feedback the more repeats.

4. Introduction – Delay Effect
• Any delay under 10-20ms is inaudibly separate from the original signal.
Beyond 20ms ones ear begins to think of the 2 signals as different
sounds.
• There are many varieties of delay including mono, stereo, multitap and
slap back.
• Most delay processors allow the signal to be delayed as a rhythmic time
value, such as quarter notes. This type of delay is most common in
modern day music and can form an integral part of the music’s rhythm.

5. Common Controls
• Delay – The delay control determines the delay time used to create the chorus/flanger
effect. Usually, flanger-type effects use short delay times while chorus-type effects use
medium to long delays.
• Feedback – The feedback control determines the amount of effect signal fed back to the
input, which in turn affects the intensity and character of the effect. Turning it extreme
left or right produces different flanger effects with a distinct resonance, while keeping it
centred produces a more gentle chorus effect.
• LFO Rate - The LFO Rate determines the frequency of the LFO modulating the delay time.
The higher the value, the faster the sound will oscillate.
• LFO Sync - The LFO sync control allows for the LFO to be synchronised to the songs
tempo, in one of 16 possible time divisions.
• LFO Freq. Mod - The LFO Freq. Mod control determines the depth of the LFO
modulation, i.e. by how much the frequency parameter should be modulated. At zero the
effect is static

6. Chorus
• The chorus effect processor works by delaying the input signal by
about 15 milliseconds and mixing it back into the original signal.
• The delayed signal is then slightly detuned in pitch from the other
which is controlled via the modulation rate and depth controls.
• A low modulation rate and depth adds a subtle change
comparable to an ensemble.
• Add more depth (pitch shifting) and the chorus becomes more
aggressive creating a warbling sound.
• Chorus is most effective in thickening pad parts or string
ensemble sounds but is also effective on vocals and guitars.

7. Flange
• Flanging is similar to chorus in that it occurs when two identical
signals are mixed together.
• One signal is time-delayed by a small and gradually changing amount.
• The modulation produces a swept 'comb filter' effect; peaks and
notches are produced in the resultant frequency spectrum, related to
each other in a linear harmonic series.
• Varying the time delay causes these to sweep up and down the
frequency spectrum.
• Part of the output signal is usually fed back to the input (a 're-
circulating delay line'), producing a resonance effect which further
enhances the intensity of the peaks and troughs.
• Flanging works best on harmonically rich sounds such as bright string
pads, although it can also be used on drums and cymbals.