- by Kevin Deal
Mixing songs is definitely fun and exciting especially when you’re almost done with a finished product. After recording a good set of vocals and instruments, nothing can make a song more refined than using the right effects. There is no denying that effects are able to give songs that extra pinch of pizzazz and depth as well. To be more specific, modulation effects make the difference between an ordinary song and a big hit.
The problem with mixing and adding modulation effects is that there are so many ways to add effects that it can get quite confusing as to which one to use. It definitely takes a good ear, creativity, and a significant amount of experience to be able to know which effects to put at which part of the song. Although the process is complicated, you shouldn’t be disheartened to try and experiment with modulation. To encourage and guide you through this, we have noted some facts on modulation effects that you must know before you can start mixing.
How do modulation effects work?
Modulation effects work by delaying an incoming signal by a few milliseconds and using a low frequency oscillator (LFO) to modulate the delayed signal. An LFO has frequencies so low (around 0-20Hz) that they cannot be heard, but its varying effects (depending on how it is used) can be heard when it modulates a signal. It is safe to say that LFO is responsible for controlling and producing the different modulation effects. The parameters used by LFO are speed/frequency and depth/intensity. What differentiates each effect from the other is the use of delay time, which will be further discussed for each type of effect.
The types of modulation effects
There are many different types of modulation effects that are well known in the industry. These include: phasing, flanging, chorus, vibrato, and tremolo.
Phasers have the shortest delay time among all the types of modulation effects with only a few milliseconds of delay. The phaser effect basically splits an incoming signal into two. One is retained as the original (dry) signal, while the other is slightly out of phase. By combining the two signals, the amplitudes of both signals reach their dynamic range at different times.
Many popular rock artists like Led Zeppelin, Van Halen, and Queen all used phasing in their music.
Flanging is usually used to give an underwater, metallic, or space/sci-fi effect to sounds. It is similar to chorusing, but has a shorter delay time of 5-15 milliseconds. With flanging, you could also feed the effect signal back into the original source sound. This process results to phase cancellations and “comb filtering” effect.
Flanging was a popular vocal effect in the 70s. In fact, it is used by some to give a Beatles vocal effect on their track. The effect is said to have been invented in the Abbey Road Studios. The effect is also great on guitar tracks.
Chorusing is similar to flanging, but with a longer delay time of around 15-30 milliseconds. In fact, it has the longest delay time of all the modulation effects. The delay time is modulated with an LFO. The modulated signal is then mixed with the dry signal, but there is no feedback, unlike with flanging. This effect is used to enrich and add depth to a track. It gives an effect of playing many instruments or vocals in unison. It is a very versatile effect because it can be used on many instruments and vocals.
This is a very popular effect used by many legendary guitarists such as Kurt Cobain.
This effect involves a subtle shift in pitch which is perfect for tracks that already sound great. Although it is a subtle effect, it makes a big difference in turning a boring song into an interesting one. It is often used for instruments like guitar, electric piano, or Hammond organ.
This effect involves modulating the amplitude of the input signal to create periodic volume and frequency changes. Tremolo is used to add movement and dimension to a track. It is often used on traditional guitar combos.