Audio Effects – Phase Shifting & Chorus

November 15, 2006

Audio effects! Is there anything they can’t do? We’re continuing on with this series, this article being part 4 in the series. I was thinking about the best way to abstractly describe the function and importance of audio effects and knowing your effects well. This is what I came up with. Your studio is basically your tool box, with all your effects and gear being tools in your tool box. Most people know their tools pretty well, but most are not masters. To hammer a nail, ideally you’d want to use a hammer. It would be the most efficient and easy way to do it. You could use a screwdriver or even a wrench to do the same job, but it may take more time and your end result might not be up to your standards. So, basically I’m trying to say, you need to master all of your tools before you can produce and edit music correctly. Well, that was a long winded explanation for a simple idea. Moving on. 

Today we’re going to be discussing phase shifting and chorus effects. Phase shifting is kind of cool, and I’m really excited to delve into how it works. Chorus is a basic effect, and may not elicit excitement in most of you. But like any effect, it’s one of those that is used all over the place so often that you probably can’t tell when it’s used. Anyways, let’s discuss how these effects work and why they work the way they do.  

Phase ShiftingThe first phase shifting effect units were pretty simple. Phasing was originally produced by copying the sound onto two analogue tape decks and mixing them together. One deck was run slightly faster than the other and the phasing effect was created by the rising and falling “wave interference” of the two signals. The term phasing more specifically refers to a swept comb-filtering effect where there is no linear harmonic relationship between the teeth of the comb. A flanger is a sub-type of phaser, with its effect usually being more precise, produced by the harmonic relationship of the comb filter being linear. Phasing effects in modern music are typically used in conjunction with electric guitar, and it is also used to “sweeten” the sound of electric keyboards. Also, a fun fact is that a phaser was used to create C-3PO’s voice in the movie Star Wars because the phaser sound lends a synthetically generated feel to the human voice. 

ChorusWhen chorus is used, individual sounds with roughly the same timbre and nearly the same pitch converge and are perceived as one. When it is successful, all the sounds hold the same tune and it sounds as if they all came from the same source. The chorus effect is enhanced when the sounds originate from different moments in time and from different physical locations. To produce this effect artificially, a computer processor takes an audio signal and mixes it with one or more delayed, pitch-shifted copies of itself. This results in the production of a single sound that simulates the sound of several instruments or sounds. 

Alright, this wraps up the 4th installment in my audio effects article series. I never knew how the chorus effect worked, and now that we discussed it, it seems like the name of the effect is exactly what it does. And phase shifting was sort of a carry-over from the article discussing flange. But since flange is basically a type of phase shifter, I think that it was very important that we discussed it in this article. Anyways, hope you all learned something in this article. Please stay tuned for my next installment in this continuing series.  

Jason Cole and DiskFaktory Mastering offer great professional mastering services and information regarding audio engineering and CD mastering in California. Get the professional cd mastering information you are seeking now by visiting http://diskfaktory-mastering.com/evaluation.htm

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: