Our friends at Sonarworks are back with another brilliant guest post. This excellent article shares ideas for creating space in your mixes when using headphones. This article was written by Barry M Rivman. Barry explains the advantages of mixing on headphones and how to use them to create three-dimensional mixes using reverbs and delays.
Creating The Illusion Of Space For The End Listener
The dimensions of a mix is very important that tends to escape the amateur mixer. There is nothing wrong with a two-dimensional mix but a three-dimensional mix creates the illusion of music occurring in reality which is more satisfying to enjoy from the listening experience..
Our ability to perceive three-dimensional space with speakers is limited due to physical characteristics of the room they are in. Reflections, distance between the speakers, the natural reverb of the room plus the position of the listener all tend to smear our ability to hear a three-dimensional soundscape on monitors.
With headphones, the “space” exists solely between your ears. By eliminating room reflections and variations in your listening position relative to the monitors, headphones make it easier to hear and control the spatial aspects of a mix. In essence, the sweet spot moves with you locking the subtle spatial cues that enable us to localize sound in place.
“The effect that modern sound reproduction strives to achieve is the creation of an acceptable illusion in the mind of the listener.” - Richard Heyser
Since it is much easier to hear and control the three-dimensional qualities of a mix on headphones, it stands to reason that headphone mixing is the key to creating an engaging and satisfying illusion of sound moving in reality space.
Opening Dimensional Doorways
To mix three-dimensionally we have several tools that can help us get there. However, the most important in terms of the front-to-back placement of sound in a virtual soundstage are time-based effects. Time-based effects include reverb and delays. We do have other means to bring sounds forward or backward in a mix such as volume, EQ, distortion, transient modification, pitch shift, and enhancement, however nothing creates the illusion of three-dimensional space such as what reverb and delay can provide.
Beyond creating the illusion of space reverb also has quite a few uses that include:
- Blending instruments
- Thickening notes
- Making tonal changes
- Adding sustain to notes.
Reverb can also be used to create rhythmic effects as well. The most common use of reverb is to place an instrument in a soundstage since the first noticeable effect that reverb has on a sound is to push it backward in a mix. The problem is that using reverb to move sounds forward and back in a mix is not as effective as delays. Reverbs tend to mask notes, particularly when over used. In this context an easy work around is to use pre-delay as it doesn't wash out the sustain and ends of notes.
Using Reverb Pre-Delays
Reverb in its essence is a very complex series of closely spaced delays based on sound reflecting off numerous surfaces in a room. The important thing to note is that you shouldn't be able to hear the individual delays. Reverb has several components including the aforementioned pre-delay which is a measure of time before the first onset of reflected sound occurs. It follows that pre-delay is a function of distance which makes it the most important parameter in reverb units.
If you think in terms of distance travelled from an original sound source to the first reflection of that sound off a surface then the pre-delay control determines how far the source is from that surface (generally a back wall). It follows that a short pre-delay would move a sound back in the mix closer to the rear wall. A long pre-delay moves the sound forward and no pre-delay pins it against the back wall.
Long pre-delays have the added advantage of defeating the masking effects of reverb providing a more defined sound and a cleaner mix. Since pre-delay is measured in milliseconds then a 20ms pre-delay puts the back wall approximately 20 feet away. Keep in mind that in a physical room there is no guarantee that sound is going to hit the back wall first.
Sound between stereo monitors is an illusion and in our virtual space. The reflections of reverb are incredibly complex. We don’t hear sound coming from one side or the other but rather from front to back which is more clearly defined by pre-delay. So by using pre-delay we now have a means to place instruments in different positions in the sound field with the added advantage of clarifying them by allowing us to hear the dry sound before the reverb sets in.
When setting pre-delays for reverb, it’s best to use shorter settings, say between 20-25ms.
Creating A "Back Wall" With Delay
A single mono delay will create a “back wall” for a given sound source to help define the front-to back dimension of your virtual soundstage. Since lead vocals are the front-most focus of a song, it follows that they would determine the depth of your soundstage. The best place to start is to create a back wall for your vocals. A common delay setting for vocals is to use an 8th-note mono delay synced to the song’s tempo.
Let Us Know What You Think?
- How do you use reverbs and delays to "create space" in your mixes when using headphones?