The time-honoured use of headphones for tracking and overdubbing has been standard practice for decades, but it doesn't suit every situation. In this article Luke Goddard show how you can use loudspeaker monitoring as an alternative to headphones.
Why Headphones?
Using headphones to monitor during recording has become standard practice ever since engineers realised the benefit of taking monitoring out of (often large) rooms and redirecting it directly into the artists’ ears!
Before this time, vocal artists recording live with a band would simply go without monitoring or use loudspeakers in the studio for any overdubs. Over time this became less practical as track-counts and the subsequent need to minimise spill increased.
Why Loudspeakers?
When recording, we usually reach for the headphones without even questioning it. However there is another way, and if headphones are inducing red light fever, causing pitching problems, or aren’t practical to use for some other reason, having loudspeaker techniques in our toolkit can help.
For group vocals, maintaining the energy and interaction between performers without headphones can be hard to beat. Also, providing large numbers of headphones might not be possible.
How Well Does It Work?
With careful use, the level of monitor spill in the recorded tracks can be low enough to be easily masked by the mix. The mix below features four vocals (double-tracked lead, and double tracked harmony) that were recorded without using headphones.
Optimising The Room Acoustic And Loudspeaker Position
Generally, a more dead acoustic is better. If you need to set up speakers in a live tracking space, keep the overall level as low as possible and consider using improvised absorbers to reduce reflections into the room. Move or angle speakers away from flat reflective surfaces that cannot be treated.
Optimising The Monitoring Level
Ideally, we’re looking to run playback just below the level of the voice so that the artist(s) can hear themselves unassisted. If all is well, the playback level should feel slightly quieter compared to a sensible mixing level.
Below is some audio to illustrate the level I used to record the vocals above. Although monitor controls can be calibrated so that a given reference level produces a given SPL, sometimes a simple spoken word test can convey monitor loudness better.
Selecting And Using Mic Patterns
The aim is to use directional mics, keeping speakers in their nulls. Cardioid patterns naturally lend themselves to loudspeaker monitoring, and hypercardioid mics’ dead axes can work especially well when working with two speakers in very small rooms.
Figure of eight mics are often overlooked for vocals, but can be a secret weapon when recording group vocals with loudspeaker monitoring. In the right acoustic, placing small monitor speakers either side of a figure-of-eight array is ideal for overdubbing choirs.
Using Monitoring Polarity
Changing the polarity of one monitor can be used to reduce monitor spill into a mic on the principle that an inverted signal will cancel its mono “twin” to some extent at the mic. I find this technique highly effective:
Ensure the mic is equidistant from the two monitors
Mono the cue mix
Invert the polarity of one monitor.
Be aware that the monitor signal should be mono’d then inverted. If you invert in the DAW, before pressing a hardware mono button, your centre instruments will disappear! If this happens, simply do it all in your DAW using two plugin instances (one for mono, followed by one for invert) to correct this.
Harnessing Spill
Some spill is inevitable with loudspeaker monitoring, however there is an additional way to use polarity to reduce it further when using any static set up (ie, with the mic on a stand).
Record again with the cue mix playing, but without the artist singing. Invert the polarity of this “spill only” take.
Mix at the same fader level as the original take and duplicate processing before inversion. Group both tracks to mirror any automation/editing.
This technique is worth employing if you are doing multiple parts. Its benefit is perhaps a little subtle for a single part, and I find this technique cancels the bottom end more than anything. Cancellation is compromised slightly as the presence of the artist in front of the mic will change the soundfield a little. You can stand in front of the mic yourself to counter this if you like!
Which Wins?
Monitoring without headphones whilst tracking can produce great results with a little forethought. Headphones have rightfully found their place in the studio, but we can also harness loudspeaker monitoring effectively in a controllable way whenever the recording needs it.