Hopefully, the past four Frets Learn columns have helped you get your best acoustic guitar tones in the box. Now it’s time to maximize their effectiveness in the mix. One major factor involves the number and nature of all instruments in your arrangement. We consulted with Grammy-nominated producer/engineer Travis Kasperbauer, who teaches digital audio at the Academy of Art University, to compile some tips. All of these can be applied to the tools commonly found across popular digital audio workstations, and all are universal to mixing acoustics.
EQ ADVICE: START HERE
The multiband EQs found on DAWs have similar features. The buttons on the far left and right that look like arches engage the hi- and low-pass filters, which trim the frequencies above or below a given point. Set a high-pass filter on the left, with a cutoff at 80Hz, as there’s no useful acoustic guitar information below this frequency. (See Fig. 1 for this and the following information.) As the number of instruments competing for space in the bass frequencies increases, raise the cutoff point for the high-pass filter up to around 200Hz.
Moving inward, the two buttons that look like tuning forks engage shelving, which functions like old-fashioned bass and treble controls. Start by boosting 1kHz, and search for the appropriate amount of “air” from there. In the middle of the plug-in are a few parametric, or peaking, EQs. All hollowbody instruments have some inherent unpleasant frequencies in the low-mid range. Make a dip right around 450Hz, and solo the track. Find the worst sound by searching around and raising the level in that range, and then boost it until it sounds obviously awful. Next, cut that frequency by the amount of boost it took to clearly identify it. Now unsolo the track and bypass the EQ for comparison. If the other instruments are easier to hear with the EQ engaged on the guitar, then you’re at a good starting point. Customize from there.
After an acoustic track is equalized, we can maximize the tone via a compressor plug-in, which turns down the loudest notes and brings up some of the quieter elements. Compression can help articulate a gentle part, such as a fingerstyle track. Picked or hard-strummed parts generally require less compression. Set the threshold at the volume where the VU meter starts to indicate significant reduction. Start with a ratio of 4:1. Bring the threshold down a bit, and compensate for the volume reduction with the make-up gain.
ADDING MODULATION AND AMBIENCE
Using a chorus plug-in can provide a fuller sound, simulate a 12-string and even cover up for dicey intonation or tuning. For adding ambience, a plate reverb setting is usually awesome. Plate reverbs has adorned countless classic acoustic tracks, so it’s a great throwback to the salad days of the singer-songwriter era. Room reverbs are a tried-and-true way to define size and space, from a small room to a concert hall. A delay with a time longer than 50ms will extend the space. You can also use delay as a rhythmic tool by trying different note values and adjusting the decay time. The key to any effect’s usefulness is the balance of wet-to-dry mix. You generally want to “feel” the effect on the guitar without hearing it overtly.
Pan is short for panorama, which defines where your track sits in the sonic landscape. For solo acoustic or guitar-and-vocal tunes, set the pan to the middle and let the ambience fill out the sides. On a song with multiple instruments, center primary elements of the sound and pan others to the sides. Acoustic guitar works well when panned opposite of other percussive instruments, and it can work well panned opposite of an electric guitar, too. If you recorded an acoustic using multiple mics, keep them together in the stereo field. If you recorded an additional direct signal, panning it to another location can be effective for definition or allowing space for effects, but that can be limited if it’s the same performance. If you double-tracked a part, then by all means try panning it opposite for sonic spread.
Finally, consider automating the volume of your acoustic track so that it shines at the most opportune moments, and then tucks away to let others stand out. Think of the mix holistically; soloing each track to perfect it individually leads to a cluttered mix. Be experimental, but remember that balance is key. Take the listeners on an enjoyable journey with unexpected twists and turns, but don’t jerk them around.