When mixing acoustic guitar, typically you can start with an EQ that cleans up low frequencies, before moving to compression and/or saturation. The compressor you choose will depend on the sound you’re trying to achieve, for example, an 1176 will work well in a rock mix.
How you mix your acoustic will vary depending on the sound you’re trying to achieve, so instead of giving you a signal chain, let’s cover the multiple options you have.
Let’s start with EQ, with which you’ll most likely want to attenuate the guitar up top right before it’s fundamental using a high pass. Then, if your acoustic sounds too boomy, let’s find the second harmonic, create a bell, and attenuate it, or amplify it if it sounds too thin.
For our demonstrations let’s listen to a double-tracked acoustic that’s a little too boomy.
If you recorded your acoustic with a Focusrite or Presonus interface, that’s totally fine but it may sound a little too clean for what you’re trying to achieve. If that is the case, try a pre emulation and increase the input gain to cause some mild harmonic distortion.
Depending on the one you choose, you may also have an EQ section, with which you can make the changes we performed in the previous chapter.
Let’s listen to the guitars run through this preamp, and with the EQ enabled.
The compressor you choose when mixing an acoustic has a huge impact on its timbre - if you want a percussive, more rock-inspired sound, try an 1176 emulation and utilize faster attack and release times. This creates distinctly percussive sound and even some transient expansion due to added distortion.
Let’s listen and notice how this makes the acoustics sound more in line with a rock mix.
If you want your acoustic to sound more like it belongs on a Beatles record or other pop record from the 60s, an STA emulation will work well. Its long release, along with distinct tube saturation creates a really full and warm sound, as well as a very dynamically controlled one.
I found this is a great way to create a full and warm sound, without losing high-frequency detail. Let’s take a listen to it.
An LA2A or other optical compressor is going to smooth out the sound with its program-dependent release, and a higher rate of compression on high frequencies. I’ll emulate it with the Pro-C2 by selecting Opto, changing the attack to 10ms, the release to auto, and using a soft knee.
For an even smoother sound, use lookahead to ensure the compressor captures the acoustic’s transient.
Let’s take a listen and notice how we lose some detail be create a pleasantly smooth sound.
An alternative to compression is saturation, with which we will both compress and distort the signal. Tube saturation is going to add a strong second-order harmonic, meaning our acoustic will sound warm and full, but the transients will retain if not gain some amplitude, creating a percussive sound.
This should sound somewhat similar to the Retro STA compression we used earlier, but with distinct characteristics. Let’s take a listen.
Tape saturation is going to create a second and third-order harmonic, as well as compress the overall signal more while reducing the high frequencies of the acoustic. As a result, the acoustic will sound more complex and lose some of its transient and high-frequency detail.
This should sound a little similar to optical compression, but again, it’ll have a distinct tone. Let’s listen and consider how tape saturation could be used inc combination with, or as an alternative for typical compression.
This is a general reverb sound that works really well for most acoustic guitars - typically it’s a room of studio emulation with about a 1 second decay time, with most reflections being on the shorter side. Typically the pre-delay is low, and little to no modulation is added.
Optionally, you can amplify some of the highs of the reverb to make the acoustic have a subtle shimmer to it.
Let’s listen to it at a higher level, but then blend it in and notice how it works both as an aggressive and a subtle effect.
For convenience I’ve been sending my 2 acoustic takes to a bus, on which I performed the processing. If you also use this setup, then the bus is a great place for a mid-side EQ with which you can affect the mono and side images separately.
For this session, I’ll attenuate the side’s lows, amplify the mid image’s mid frequencies, and boost the highs of the side image with a shelf.
Let’s listen and notice how the acoustic signal becomes more focused in certain areas but more airy and spacious in others.
For this session, I’ve panned my 2 acoustic takes left and right using typical panning - this will cause natural stereo expansion due to the phase cancellation between the 2. That said, you can also try binaural panning which uses psychoacoustic effects to place the signal in space.
Typical panning will be more mono-compatible, but binaural panning can be very convenient when trying to place an instrument in a complex mix.
Let’s listen to both and note their differences.
If you have 2 takes or a stereo recording of your acoustic you can use this trick. Keep the original 2 takes centered or un-panned, duplicate both of them, pan the duplicates hard left and right, and then change the output of the originals and duplicates to 2 busses.
On the duplicate’s bus, use the free Voxengo plugin MSED and mute the mid. Now you have an isolated side image channel, and an isolated mid image channel, on which you can add whatever processing you’d like.
I like to use a transient expander on the acoustic’s side image since it gives it a really enjoyable dynamic sound. Let’s take a listen.