Much of the time, the DI/pickup in acoustic guitars gets a bad rap. Notoriously midrangey and ‘honky’ in overall character, they can dramatically lower the quality of a mix - especially when overused. There are however ways to make them sound good and use what they give you for your benefit. Here are a few ways that I incorporate them in the studio where they can be altered, twisted, added to and manipulated to help make that acoustic guitar part really shine.
To begin with, I always use a microphone on an acoustic guitar along with the DI. The microphone is what captures the space, depth and air of the guitar. Along with that, I run a DI into any number of pieces of hardware and/or software that allow me to increase the clarity and punch of the microphone. By having access to both, it becomes easier to craft a bigger acoustic sound at the mix stage.
I have a number of acoustics for my work, from 4 string cigar boxes to nylons, resonators, dreadnoughts and 12 strings. On each one of them, if it wasn’t already built in from the factory, I have had DI pickups installed. This is an individual preference, but I have found the simple K&K Pure Pickups, installed on the bridge plate and output via ¼ inch jack with either 3 or 4 head transducers, delivers a natural sound. And equally as important, it lets me plug the guitar into a tuner, because constant tuning is critical when it comes to recording.
Virtually every guitar part I do in my studio runs through the Tech 21 SansAmp Bass Driver DI. A bass driver? Yes. I have found that it fulfils a number of needs for me. The DI's from all my guitars go into the Input and I use the Parallel Output to feed any number of devices, from amp heads to pedalboards. This Parallel Output is not affected by any of the active EQ setting, offering a clean secondary signal path. There are a useful variety of EQ options on the DI, including Treble, Mid, Bass, Presence, Drive and frequency shift buttons. While this device is optimized for bass, I have found it to be an invaluable guitar DI tool. Sometimes, depending on the guitar, I bypass all the effects (EQ) and other times I use it.
The first line of defence against a mediocre DI sound is to EQ it. In my experience, cutting down some of the honky mid range around 500 Hz - 2 kHz, as well as some of the low mids around 200 Hz is a great starting point. To add a bit of sheen, I’ll boost around 10 kHz, but that depends on how it blends with the actual microphone sound. A very useful EQ for this purpose is the FabFilter Pro-Q 2 EQ. Specifically, I use this because when you grab and hold a band of EQ, it isolates it so that you can hear exactly what you are cutting or boosting. Then when you let go, it goes back to the full mix. This way, in just a few minutes, you can quickly get that DI sounding much better.
Another quirky EQ that I use on acoustic DI’s is the FabFilter Saturn, which is a multiband distortion, saturation and amp modeling plug-in. But the interesting way that it lets you ‘chop up’ and manipulate the EQ bands is why I use it. You can for example add a touch of amp saturation to just a narrow band, while cutting those around it. (No I’m not endorsed by them!).
There are two other plug-ins that I have found quite useful for acoustic guitar DI’s, both from Universal Audio. The first is Ocean Way Studios, which combines elements of room, source and mic modeling. I add this to the dry DI signal to give it a bit of depth and a subtle bit of EQ, by altering the brightness or darkness of the room. The other plug-in is unique Sound Machine Wood Works, which allows you to “re-mic” and simulate the mic recording of your guitar. You can use the modeling with your piezo pickup to go between Studio, Dreadnought and Jumbo acoustic tones, as well as dial in the amount and individual Pan of Neck and Body EQ. If you use the mono to stereo version, it lets you pan the neck and body images to create more sonic width.
Before Sound Machine
... and after
Another method I sometimes use is to take the aforementioned Parallel Output of the Bass Driver DI and send it into a small stereo pedalboard for processing. While this is not always called for, some of what I do in TV-land is ambient and moody guitar music, and by capturing the mic, DI and a stereo effects path, I have a lot of sonic options.
My stereo effects pedalboard can ‘plug and play’, with a variety of pedals based upon my needs. A typical configuration will be a TC Electronic Hall of Fame 2, TC Electronic Flashback 2 Delay and Looper and Eventide H9 (or two!). However, I also sometimes run the DI through my Line 6 Helix, usually bypassing the amps and using the effects only. These options allow me to record a left and right output and manipulate the acoustic DI tone in a variety of ways. Again, this will usually be added to my DI direct sound and of course, the microphone.
There are options available other than the ones mentioned above that can help you get a better DI sound. Pedals such as the LR Baggs Venue DI Acoustic Preamp/EQ/DI Tuner, or the Grace Designs ALiX Instrument Preamp/DI/EQ allow for creative tone shaping of your DI, as well as the ability to send it out to either a PA or amplifier, as well as a tuner. When used in the studio, they offer the ability to add quality EQ and filtering to shape the sound before it even hits your DAW.
If you’ve got everything set up, use it! I tend to double the acoustic guitar part to make it sound bigger which also helps create its own natural bit of chorus effect. Below is just a single use of the mic and DI together, and then the same technique doubled and panned left and right in a full mix.