Do you know what the difference is between an acoustic guitar and a trampoline? One of my favorite music jokes. The truth is that acoustics can be a pain. Getting a good acoustic sound in the studio usually involves several condenser microphones, some compression, a room mic, and a lot of attention to detail. In a live setting, most acoustics get plugged into a direct box and are given very little thought. The result is usually a dull, unatural ’nylon’ sound. To combat this we have to follow one of my #1 rules in doing sound.

One of my first rules of doing live audio is that you can’t polish a, um, mud pie. As the audio engineer, you should strive to re-create the audio in the house as closely as possible to the audio coming from the stage. Unfortunately, if a guitar sounds dull or boomy on stage, then you’re not going to be able to magically make it sound clear and balanced in the house.

This Sunday, walk on stage to hear the acoustic guitar acoustically. That is the sound you want to hear from the house speakers. Does it sound dull? Muddy? Ask the musician when the strings were last changed. It wouldn’t surprise me if the answer you got was, “Sometime in 2007.” Please notice what I’m stressing here. We haven’t talked mics, direct boxes, EQ, compression, FX, etc. If we can start with a quality audio source, we may not have to mess with all the other processing. Let’s keep it simple!

That being said, I always prefer a mic for anacoustic, if possible. Don’t force your guitar player to sit on a stool or stand completely still or move him as far away from the drums as possible just so you can use a mic. I doubt many of you will actually have the luxury of using a mic, but if so, even a 57 will sound good. Small diaphram condensers will probably be better though. Try aiming the mic 1/2 way between the hole and where the neck leaves the body of the guitar.

Mostly likely, though, you will have to use a direct box, and that’s OK. If the guitar has that nylon-string sound without a lot of clarity, be patient, because it’s not an easy quick fix. Our goal here is not to create a pristine acoustic guitar, but rather one that sounds more percussive. Add some high end, and play around with adding and cutting the mids. If your board has a high mid and low mid, try adding some of the high mids and removing some of the low mids. We want to hear the pick coming off the strings, so that when the whole band is playing, the acoustic cuts through percussively, and just fills in the sound acoustically, almost like a filler sound, even if it’s driving the song.

If you have reverb available, try adding a little, but avoid a huge room sound that takes 4 seconds to decay. Just use a smaller room sound, or even a plate, with 1-2 seconds of decay. All you’re trying to do is smooth the percussive edge and make the guitar become part of the whole band and not draw too much attention to it.

Adding a compressor is not a bad idea, especially if your play switches from strumming to picking a lot. Compressors are a tricky piece of gear though. When they are doing their job, you don’t notice they are there- just like your job running sound! You don’t want to suck the life out of the strumming, so using a longer attack setting: 50-100ms. Keep your ratio low, under 4:1, and actually start around 2:1. If at any point you feel the compressor is hurting the sound rather than helping it, take it out. You should not see any gain reduction when the guitar is being picked, and during the strumming, only shoot for 3-6dB of reduction.

Acoustic guitars can feedback if they are too loud, especially in a monitor that is pointed right at it and really loud. Ask your guitar player to use a feedback buster (under $10), but again, only if needed. This will help the monitor audio from rolling around inside the body of the guitar. Otherwise, you may have to take a lot of the bottom end out of the guitar, which will again create an unatural sound.

This is a tricky instrument. If you need to work on it, ask your musician to stick around after practice or to come in early. Don’t be afraid to experiment on the sound, just try to learn something everytime.

I used a photo of The Elms on this post since I recently got to run sound for them here in Columbus when they opened for Peter Frampton. It was a gorgeous night, and with 1,000+ people outiside all having a good time, I had a good time. I plan on writing a tech review of the gear and about the logistics of the show, so come back soon!