AUDIO TIPS: Acoustic Guitar



Tip #2: ACOUSTIC GUITAR
by Chuck Standish

Getting a faithful reproduction of an acoustic guitar or bass takes a good deal of patience to master. Generally speaking, don't put the mic directly in front of the sound hole, as this is an invitation to mud. Try placing the mic either ahead of or behind the sound hole, and aimed towards it. An SM-57 will give you a good tone with enough experimenting, although typically a more expensive and transparent condenser mic is preferred. Acoustic guitars also seem to respond very nicely with a room mic to pick up the ambience, or just use a single mic far enough away to pick up both the guitar and the room's reflections.

If you'll be distant micing, it's better to use a large diaphragm condenser in omni mode. This will give you the most natural sound of the guitar's interaction with the room. For obvious reasons, you'll need a very quiet area to record this way.

The placement of the mic on the guitar amp offers you a great deal of sonic flexibility. Try monitoring through headphones while someone else plays while moving the mic to slightly different positions on the cone, at different distances and different angles. You should be able to get a good sound without using EQ if you're patient enough. This is the best way to get a natural sound as EQ colors your recording too much if used heavily.

When recording an acoustic guitar, it is always a good thing to try the traditional techniques such as the X-Y technique. This is where two mics have their capsules very close (without touching) pointing to the instrument at a 90-degree angle from each other. There is also the stereo 3-1 rule, which has it that if the Left Mic is 1 foot from the source, then the right mic must also be 1 foot from the source but three feet from the 1st Mic.

When recording an acoustic guitar using the pickup/mic combination, you can pan the two signals left and right to get a broad stereo sound, but make sure that when you check the sound in mono, that there's still some signal left. Be on the constant lookout for phase cancellation issues. These issues can arise from something as subtle as the player shifting his/her body position in relation to the mic.





Recording a nylon, or 'gut-string' guitar presents its own set of challenges for the engineer. Use a condenser mic, this time placing it about ten inches away from the guitar. Aim the mic about three or inches up the fret board, pointing towards the picking fingers. This will result in a reduction in the 'boominess' (because of the natural roll-off due to the cardioid pattern being off-axis) while getting all of the attack of the picking fingers.Always try to get three things when recording acoustic guitar. The sound of the pick hitting the strings, the "wooden" sound of the body and a sense of pressure and movement coming from the strumming hand. To get these, experiment with mixing and matching different mics, such as PZM with dynamics, condensers with electrets when trying to capture a stereo image of the acoustic.

When recording an acoustic instrument, remember this tip. A limiter/compressor will almost always help you get a better sound. It's usually 'best practice' to track the instrument with no compression at all and add it in later. This gives you the widest possible range of options during mix down.

Here's the trick to getting a nice fat country/pop sound on the acoustic guitar. Place the microphone about 6 to 8 inches from the guitar's sound hole, but angle the mic toward the area where the fretboard and the sound hole meet. Avoid pointing the mic directly into the sound hole. If you do, it will be much too full and boom-y. Use the compressor/limiter to knock down any peaks (3:1 ratio), and set the threshold a little lower to give it a slightly "squashed" or tighter sound. Set the threshold higher to just limit the peaks and give a more open sound.

When recording an acoustic guitar, it is always a good thing to try the traditional techniques such as the X-Y technique. This is where two mics have their capsules very close (without touching) pointing to the instrument at a 90-degree angle from each other. There is also the stereo 3-1 rule, which has it that if the Left Mic is 1 foot from the source, then the right mic must also be 1 foot from the source but three feet from the 1st Mic.

In order to get that punchy, 'woodsy' sound on the acoustic



guitar (read: Mellenkamp) try using medium gauge strings and a little more compression than you would normally use. Gently boost the mids on the EQ adding a little around 700Hz-1.2K. Remember, record it straight and add EQ and compression after.

To get that 'silky sounding' crispness on the acoustic guitar, try something in the 8-10K range, but be careful, too much will add noise to the track. Positioning the mic so it angles toward the pick will give you more attack, but considerably less 'sweetness." Another benefit of placing the mic at an increased distance from the guitar when recording a nylon stringed instrument is the fact that the added distance will pick up some of the guitar body's resonance. A compressor/limiter is necessary in this case because of unexpected peaks. A 4:1 ratio is a good place to start, but set the threshold fairly high so that the most of the guitar's natural dynamics are left intact.

Another simple but effective trick is to have the acoustic and electric guitars play parts that counter each other rhythmically (giving them each their own space), and hve them each play in a different octave. That will give you a full sounding track that remains open and airy at the same time.

You can also make an acoustic guitar sound bigger or more rock-like by panning the original to one side and a delayed signal (short delays are best) of the same guitar to the other side. That effect can be taken one step further by using the pitch change option on your delay to 'de-tune' one of the guitars just a pinch (one cent is a good place to start). The delay will provide the brain with the 'psycho-acoustic' information it needs to perceive the guitar as bigger, while the pitch change will make it appear 'fatter.'