THE HOME RECORDING CHRONICLES
Part I – The ‘Killer’ Guitar Tone
When you hear that ‘perfect guitar tone’ on professional recordings, are you convinced that if you had the EXACT setup that the guitarist on the recording does you would surely be able to dial in that sweet tone? Well, unfortunately, the right equipment may only be half of the battle. The other half almost definitely is due to the skill of the engineer on the other side of the mixing board, the microphone placement and equalization. Without that other element, you may end up being disappointed with a pretty "normal" guitar sound. In this series of articles, I will be taking a behind-the-scenes look into the some of the studio wizardry that allows your guitar idol to have that killer tone, as well as similar techniques for the other members of the band. My first installment will focus on microphone placement and equalization techniques.
In the beginning, it was very simple…one guitar plugged into one amplifier equaled a loud guitar capable of projecting its sound over the other members of a band. However, when it was discovered that overdriving an amplifier’s tubes by turning the volume full up created a smooth new distortion sound that added sustain and extra "edge", an insatiable demand for this type of new sound was created. With this demand, makers of amplifiers began to develop new products to satisfy the players. The Fenders, Marshalls, and Voxes of the world drastically changed the overall sound of the guitar, and paved the way for guitarists by bringing the instrument to the forefront of the band. Since then, there have been many advances and developments including Digital Signal Processors (DSPs), and new higher gain pickups that have brought the standard guitar tone to where it is today. Even with all of these developments, the studio guitarist must still rely on the expertise of the person behind the soundboard to round out the sound, and create what you hear on the albums of today.
Inevitably, there are two different ways to record the electric guitar. You can mike the amplifier, or you can record directly into the mixer. Being the purist, I will concentrate on the miking method.
CHOOSE THE RIGHT EQUIPMENT
When recording a guitar by miking the amplifier, there are many variables to take into consideration; will you be recording clean or distorted tones?; should you use tube or solid-state amps?; and what size of speaker should you use? As is the case in much of today’s music, guitarists will often elect to use distorted tones, and in doing so are faced with the question of which type of amp to use. There are many differences between tube and solid-state amps. One of the main differences is that tube amplifiers tend to have a warmer, more musically-pleasing sound because their signal range includes certain even-order harmonics that solid-state amplifiers are not able to produce. This may be due to the fact that the tubes that drive the tube amp constantly provide a low level of distortion that seems to work well with music, as opposed to solid-state amplifiers, which pass the signal in a more efficient manner, and do not generate this distortion. When it all comes down to it, the "tube sound" is preferred by many rock guitarists because it gives them extra fullness and tonal warmth at higher volumes. Finally, it is important to consider the size of the speakers. Generally speaking, the most versatile speakers are 10 or 12 inches, however, some guitarists will use 15 inch speakers to provide the bottom-end punch in the live setting. Unfortunately, 15 inch and larger speakers produce far too much bottom-end to be used effectively in a studio situation. The ten and twelve inch speakers provide a good amount of bottom-end that is easily manageable in the studio. Using guitar speakers that are any bigger than 12 inches in a studio situation can generate an abundance of tones in the 80Hz and below range, which can be responsible for an unwelcome low end distortion and a muddied tone. In other instances, the microphones being used may not be equiped to handle such frequencies therefore causing low-end distortion.
Once you have chosen your rig, and are getting ready top record, you want to decide what type of guitar sound you are going after, the very present sound, very ambient (Room echoed/reverbed) sound, or somewhere in between. Although these sounds can be simulated by effects-processors, it is best to use the natural sound of the room (or lack thereof) to your advantage. The size of room in which you are recording and how reflective the surfaces are can make a huge difference in the type of sound you get. Since the amount of ambience (room echoes) the microphone picks up during the recording determines how close or distant the instrument will sound on tape, the bigger and more reflective the room’s surfaces are, the greater the psycho acoustic effect. The environment in which the instrument is playing seems larger. Adversely, if you are going for the clear, present sound, you want to try to find a room with many absorbent surfaces such as carpet and furniture that will ‘deaden’ the sound and prevent the sound waves from reflecting and generating ambience. If this is not possible, you can create ‘baffles’, which are made of soft material and are placed in front of the amp and microphone. Baffles can be as simple as a bed pillow, and help to absorb the majority of the sound from the amp before it is able to reflect off of the surfaces in the room.
Before I get heavily into the mike technique, there is one important point I would like to address - Microphone distortion.
*Similar to the human ear, microphones and the ear have one major commonality: neither ones responds well to very loud volumes. This should be taken into account when recording the electric guitar. If you are looking for a good clear sound on the recording, never run the amp at full throttle. Doing this can create a nasty low to midrange distortion. Your best bet is to find a nice moderate volume level at which you don’t have to turn the microphone gain up too high to keep the signal clear. Besides, most amplifiers will inherently have a fuller, warmer clean sound at low to moderate volumes.
Now onto the actual miking techniques.
Admittedly, there are dozens upon dozens of microphone techniques with regard to miking the guitar amplifier. I will examine two types: Close miking, and combination close-miking and distant miking.
Being on a budget, as I am sure many of you are (myself included), I find that the best microphone for the money is the Shure® SM57™, and I will be using that particular microphone for all close-miking purposes.
When using the close-miking only method, you will achieve a very present, non-ambient sound. To reinforce this idea, it is important to make sure that the amp is surrounded by baffle material and be off of the ground in order to ensure the sound isolation. The next step is the actual placement of the mike. The best way to approach this in the close-miking situation is to start by setting the microphone six or seven inches away from the speaker with the mike angled in at a thirty-degree angle toward the outer edge of the speaker cone. Be careful not to point the mike directly at the center of the cone because you don’t want to risk potential distortion or the overload of any one frequency. The main goal is to have the microphone capture the natural sound of the amp, whilst creating as little noise as possible. Additionally, when miking a multiple speaker cabinet, you want to determine which speaker is the cleanest sounding and has the least amount of rattles or buzz. This will ensure the cleanest possible recording.
Close/Distant Miking Combination
For the distant miking microphone, I am using an Oktava® MK319™ condenser. This microphone is optimized for vocals, but I have found it equally impressive on guitar. If you don’t have the means to pick up one of these mikes, I would recommend pretty much any condenser microphone.
This particular miking set up is used to get the ‘power guitar’ sound. Using both the close and distant mikes, you can give the track the effect of being a live recording by combining both the presence of the close miking and the ambience of the distant miking.
The first mike should be set up in the standard close mike configuration as explained above, with the exception of the use of baffles, as we are going to use the room ambience for the distant miking.
The second mike is the distant or ‘room mike.’ This microphone will be used to pick up all of the acoustics of the room and provide the ambience. Generally speaking, the best way to position it is to listen how it is actually picking up the sound. A good starting point is to set the microphone about two feet higher than the close mike, and set it about 6 feet back from the speaker. If the room is smaller, you can set it 2 feet back. It is also important that you place sound deadening foam or carpet directly underneath the mike to avoid any floor reflections. These reflections can potentially cause acoustic phase cancellation or a buildup of bass tones, causing the signal to become muddied and indistinct.
With this method, you want to make sure that the microphones are placed on two separate channels and recorded on separate tracks, so you can effectively balance the amount of ambience you want on the overall signal.
The goal of EQ’ing the guitar is to bring out the best frequencies, and cutting the frequencies that will likely clash with the other instruments on the recording. Make sure you have a strong idea of what kind of sound you want to end up with, so you can better tailor that sound around the other instruments. Note that this is totally subjective based upon what type of music you are playing, and the overall sound you wish to achieve. My best advice is to experiment until you find a good solid tone that doesn’t cancel everyone else out.
Close Microphone EQ Ranges
The frequency ranges of EQ for guitar are consistent no matter if you desire a distorted sound or a clean sound. You will find the bottom end, or ‘growl,’ of the guitar in the space around 100Hz. This frequency when boosted conservatively (2 – 3 decibels (dB)), will give the guitar the warmth, however, it is VERY important to be careful when tinkering around this frequency because at 200Hz you will find a frequency that in too large of an amount will destroy all clarity in a recording and ‘muddy’ it up. The ‘body’ frequencies can be found between 500 and 600Hz, and can be boosted slightly. By slightly, I mean 2 to 5 dB. The frequencies that bring out the psycho acoustics and give the guitar sound its ‘edge’ lie between 3 and 4KHz. Boosted slightly, they can provide a solid, cutting sound, however, used too heavily, they can be piercing and cause headaches. The 5 – 8KHz frequencies bring out the sibilants. A small boost (1-2dB) in this range will give the sound a little bit of ‘sparkle,’ and will bring out the sound of the pick on the strings. Finally, to give the sound some high-frequency clarity, you can boost the 10KHz range (Try 5 - 7dB). This will set the guitar apart from other instruments that may be playing in its register, such as piano.
100Hz Slight boost (2 –3 dB)
200Hz Slight cut (1dB)
5 – 600Hz Slight boost (2 – 5dB)
3 – 4KHz Slight boost (1 – 3dB)
5 – 8KHz Small Boost (1 – 2dB)
10KHz Boost (5 – 7dB)
Distant Microphone EQ Ranges
This mike is much easier to work with, as it depends on the sounds of the room which frequencies will be boosted. The only definites I would recommend are boosting the ‘clarity’ frequencies at 10KHz and up. Try boosting in increments of 3dB up to a maximum of 10dB for best effect, and generally try to keep the 10KHz frequency at about 2/3s that of the 15KHz frequency. The other important frequencies to pay attention to are the 100Hz, which you can slightly boost by about 1.5 – 3 dB, and 200Hz, which I would cut by about 2dB. That will maintain signal clarity while eliminating the ‘muddy’ sound.
After that, I would recommend that you experiment with the frequencies we used on the close microphone. Depending on your particular room, you will have to adjust them accordingly, and results will vary.
This concludes the first installment of THE HOME RECORDING CHRONICLES. Tune in next time for tips on how to record drums effectively without having to worry about microphone phase cancellation. For now, I bid you adieu and happy recording