Contrary to what many might think, just having great equipment doesn’t automatically guarantee that you’ll capture great sounds. Sure, having expensive vintage equipment helps, but when it’s all said and done, technique will trump equipment almost any day. I’m constantly amazed at the sounds that some people can get out of just an M-Box and an SM-58.
Here’s a list of variables that you must be aware of when recording just about anything. While you can’t really quantify exactly how much each variable contributes to the way something ultimately sounds because each situation, even within the same project, is unique, you can generally break it down to something like this:
The Player and the instrument contributes about 50% to the overall sound. Sometimes a little more, sometimes a little less – but always the greatest portion. You can prove this to yourself. Get a player who’s not yet that accomplished and record him with his equipment. Chances are it will sound pretty mediocre. Then get a great player to come in and play on the same equipment. You’ll be shocked how good the gear suddenly sounds. It’s not as dramatic going the other way around sometimes, but you can definitely hear the difference when a mediocre player goes from mediocre equipment to finely tuned studio gear.
When I was the musical director for for former Rolling Stone Mick Taylor for a tour, Mick didn’t travel with any gear, preferring to use what his fans could provide him at each town. He frequently played with some really big stinking heaps of crap gear, but every night he still sounded just like “Mick Taylor.” The gear never mattered.
The Room contributes about 20% to the overall sound. Even on close-miked instruments, the room is far more responsible for the final sound than many engineers realize.
The Mic Position contributes about 20% to the overall sound. Placement is really your acoustic EQ and is responsible for the instrument’s blend in the track.
The Mic Choice contributes about 10% to the overall sound. This is the last little bit that takes a good sound and makes it great.
If something doesn’t sound right, there are a lot of things to consider changing before you even think about twisting an EQ knob. Try the following in this order:
- Change the source, if possible (the instrument and/or amplifier you are miking)
- Change the mic placement
- Change the placement of the instrument in the room
- Change the mic
- Change the mic preamplifier
- Change the amount of compression and/or limiting (from none to a lot)
- Change the room (the actual room you are recording in)
- Change the player
- Come back and try it another day
Secrets Of Mic Placement
Bruce Sweiden (Michael Jackson’s engineer and widely acclaimed to be the “Godfather” of modern recording) says that mics are the voodoo magic of recording. Underground engineering guru Steve Albini says every mic has some place where it will sound best. But sometimes the search to find that place resembles questing for the Holy Grail if you’re just trying to pair a mic with an instrument.
Quickly finding a mic’s optimum position is perhaps the single most useful talent an engineer can have. You should always trust your ears and begin by listening to the musician in your studio, find a sweet spot and then begin your microphone placement there. If you don’t like the resultant sound, then move the mic or swap it with another. EQ is the last thing you should touch. If you can get the instrument to sound great without using any EQ, just imagine how fabulous it will sound when you tweak it a little later.
REMEMBER: Mics cannot effectively be placed by sight, which is a mistake that is all too easy to make (especially after seeing the examples in a book like my Recording Engineer’s Handbook). The best mic position cannot be predicted, it must be found.
How To Find The “Sweet Spot”
How do you find the ideal position to place the microphone on an instrument? This position is sometimes called the “sweet spot”, and it means different things to different engineers. For some, it’s the spot with the most balanced, natural sound. For others, it’s the spot that sounds larger than life, but not necessarily lifelike. Either way, finding it is actually a pretty simple process but surprisingly not taught that much. So here’s the simple way to find the sweet spot on virtually any instrument with any kind of microphone.
- To correctly place an omni-directional microphone, cover one ear and listen with the other. Move around the player or sound source until you find the spot that sounds best for your tastes and needs. Even though omni’s aren’t really used that much in modern recording (especially when you’re just learning), you’d be surprised at the results that you can get from them since they have a lot of positive properties (like no proximity effect and flat response). I was once consistently hired by a producer to record vocals because he loved the vocal sound I was getting for him. My secret - I always had the mic (an original Neumann U-87) switched to omni!
- To place a cardioid microphone, cover one ear and cup your hand behind the other and listen. Move around the player or sound source until you find the spot that sounds best. Your cupped ear simulates the way a directional mic hears. You’ll notice that the frequency response is altered somewhat, so keep in mind that’s usually what a directional mic is hearing as well.
- To place a stereo pair, cup hands behind both ears. Move around the player or sound source until you find the spot that sounds best.
Before you start swapping gear, know that the three most important factors in getting the sound you want are mic position, mic position and mic position.
Finding the sweet spot is certainly important, but there are a few other things that go into capturing sounds that will knock your socks off.
- The only reasons for close-miking are to avoid leakage into other mics so that the engineer can have more flexibility in balancing the ensemble in the mix. If at all possible, give the mic some distance from the source in order to let the sound develop, and be captured, naturally. As the brilliant engineer Eddie Kramer (Jimi Hendrix, KISS, etc.) always told me - “Distance Makes Depth.”
- Mics cannot effectively be placed by sight. The best mic position cannot be predicted, it must be found. It’s OK to start from a place that you know has worked in the past, but be prepared to experiment with the placement a bit since each instrument and situation is different. Probably the most important thing about mic placement is to know exactly why you’re placing it there. Start from scratch if you don’t know.
- If the room will the majority of the sound, start with the mics that pick up the room and then add close mics that act as support to the room mics. This is standard for recording a string section or an orchestra, and it works for other instruments as well. Unfortunately, most engineers usually work backwards, starting from the close mic and adding in the room mics. Try starting with the room mic first and you might be surprised just how well the instrument now fits in the track.
- To overcome phase problems, consider inserting an phase scope on your stereo bus. Leave it running all the time so your eyes and ears get in sync with what is in-phase and what is not. Monitoring phase this way does not guarantee good mic placement, but does allow bad placement to be spotted more easily.
- A huge sound is a larger than life sound. One way to capture a larger than life sound is by recording a sound that is softer than the recording will most likely be played back. Ever listen to the guitar sounds on Eric Clapton’s seminal recording of “Layla”? Both he and Duane Allman used little Fender Champ and Princeton Reverb amplifiers (the Champ is 6 watts into an 8” speaker and the Princton is 12 watts into a 10”) but the guitar sounds are huge. There’s currently a trend to using smaller amps in the studio (18 to 30 watts into a single or dual 10’s or 12’s, and the prized Ampeg B-15N bass amp is only 30 watts) and you just about never see anything larger than 50 watts because larger amps usually don’t record that well.
Phase Cancellation - The Destroyer Of Sounds
One of the most important and overlooked aspects of miking is making sure that the mics are all in-phase. This is really important because with only one out-of-phase mic, the recording will never sound right (especially the drum kit), and if not corrected before everything is mixed together, can never be fixed.
So just what is phase anyway? Without getting into a heavy explanation, it just means that all the microphones are pushing and pulling together. If one mic is pushing while another is pulling, they cancel each other out. Check out the diagram of Figure 1.
Figure 1 Two Microphones In-Phase
In this figure, both mics are pushing and pulling together. Their signal peaks happen at the same time as does their valleys. As a result, their signals reinforce one another.
Figure 2 Two Microphones Out-Of-Phase
In figure 2, when mic #1’s signal peaks, mic #2’s signal valleys. They cancel each other out and result in a very weak sounding signal when mixed together. This cancellation usually doesn’t happen at all frequencies, just in frequency areas from about 500 Hz down, but any cancellation is a bad thing.
Checking microphone phase should be one of the first things that an engineer does whenever more than a single mic is wired up and tested. This is especially the case in a tracking session where a lot of mics will be used, since having just one mic out of phase can cause uncorrectable sonic problems that will haunt the recording forever. A session that is in-phase will sound bigger and punchier while just a single out-of-phase mic will make the entire mix sound tiny and weak.
Acoustic Phase Cancellation
There are two types of phasing problems that can happen - acoustic and electronic. An acoustic phasing problem occurs when two mics are too close together and pick up the same signal at the same time, only one mic is picking it up slightly later than the first because it’s a little farther away (see Figure 3).
With acoustic phase problems, the sounds won’t cancel each other out completely, only at certain frequencies. This usually makes the sound of the two mixed together sound either hollow or just lack depth and bottom end.
The way to eliminate the problem is by moving mic 2 a little further away from mic 1, or if the mics are directional, make sure that each one is pointing directly at the source that they’re trying to capture. In the case of drums (where this pops up more than anywhere), keeping the mics parallel to each other, or at a 45° angle for mics underneath drums really makes a difference.
The 3 To 1 Principle
Moving the mics further away from each other than they are from the source is known as the 3 to 1 Principle, which is pretty important when considering any multi-mic setups because, if you observe the rule, you can stop any phase problems before they start. Simply put, the 3 to 1 principle states that in order to maintain phase integrity between microphones, for every unit of distance between the mic and its source, the distance between any other mics should be at least three times that distance. For instance, if a pair of microphones were placed over the sound board of a piano at a distance of 1 foot, the separation between the two mics should be at least 3 feet. If the distance from the source was 2 feet, the distance between mics should be at least 6 feet. (See Figure 4)
This principle is not a hard and fast rule but it certainly is a good guideline for eliminating acoustic phase problems. Remember, if you record something with a phase problem, no amount of EQ or processing afterwards can ever make it right
Electronic Phase Cancellation
Besides the problems of acoustic phase, you have to take a look at the electronic phasing of the mics as well.
Why would there be an electronic phase problem? Almost all of the time it’s because a mic cable was mis-wired, either repaired incorrectly or originally wired incorrectly from the factory (which is rare). I actually just had just such a problem pop up in a session at the world famous Village Recorders in Los Angeles, where the room was recently rebuilt, the console upgraded, and one of the inputs on the mic panel had it’s wiring reversed. If we weren’t diligent about checking this before the session started, we would’ve undoubtedly spent a lot of time trying to track down why things sounded so funny, and probably never would’ve even dreamed that a mic panel was wired backwards. There are two ways to check the electronic phase.
Checking Phase The Easy Way
Checking phase is essential on any instrument being miked with more than a single microphone, but the chances for an out-of-phase problem are far greater on the drum kit since it usually has more mics on it then any other instrument.
There’s a very easy way to check mic phase (although not as precise as method #2 shown later) and that’s by simply listening. The trick is to know what to listen for.
After you get a mix balance together, flip the phase selector on each mic channel one at a time either on your console or your DAW during playback. Whichever position has the most low end, leave it there. Do this on every mic in the session (select overhead and room mics in a pair, but check the left mic against the right as well), then check it against every other mic that you might be using in the session.
Understand that you will never have all microphones completely in-phase, but problems may be greatly diminished by reversing polarity on some of the channels. The only way to determine this is through experimentation and listening.
Remember: one position of the phase switch will always sounds fuller then the other.
Checking Phase The Slightly More Difficult Way
This method takes a bit more work, but you’ll know for sure if you have a mic cable that’s wired backwards since it checks the electronic phase (polarity is actually a better word in this case). Also, you really have to have another person with you to make this work. It’s a two-man operation.
- After the mics are set up, wired and checked, but not necessarily placed, pick one mic that can be easily moved. This can be a scratch vocal mic, a hat mic, guitar mic - it doesn’t matter as long as it works, sounds good to begin with (it’s not defective) and can move next to the farthest mic used in the session. This mic will become our “gold standard”.
- With the gold standard mic in hand, move it next to any other mic that you wish to test. Put both mics together so the capsules touch and speak into them from about a foot away (the distance isn’t critical). (See Figure 5)
- Bring up the faders on both mics so the audio level (not the fader position) is equal on both. Make sure that each mic is at the exact same volume level.
- Flip the phase of the mic under test (in this case, the kick mic) and choose the position that gives you the most low end.
- Repeat for all the other mics.
Remember, you’re not flipping the phase of the gold standard mic - only the one that you’re testing.
Do this to each microphone. Any channel that has it’s phase selector different from all the others has something mis-wired (either a cable or a mic panel). Make sure you mark it so you don’t have the same problem again!
Times When You Might Want The Phase Selector Reversed
There are times when you should definitely consider flipping the phase before you start mixing. As I said before, there may be some acoustic phase issues as well because a mic may be farther away than another yet it’s picking up the same source. In the following cases, the phase should be flipped to overcome an acoustic phase problem.
- An Under-Snare Mic - A mic used under the snare drum should just about always be flipped out-of-phase.
- Room Mics - Depending upon where they’re placed, how much room reflection they’re receiving, and the level that they’re used in the mix, sometimes the room mics sound a lot better if the phase is reversed.
- Overhead Mics In Extremely Rare Cases - Once again, it depends upon how high they’re placed above the kit, what kind of reflections they’re receiving and if they’re the main sound of the kit. On rare occasions it might sound better (meaning fuller) if the phase is flipped.
Make sure you always check phase in MONO on a single speaker! It will be a lot easier to hear the difference.
Remember that the Phase Switch on the mic preamp, DAW interface or console is really a polarity switch, which changes the phase by 180 degrees at all frequencies by swapping pins 2 and 3 of a balanced microphone line. It may get the problem frequencies closer to being in phase, or it may get them further away. It depends on what the problems are, and the placement of the mics.
Mic Placement Most Likely To Cause Problems:
- Mics that are facing each other (like on the opposite sides of a drum)
- Mics that are facing the floor (just angle them a bit)
- Mics that are pointing at one source where there is another much louder source nearby with its own mike
That’s a lot of detail on how to capture the biggest, fullest sounds, but it can all be summarized in four simple rules:
- Get the instrument to make the sound you want to record first. If you can’t hear it, you can’t record it. If the source doesn’t sound great first, neither will the recording.
- Use the cover-one-ear-and-listen technique as described above to find the best place to start experimenting with mic position.
- Be sure that the mics are acoustically and electronically in-phase. You cannot fix phase problems in the mix. Get it right or you’ll end up recording it again.
Position the mic and listen. Repeat as much as necessary.
Following these rules will get you great sounds regardless of the equipment you have to capture them. You’ll find more information on mic placement in my Recording Engineer’s Handbook and The Drum Recording Handbook.