Microphone Selection and Placement
The first thing to be said here is that anything under $50 is garbage. Don’t buy it. It’ll sound awful or it’ll break in a week. I’ve been there. Let my wasted dollars be your gain and save up for something decent instead! Same goes for microphone cables. Anything under $10 is of questionable quality, but you don’t need to spend a fortune there.
If you first want to read up a bit on types of microphones and their polar patterns, here’s a guide from Sweetwater.
Microphone Types and Uses
Handheld Dynamic Mics
The first microphone I will mention is the Shure SM57 (around $100). This’ll work great on snare drums and guitar amps, as well as being a decent live vocal mic. The Shure SM58 is basically the same microphone but with a windscreen. If you’re buying just one mic for now, I’d opt for the SM57 first as it’ll be more versatile. The SM57 is also a microphone that you can beat the heck out of and expect it to work for you every time.
The Shure SM57 is a dynamic, cardioid pattern mic. Dynamic means it doesn’t require phantom power and cardioid means it pretty much only picks up sound from in front of the microphone.
The SM-57/58 are a stage vocal standard as they have low handling noise and low sibilance. Not the best sounding microphone out there, but very forgiving. Not ideal for most acoustic instruments, though they’re commonly used on snare drums and guitar cabs.
Broadcast Standard Dynamic Microphones
Attn: Hangout On Air Show Hosts! These are the types of microphones you’ll want to be using when running Hangouts On Air. They are all cardioid pattern dynamic microphones and fixtures of the broadcast industry. They don’t need phantom power but they still require an outboard microphone preamp or mixer to get the proper amount of gain.
The broadcast industry standards are as follows:
Yes, they’re a bit pricey but they’re professional grade equipment and well worth the investment.
These mics aren’t strictly for speaking voice though. The Shure SM7B is also a great vocal mic, especially for singers who really belt it out. Michael Jackson used the original version, the SM7, for his vocals on Thriller. The Sennheiser MD 421 is often used on guitar amps and drums.
Large Diaphragm Condenser
Large Diaphragm Condenser (LDC) microphones are the most common type of microphones used for recording vocals in studio. They are higher in sensitivity and lower in self-noise than their small diaphragm (SDC) cousins, though their treble extension is not as great.
LDCs are highly directional in the upper-mid to treble frequencies, which means that on axis sounds such as singing directly into the microphone have greater presence.
Aside from vocals, LDCs are also used on instruments of all kinds, though they’re not as widely used for stereo recording as SDCs.
The Studio Project B1 microphone ($120) is regarded as a great budget mic for recording vocals and acoustic guitar. It’s a cardioid only microphone, so it’s not going to sound overly spacious or pick up room ambience, but it’s a step up in sound quality from a handheld dynamic.
The Studio Projects B3 ($160) is a similar microphone but offers 3 different polar patterns for just a slightly larger investment. Variable polar patterns makes this microphone more versatile. The Omnidirectional pattern, while picking up more room noise, produces a more natural sound on acoustic instruments.
I personally own the Studio Projects T3, which is SP’s flagship tube powered condenser microphone. It also offers variable polar patterns but has several steps in between Omni, Cardioid and Figure-8. These usually retail for $500 but with a careful shopping around you can find them cheaper. I use this microphone for vocals and acoustic guitar. If I had other instruments, I would use it on them too. Fantastic mic.
Small Diaphragm Condenser
Small diaphragm condenser (SDC) microphones are used in many different kinds of stereo recording arrangements.
Though not as sensitive as LDCs (and thus higher in self-noise), their frequency response typically extends higher into the treble range than LDCs. They also do not have the directional bump to the upper frequencies which would be problematic in stereo recording.
SDCs have quicker transient response due to the lower mass of the capsule as compared to LDCs. Transient response has to do with how a microphone handles rapidly changing levels in sound waves.
Unlike speakers, bigger doesn’t mean more bass. SDCs have the same bass capabilities as LDCs.
USB microphones provide a good starting point if you’ve got one already, but they’re not ideal because the upgrade potential is nil.
The biggest problem is that they’re incompatible with…well, audio equipment. For plugging straight into the computer for doing podcasting, nothing wrong with that.
When you’re recording music though, at some point you’re going to want to invest in a mixer and interface, maybe some outboard effects, which utilize balanced XLR and TRS connections. The XLR type connector for microphones and other balanced connectors has been around for more than half a century. If you buy a microphone made 30 years ago you’ll be able to plug it into a brand new mixing board.
Will you have equipment in ten years that will accept (and have driver support for) a USB microphone made today? Will the onboard USB interface even last that long? Is it easily repairable?
XLR microphones are future proof and will work fine with any audio equipment you invest in down the road.
Microphone Polar Patterns
There are three main types of microphones polar patterns. The polar pattern of a microphones determines from which directions a microphone will pick up sound, and its response on-axis (direct) or off-axis (indirect) sound sources.
- Bi-Directional (Figure-8)
Cardioid microphones have what is known as proximity effect, which means that the bass response increases as you get closer to the microphone. This can be leveraged to thicken up thinner sounding vocals.
Most handheld microphones feature cardioid capsules for the off-axis rejection needed for stage performances, though they are common in studio LDC and SDC microphones as well.
There are different types of cardioid patterns aside from the standard: Supercardioid and Hypercardioid. Both have an even narrower front pickup pattern than the standard cardioid which means greater off-axis rejection and possibly less feedback. The caveat is that super/hypercardioid microphones require more care in placement to prevent fall off, especially with vocals. Unlike the standard cardioid pattern, they do pick up a bit of sound from the rear though not as much as Figure-8 or Omni-Directional mics do.
Bi-Directional, or Figure-8, microphones pick up sound from the front and rear, while rejecting sound from the side. Figure-8 mics are used in Blumlein and Mid-Side stereo arrays, among others.
Figure-8 mics have even greater proximity effect than cardioids.
Omni-Directional microphones pick up sound from all directions. This isn’t to say that omnis are surround sound capable. Two or more microphones are required to get left/right and front/back spacial imaging.
Unlike the other two polar patterns, omnis do not suffer (or benefit depending on the application) from proximity effect.
Check out the HomeRecording.com Microphone Guide for more info on purchasing mics for various instruments.
For acoustic guitars, assuming you’re not using a pickup system, you’ll want to place a single condenser microphone about a foot and a half away, level with the fretboard and pointing at where the neck joins the body or thereabouts. Here’s a good article on various mic techniques for acoustic guitar.
For vocals with a condenser, you’ll want the mic about a foot away. Remember with cardioid pattern mics that the closer you get to the capsule the more “proximity effect” comes into play. If you get too close to the mic your vocals will be way too bassy. For reference, think about how radio DJ’s sound on the air and that’s proximity effect in action. You also need to be really, really careful with your “plosives” and sibilance when close micing vocals. Those pops of the P, hiss of the T and S etc. Pop filters help with this, but the best solution is more vocal practice.
With a handheld dynamic, you need to be a couple of inches away. Don’t eat the mic.
Regardless of what type of microphone you’re using for vocals, you need to work the mic when your voice gets louder or softer. In other words, control your level by getting closer or farther away from the mic. Don’t expect a compressor to do the work for you.
Instrument and Vocals
You can actually pick up an instrument and vocal pretty well with a single omindirectional microphone if you’re careful. This is the way I do it, for now. For closer micing, place the microphone upside down about a foot or so away from your mouth. You can also try placing the microphone about two feet away but positioned at chest level.
Stereo Mic Arrangements
Whether you choose to mic an instrument in stereo or mono depends on where that instrument sits in the mix. In a louder, more dense mix, stereo micing often isn’t necessary (except for piano). But, in a more sparse mix with very few instruments, stereo micing can add great realism to your sound. Acoustic ensembles may also benefit from using a stereo arrangement to pick up the room sound.
An X-Y setup requires a matched pair of microphones, with identical mic preamps and gain settings for optimal imaging. Without careful matching a lopsided or otherwise disfigured stereo image results.
In mixing an X-Y setup, you would pan each microphone hard left and right, or near to it.
The Rode NT4 is an example of a SDC stereo microphone that is built specifically for X-Y micing.
When using two microphones, you’ll need something called a stereo bar. The one pictured below is the size you’ll want for doing X-Y micing.
Due to the coincidence of the microphone capsules, sounds arrive at both mics nearly simultaneously which essentially eliminates phase issues. X-Y has great mono compatibility because of this.
An alternative to the X-Y stereo technique is the Blumlein method. This uses the same arrangement as X-Y where the microphone capsules are angled at about 90 degrees to one another, but using Figure-8 (Bi-Directional) microphones instead of Cardioid.
Most Figure-8 capable microphones are large diaphragm condensers which, being side-address, means the microphones must be placed one atop the other (one of them upside down) with the grilles touching.
Blumlein affords you better spacial imaging and ambiance at the cost of picking up more room noise, so this arrangement is better suited to locations where ambient noise wont overwhelm the primary sound source.
Blumlein is one of many options suitable for recording grand piano. It also has very good mono compatibility. Blumlein can be used to record individual instruments or to provide wider reinforcement to an ensemble.
Mid-side utilizes a cardioid mic pointed forwards and a figure-8 pointed sideways so that the capsule faces are perpendicular to the sound source. Though mid-side uses two microphones it requires three channels on your mixer or DAW to work. The figure-8 microphone is routed through two channels, panned hard left and right, where one channel’s phase is reversed.
You can adjust the width of the stereo image by increasing or decreasing the level of the figure-8 channels relative to that of the cardioid. More signal on the figure-8 makes for wider stereo, and vice versa. The microphones must be setup one atop the other, as with the Blumlein method.
Mid-side is fully mono compatible.
Jecklin Disc uses two small diaphragm omnis angled approximately 20 degrees outwards from one another with a sound absorbing disc in between. This arrangement is designed to mimic natural human hearing and as such can provide incredibly realistic imaging.
Unlike Binaural (dummy head) recording, Jecklin setups provide a useful stereo image when conveyed over loudspeakers whereas the former is really only good for headphones.
Often used for room reinforcement for ensembles or placement near the hammers over the soundboard of a piano.
Spaced pairs can suffer from phase issues which results in frequencies being cancelled out when folded down to mono.
But that’s not all…
These are just a few of many techniques for stereo recording. If you’d like to learn more, here’s a nice PDF Guide on different stereo and surround micing techniques.
Micing a Whole Band?
I’m a singer and guitarist, so I’ve only read about micing up a drum kit. That’s a really tricky subject. For Hangouts, all I can say is that you’ll want to attack this from a “live sound” standpoint. The very least you can do is throw up a pair of condensers as stereo overheads. It’ll work alright for a laid back jazz drummer but not a rock drummer. You’ll also need a kick drum mic, snare mic (SM57, probably) and a few others depending on your drum setup. Don’t even ask me about EQing for drums! I’m not an authority on drum sound reinforcment, so if you can point me towards good sources for this info I’d like to have a link to it here. Here’s a link to an article from Drum! Magazine on choosing drum mics for live sound.
Keyboards and Bass
Keyboards and Bass are easy becauase you can just run them through a DI box (like the Radial J48) and into the board. Keyboard players and bassists really ought to have good DI boxes as part of their kit. A little amp modeler and a DI box is a great backup option for guitarists too.
Electric guitar? Stick an SM57 (or 58) in front of the cab. Experiment with the angle of the mic and which part of the speaker cone you aim it at. Use your ears and your discretion to find what sounds best. Half the fun is in experimenting with this stuff.
I recommend the SM57 because most people have already got one. By no means is this the only microphone for the job or the best one for your setup.
For vocals, any good quality handheld dynamic mic will do just fine. I’d avoid using a foam windscreen though because you’ll take the already rolled-off treble and muffle it even more. You don’t want your vocals to be so muddy sounding they’re unintelligible. Condenser mics are usually a poor choice for vocals in a live band situation because they’ll get too much bleed from the other instruments, though there are cardioid condenser mics out there designed for stage usage like the Neumann KMS 104.
Next: Mixdown: Getting your Levels Right