How to Record Clean Vocals? Part 2.
PART 2: THE MICS AND THE VOCALISTS
Alright so we've covered how the most important part of getting a clean recording at home, and hopefully you've read that and followed that advice. If not, go read it and come back. Ok, done? Great, sit down and let me tell you about the Mics and the Vocalists (or anything else you are trying to record).
I'll focus on tips for recording vocals, but really this goes in a general sense for everything. As far as mics go you have a ton of options, but let's narrow this down so we can talk about the types of microphones you might have and then you can use which ever one you want. Microphones come in different types based on two things: transducer design, and polar pattern. You have three types of transducers: dynamics, ribbons, and condensers, and three main types of polar patterns (with some variations): cardioid, figure-8 or bi-polar, and omni-directional.
Most of the time, microphones that are used for vocals are going to be cardioid, often referred to as a directional microphone. This is mostly true, but cardioid mics will also pickup sound from the sides. Yes some will have a tighter pickup pattern than others, but you can also have wider patterns. You can have super or hyper cardioid variations, and ultra-cardioid/shotgun mics also fall into the cardioid category. In general, a cardioid microphone will pickup what it's pointing at, and reject sound from the rear. A figure-8 or bi-polar microphone, will pickup both front and back but reject from the sides. You typically find this with ribbon microphones and some condensers as well. The reason for calling it a figure-8, is that on a sensitivity chart, it looks like an 8. Bamm, blew your mind right? Not everything in audio is complicated. And lastly we have omni-directional, which you guessed it, pickups everything all around it. Fun fact, all dynamic microphones are inherently omni-directional, and it is only through clever use of what is called a “sound maze” that engineers have managed to cause sound coming from the rear of the mic to phase cancel itself before hitting the diaphragm. This is also why you should never cup the mic, because your hand will negate this clever design and return it to a more omni pickup pattern and give you mad feedback.
Now for transducers. Dynamics are essentially a magnet suspended inside a wire coil, and when the magnet moves it generates current because of electro-magnetism. These constructions are relatively heavy, and take more SPL to move. They also do a very good job of handling high SPL sources. Fun fact #2 the Shure SM57/58 was designed for presidential speeches because you could fire a gun right next to it and it would still work just fine.
Ribbons on the other hand are much more delicate. These mics use an extremely thin sheet of metal, suspended between two magnets. These transducers are much lighter than dynamics and therefore have a better transient response, and are also known for having a sweet sounding top end. These can sound really good on any number of acoustic sources, including vocals. Ribbons are inherently figure-8 mics because sound coming from the side of the ribbon doesn't cause it to move back and forth in it's suspension, so it doesn't create any signal. These will pickup more of your room than a cardioid mic because they are about equally sensitive from the rear as they are from the front, so your reflections will have an easy time getting in. So if your room sounds bad, maybe don't use a ribbon or figure-8 pattern. The other thing to consider with ribbon mics is that they can be damaged more easily by high SPL sources than dynamics and condensers (especially vintage ones if you are lucky enough to have them.)
And lastly, it seems to be everyone's favourite, condensers. These transducers are made up of a back plate and a diaphragm which form a capacitor. When the capacitor holds a charge (usually powered by phantom power), air pressure will move the diaphragm closer to or further away from the back plate which creates the voltage that is our sound signal. You can also add a second diaphragm behind the back plate and change the charge of the second diaphragm to change the polar pattern of the mic. These mics tend to be highly sensitive to sound, but are not generally as delicate as ribbon mics. They also sound good on a number of sources.
OK, so now we know what our mics are made of, and how they pickup sound. So what does that all mean? Most likely, you will want a mic that has a tight cardioid pickup pattern, or at least has high rejection characteristics. But honestly, just pick your favourite. Go put that mic into the booth we created in part 1 and make sure that it's point at the absorption (remember our flashlight analogy from last time). Put the mic on stand, and make sure that one of the feet of the stand in pointing in the same direction that boom is pointing so that the mic won't tip the stand over as easily. You want the diaphragm of the mic to be approximately mouth height of your singer so they don't have to tilt their head to sing into it. You can also adjust the sound you're getting from the mic by aiming the mic slightly higher or lower than the singers mouth if you want to emphasize certain aspects of their sound. Turning the microphone off-axis a little (to either side) can also be useful if you have a very essy singer. Now that the mic is aimed how you want it, you'll want to put a pop filter on it (unless it's an SM7b which has it built in). If you're mic is pointed off-axis, your singer will consciously or unconsciously try to turn themselves to be on axis again, so place your pop filter in relation to where you want them sing. Make it a target for them. Lastly, you will want at least 20cm of distance from the singer to the mic, but you can experiment with moving further back or closer to the mic for different tones. Generally, closer will give you more bass response and sound more intimate, and further away will be the opposite. This really depends on a lot of things that are very individual to the singer.
That's enough about mics. I'm sure many of you are bored by this point and thinking “but I already know how to set up a mic” (Did you make sure it's plugged in? Did you turn on phantom? Turn up the gain?). But how do you set up your vocalist? These tips are good even if you're recording yourself. Getting a good vocal performance is the most important part of recording the vocals. If you don't get a good performance, the rest of this series will not matter in the slightest! Seriously, Adele used her vocals from a home recording when she was doing a demo instead of the version from the professional studio because the performance was that much better. Think it was Rolling in the Deep or that hello song, but I could be wrong, I don't feel like looking it up.
So, first the environment. Most people don't like being stared at while they sing, especially in a studio setting. It can be really off putting to have a whole band, plus an engineer watching you sing. Think about it, all those people, watching you, depending on you, judging you! Not fun. So, kick everyone else out if you only have one room, and turn down the lights. If you have a dimmer, that's great, but make sure your mic isn't picking up noise from it (this can happen with condensers especially). If not, turn off the overhead lights and try a lamp, or natural light from a window can be good too. You warm, soft light, so at least they can't see you judging them. The little vocal booth you built will also help them feel like they have a little privacy so they can be more comfortable. If you have one available, a stool (with no back so they don't slouch) can also be good so they have a spot to rest. Also grab a couple music stands, one for holding lyrics and writing notes, and one for their other odds and ends. If you have a small piece of carpet for the second one that's great, but a small towel will also help keep the noise down. You also want to have some beverages on hand, namely water and some herbal tea. The water should not be cold, it should be room temperature or warm. Cold water can tighten the throat and vocal chords which is not conducive to a nice vocal sound. Tea is tricky, because caffeinated beverages are also not great for singing, so stick to herbal tea. Chamomile and Lemon tea are generally good bets, but if they ask for black tea or coffee, just give it to them. Remember it's about making them comfortable.
Ok this is getting really long, so I'll cut it here. Next time we will talk about the rest of the recording chain, and maybe I'll address any questions that come up in the comments of this post.
Happy Recording and Mixing!