Recording Sound - Experimentation!

The very best thing about recording sound is that you're not bound by what you can achieve. I've talked about quite a lot over the past few posts, regarding recording techniques and best practices. However, at no point was I trying so much at telling you what to do. This is more of a loose guide for recording techniques. I say loose, because you can pretty much do what you like, as long as it sounds good. The key is, it doesn't matter how you record it; if it sounds good, it IS good!

So to that end, always use your ears as well as your equipment. A good example of this is when it comes to the mixing stage and you're removing problematic frequencies: you can find the frequency graphically on your screen, but it's always best to fine tune which frequency by looking away from the screen and listening. Let your ears guide you! Mixing will come at a later stage though, this post is very much about recording - the first step in your sound journey.

The main consideration for experimentation is having the time. You won't have much time to experiment if you're on the set of something being filmed, or with the band in the studio, so make sure you take plenty of time to do it. Thankfully (aside from equipment and software cost/rental), it's free to record sounds. You can do it over and over to your hearts content. And if you don't have posh equipment, that's fine too! You can use whatever microphones you have to experiment, such as phones,  mp3 players, or even poundland PC microphones; my number one go-to when I started experimenting 5 or 6 years ago. Why not take advantage of that time and be a bit whacky? After all, the most famous of Sound Designers only found some very classic sounds by experimenting (a lot found by accident!).

Hitting Things

When I say hitting anything with
anything, I mean it.

The easiest way to experiment with recording is to hit things... with other things. You'll be surprised what hidden gems of sounds will come out of some household items when you hit them in the right way with the right item! And you can literally do it with anything; just point a microphone towards it and record.

For one of my final year modules at university, I actually do just that for a composition. The basis was, create a percussive or musical piece out of one or several ordinary objects. It was only when I came home one weekend that I had the idea of recording my brothers VW golf mkII! I was literally smacking things, winding windows up and down, slamming doors and the glove box, revving the engine. But the part that really sticks out for me was a spare exhaust part he had in the garage. It had a very bell like quality which was a lot more concise and 'singular' than I thought it would be. That is, there weren't any clashing frequencies that made it dissonant. So I suspended it from a guitar stand and whacked it with some drum sticks. Below is the entire piece I created for the module, and you'll hear the exhaust near the end, which is used as a bell/glockenspiel type instrument:


For all the sounds, including this particular one, I imported them into Kontakt 4 and used the built effects and loops to design the sound for the piece. The exhaust was the easiest really, just because I only had to detune it slightly to match middle-C, and the rest did itself. Love it when that happens!

Microphone Manoeuvring

Sometimes you can get a completely
different sound depending on the angle

This is where your possibilities for record become endless. I think the mistake a lot of people make when approaching the recording of a source is trying to get it in one position which sounds 'the best', and keeping it there for the entirety of the recording. Especially for sound design, I would always recommend trying at least a few different angles, more so for a source that is being recorded as a 'sound'; i.e. not a source being recorded to represent itself in music or film.

The item in the picture to the left is an electric can opener. Items like this are great for all sorts of clunks, machinery and a wide range of engine-type sounds. One may choose to record from a distance, which will exclude a lot of the lower frequency content and get that clunky small-machine type sound. However, if you put the microphone very close, you get a much deeper intimate sound, good for slowing down and using as ambience for a factory setting.

The below track contains several different clips of the can opener, recorded from different angles. As you'll hear, the sound changes can be quite dramatic, and would compliment many different applications of the sound. Below is a list (and illustration) of how each short clip was recorded:

1: From above, front.

2. From above, back.

3. From above, side. (Number 4
Was the mic in the same position
with the can opener pushed against
the mic stands leg)

5. Mic pushing activator down.

6. Mic pushed against back opening.

7. Mic pushed against side.

What really gets the experimenting going is when you combine this item with others to enhance the sound.

For example, placing the can opener on a wooden bench and then using a contact microphone to record the bench as the can opener is working, you get an aggressive bassy sound, because of the direct transfer of energy. Similarly, you can place it on a hollow structure made of wood or plastic, and record with a normal condenser inside; this should give a resonance to the sound.

This tool of sound was from
the Eden Project. Big boomy
sound!

Tubes are also a widely used item for changing the properties of an otherwise normal sound. Depending on it's size and shape, the sound will bounce around inside, which will exaggerate a certain frequency range. The smaller the tube, the higher the frequency. This is usually recorded from an open end.

You can also put a membrane on the end of a tube and attach items to this, which will create a unique resonant sound. The image to the right shows one such item, which has a long spring attached to a membrane on this tube (made of wood). The resultant sound, when the spring moves, is much like a rumbling thunder.

Sound tools like these are very useful if you're stuck on resources or time; they allow you to create sounds that would otherwise need to be taken from an SFX library, or need a lot of planning to record properly.

Below are 3 clips I recorded with the tube sound tool. The first clip uses the same microphone above: at the start, the mic is half way into the tube, and for the end of the clip, moved out but still facing the opening. The second clip is me pulling the spring tight against the edge of the tube, which is recorded from outside the opening and then inside. For the final clip, I found that shouting into the tube caused a spring reverb effect. However, due to the tubes resonance, you get some very interesting sounds at different pitches.

However, I digressed slightly from the original topic, but I thought it was worth noting.

Be Random!
Well, what else can I say? Just use your imagination! Seriously, the amount of times I came across a sound I needed by changing the angle an object was at, or rolling it on the ground, putting it inside something, submerging it in water, putting water inside it, putting my phone in developer mode to stick the vibrate on constantly and holding it against said item... You can literally do anything to get the sound you want!

Be Forth-Thinking
If you plan on using any of the sound you're experimenting with in a production, always always always think ahead about what the sound will be used for. If you're doing a film project that involves a lot of out-of-the-ordinary sounds, you'll more the likely have to slow down or speed up a lot of them, so record these sounds at a high sample rate (96kHz). This means the detail is retained when slowed down.

Also think about composite sounds. When creating a machine say, you won't usually have a single recording for it. You'll have layers, each creating different elements of the frequency content or components of the machine. For example, a bassy engine sound might come from the can opener. Then for movement, you may have a car starter motor ticking over and pitch shifted. Then for a robot-like voice, you can record your voice and play it back through a speaker, with the cone attached to a membrane on a metal tube, which will give it a metallic sound. See what I did there?

Conclusion: If you have a recording device, or microphone and interface, you have the tools to create endless sounds. Even with free software such as Audacity, you can pitch shift, speed up, slow down, apply EQ and multitrack to create and shape any sound you can possibly imagine. As long you let your ears guide you, the possibilities are endless. Go out there and capture some noise!

Next time, we'll get stuck into some simple post production bits - audio editing and optimising, simple EQ and making sure you get the most out of your raw sounds.

Alex.

Recording Sound - The Room, Mic Placement & Gain

So there's your sound source. What's the most effective way of going about recording it? Todays post will go into the details of how important it is to consider the room you're recording in, where to best place your microphone and what levels are appropriate for what you need to get out of the sound. As we've covered the different types of microphones (Mic Choice Part 1) as well as their respective polar patterns (Mic Choice Part 2), we can incorporate how these will affect our choices of distance, angle and gain levels.

So why can't I just record everything in my bedroom? Well... you can. There's nothing stopping you getting the most out of the sounds you need with a reasonable representation, which can be enhanced in post production. However, taking some simple steps to prepare your room, or choosing a room dependant on the source can improve your recording immensely. Below, I'll go over what you might use for the appropriate desired effect on your recordings.

Dampened and Clean - If you plan to go the route of a reflection/reverberant-less recording that will allow you to add any and all effects afterwards, you'll want to use a room that is smaller and with as little hard surface as possible. The most typical setup for a studio recording is to have a reasonably sized room (4l x 6b x 3.5h metres) that incorporates lots of foam tiling for sound absorption and texturing that would reflect sound in all directions (to reduce reflections and possible phasing on microphones). There's no reason you can't get this effect at home though. A bed duvet pinned against the length of a wall will provide a sufficient amount of dampening. Some even choose to keep egg cartons and line their walls with them, which also helps. The thing to remember, which even I've forgot to consider in the past, is your floor and ceiling. These reflect sound as much as walls, especially when you have a laminate flooring. The easiest way to resolve this is by having carpeted flooring and the means to pin a duvet or carpet-like material to the ceiling, as well as your walls. And if you're budget can take it, definitely invest in some high-density acoustic foam tiles - you can easily buy a pack of these from ebay for £35/$55 which would be sufficient for even a professional environment.

Reverberant - It may be the case that you want to record your source with some natural reverb, which is perfectly fine if you know that this is the desired effect for your production. As reverb has unlimited potential in sound and effect, it's good to play around with this if you haven't had experience before. I'll go over a few examples and what they might add to your recording.

Music: If you're a guitarist who wants to have a huge reverberant sound for a lead solo part, you might want to have your amp and mics in a large church-like hall. The time at which the sound reverberates is usually between a second or two, creating a large sustained sound. This can also be true if you want a large drum sound, but i'd advise to have at least a little dampening to control this; otherwise, the sound isn't as precise, which won't help in the mixing stage.

Sound for TV/Film: A lot of sound effects and dialogue in this instance are recorded in a dampened/clean studio. However, you may not be able to bring a church bell or a huge crowd into your tiny recording studio. Instead, you can record them in their natural environment, or one which will reflect (pun not intended) the scenario on the screen. As long you perform some test recordings to ensure it sounds fine, you can save some time in post-production (as well as some CPU power from those plugins!).

Let's now consider the source sound. Much like with microphone choice, you have to understand how your source is creating sound physically, in order to find the best placement and gain level. For example, if you're recording an acoustic guitar, there isn't a lot of physical movement in the air apart from the musicians hand moving up and down to strum the strings. On the other hand, when you're trying to record a vocal, there's a considerable amount of air moving around with the singer breathing, shouting, as well as the troublesome popping caused by 'b's and 'p's. If you don't know what I mean, just place your hand about 2" in front of your face and say "Barry and Peter": you should feel the air shoot out more on the 'b' and 'p'.

Another consideration, especially for music, is how it may hinder the musicians ability to play their instrument. The worst thing you could do for any musician is to place a microphone or stand in a position that would mean they aren't comfortable and therefore can't perform in what should be their top form. From personal experience, this means microphones on drums that I would catch with my sticks when moving around the kit, or stands behind me that I would catch with my elbow. In short, always consider the musicians needs before placing microphones to get what may technically be the best sound; if they aren't playing their best, you wouldn't get the best sound from them anyway.

Linking in with musicians, but not exclusively relating to them, the proximity effect is also something you would need to think about. I say linking in with musicians, because the proximity effect can add a sense of intimacy with a vocal or guitar. I won't go into too much detail (as it's quite complicated), but due to the physics involved with the diaphragm and the short distance between the source and the microphone, a bass boost occurs naturally. You can test this yourself: just get someone to say a few words into one of your ears a few feet away, and then have them say it up close to your ear - you should hear it. This is used a lot in music and movies to emphasise a voice, but it's really up to you what you want to use it for: after all, if you use it and don't need it, you can (for the most part) EQ out the effect in post production.

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General Microphone Placement: I think the best (and only) way to describe microphone placement is through several different examples. These examples will work around a single instrument or source, and then detail different scenarios in recording them:

Vocals / Voice Over
As mentioned briefly, the human voice is quite varied in terms of both dynamic range and frequency. The way to work out the best microphone placement and gain is what you'll be using it for.
Music: I would always try and go for a studio-type acoustically treated room and have the microphone set up at mouth level with your singer. Generally you want the mic to be around 6" away. However, you won't have to worry about distance too much as an engineer, because the singer will (or should) move back and forth depending on the volume and effect. As with the proximity effect discussed earlier, they may move in to about 2", or for very loud singing, they may choose to back up to 8-10". Gain wise, you'll want to get them to sing a few lines repeated at as loud a level as necessary for the song or section, making sure the pre-fade level is touching about -3dB. This gives plenty of head room for short loud bursts. You can also consider the polar pattern, which would probably be cardioid to avoid capturing the room tone, but if you do want this, use a figure-of-8 pattern to control it.
ADR (Automatic Dialogue Replacement): This one has always fascinated me. I must clarify what this is first: all ADR is recorded in the studio after filming (hence dialogue replacement); this is common practice in many films. Basically, a film set is usually very noisy and, even though the sound is usually recorded regardless, you wouldn't get a seamless transition between shots. So instead, they record dialogue afterwards in a studio which gives them more control. So in terms of mic positioning, you want to try and record it as if you we're listening to them in the scene. For example, if they happen to be very close to the screen, you want quite an intimate recording similar to vocals as described above. If they're stood in the middle of a room a few metres away from the camera, you want to record them from a few feet away, usually above them. To get a better idea of this, just check out some DVD extras of films: Lord of The Rings has a dedicated feature on sound, and animated films usually have a section devoted to ADR (although not as direct as recording technique).

Electric Guitar/Bass
If you're either a guitarist of bassist, these tricks are so easy for you to have a mess around with. Both are pretty much the same, but guitars amps tend to have a slightly more direct sound from the speaker.
Live: When you don't have much control over where the amp goes, you tend to have to put up with what you have (especially in smaller venues). If you can, try and have the speaker unit in a reasonably open space with the back exposed; otherwise, you'll get exaggerated peaks and troughs in the bass frequencies. However, the key to remember for live sound is that you will never have as much control as the studio; always concentrate on suiting the sound for the venue. So moving back to the guitar amp; if you have a single cone, place your dynamic mic facing towards the centre of the cone, either directly or at a slight angle. If you have a 4/6 speaker cab, pick a cone and mic it up the same way. After all, you'd expect the amp/cab to be doing most of the work.
Studio: Because you will have more control, you can be much more specific about your mic placement to change the sound to your needs. The best way to find the guitar sound you want is to work out where it will lie in the mix. Are you recording a rhythm part? Is it a scorching solo? Fat power chords? All of these encompass different microphone positioning, because moving the mic around the speaker cone can dramatically alter how the recording turns out. The centre of the cone is where you get a very precise sound because it's where the most movement occurs. On the other hand, the edge of the cone is where the least movement occurs, so you get a bassier rounder sound with less high frequency content. Therefore, if you want to record a rhythm guitar part for example, you'll want to keep the microphone away from the centre of the cone so it doesn't take all the attention in the mix. Similarly with a lead guitar part, you want to place it in the centre to capture as much of an intimate in-your-face sound as possible.

Loud One-Shots
This one isn't very specific, but describes basic technique for anything in the nature of loud sounds that could potentially cause distortion. One particular example is fireworks. They have a whizz and then a very loud short bang. I'd say record the firework from a normal distance (8-10m) and follow the firework with your microphone; swinging it upwards as it lifts off. Gain wise, I would recommend keeping it low for a test recording, check what level came out and then alter accordingly. If it was recorded right, you'll have a very quiet whizz and then the bang heading towards 0dB (ideally -0.5dB). If your recorder has a very low noise profile and there isn't too much back ground noise, you can use a transient designer to bring out the whizz and tail of the bang which will make it sound a lot sweeter. More on that in another post though!

Traffic/Public/Machinery
This all lies on the application you'd use it for. For sound and film (or music if you chose to include something like that), recording in stereo in the best way to go about it. If it's not the focus of the mix (which is usually the case), you can always get away with recording 2 mono tracks and summing them to stereo panned hard left and right. For games which would use point sources, you can either record in stereo and sum to mono/split the tracks, or record in mono. This is especially important for ambience which I'll detail in a later post when I get to game audio implementation in UDK.
Regardless of this, if it's background noise you want, try and record the sound from a distance. With the public, this is vital, as the listener is drawn to the human voice and a particularly apparent one will stick out like a soar thumb. Mic placement is pretty simple: just point it at the crowd; for gain, keep it at about -3dB so you get a healthy signal if possible. If you're pushing your recorder though, back it off a little to avoid a high noise floor, as you'll more than likely pull this sound down in the mix anyway. I'd also recommend a cardioid polar pattern, as hyper-cardioid may be too precise for a 'crowd' sound, where omni-directional wouldn't give you much control over what you were recording.

Conclusion: Microphone placement and gain is a bit of art in itself. You really have to be forward-thinking and reflective, based upon the image you're portraying or the overall mix. As long as you have a good plan, you should be able to make the right decisions. And before I forget, I would go over Drum mic placement and gain, but I think that's big enough for it's own post! So I'll leave it here for now.

Thank you very much if you've read this far, it was a big one today. Next time, we'll go over some experimental things and the endless possibilities of recording your sources! I'm rather excited about this one I must say...

Alex.