Improve Your Recording

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Revision as of 21:38, 13 March 2012 by CliveCatterall (talk | contribs) (link to portable vocal booth page added)
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Below you will find some advice about how to improve your recording. The page is separated into two sections: Technical, which deals with recording set-ups, common problems, and editing solutions; and Style, which discusses reading techniques to help you improve your reading style. Please feel free to add any hints & suggestions to this page.

Technical

This section covers specific problems and solutions for technical issues in your recording.

Plosives: popping P's

A common problem with audio recordings is the "exploding p," called a plosive, sounds which create a pop in the microphone. Usually plosives are created by the letter "p," but "t," and "s" and other letters can be problematic as well. Here are some solutions:

  • Use a foam shield (which you can buy at electronics stores)
  • Make your own shield out of a hanger & a nylon stocking (!)
  • Read into the microphone at an angle, or "past" the mic, instead of into it. (i.e. instead of positioning your mouth so that when you breath out the air rushes straight at the microphone, position you mouth so that you are at an angle from the microphone and your breath blows across the top or to the side of the mic, and NOT directly at it.).
  • If you're using a headset mic, put the mike down below your chin, or above your nose.

Sibilants: harsh Ssss

Some readers find that they have problems with very harsh and loud S sounds. This problem does not respond well to shields or microphone angles, but there are a couple of things you can do:

  • Move a desktop microphone further away The S sounds are only loud quite close to your mouth. If you record between 4" and 8" away from the mouth the S sounds should be reduced. Note that this can introduce unwanted room echo. See below.
  • Use a De-Esser This is a special audio compression program that targets this problem. There are Plug-Ins that you can download for Audacity that do this.
  • Use an Equaliser An Equaliser is like a fancy tone control, and is built into Audacity already. You can only use an Equaliser if the problem is a fault in your microphone that makes it is too sensitive to the S sounds. Electret microphones often need an equaliser to help them produce a good sound.

Variations in loudness and voice tone

The most common reason for a recording to vary in loudness is that the reader is unconsciously swaying or moving about while reading, often because the reader is so caught up in the story that they forget to keep still. This type of reader can produce and absolutely captivating recording, but unfortunately both loudness and voice tone are very sensitive to the distance between the mouth and microphone.

Setting the microphone a little bit further away from the mouth can help to reduce variation, as slight movements will make less difference.

Although standing while recording is very good for breathing, it does make it very difficult to control the exact distance to the microphone. Most readers find that it is better to find a compromise seating position where swaying is controlled but the body is still upright, perhaps on the front edge of a chair so the knees can be slightly below the hips to help with breathing. However, one reader has reported that he likes to read in an armchair so he can rest the back of his head against the seat to control its position relative to the microphone.

A second, less common reason for tone and loudness variation is comes from recording with the microphone places slightly off to one side in an attempt to reduce popping sounds from problem consonants, such as Ps and Ts. Voice tone is very sensitive to the way the mouth is pointing relative to the microphone as well as the distance. The most natural tone is produced with the mouth pointing directly at the microphone. As you position the microphone off to one side, above or below the mouth (known as "off-axis" positioning) you pick up fewer high frequency sounds and the voice sounds less bright, eventually sounding dull and muddy. These high frequency sounds are very important to the understanding of speech, so it is important to control the off-axis positioning as well as you can. It is easier to control the angle of the mouth relative to the microphone if you place the microphone above or below the mouth rather than to one side. This way you record facing towards the microphone but keep your head level. This is much easier than trying to maintain some imaginary angle between your mouth and the microphone so your breath passes just to one side.

Probably the best solution is to use a pop filter. A pop filter is made from a very fine mesh material stretched over a metal frame. The filter allows sound to pass through, but it blocks the tiny blasts of air produced by Ps and Ts. With a pop filter in front of the microphone you can record "on-axis" and get the best and most repeatable voice tone. If you mount the pop filter about 7" away from the microphone you can speak with your mouth right up against the filter, making it much easier to keep a constant distance between your mouth and the microphone. If the mesh is very fine and the mounting separate from the microphone you can even speak with your lips lightly brushing the filter material itself.

Variation in loudness and tone between recording sessions

Again, assuming that you have set the recording levels the same and are using the same microphone, the most likely cause of loudness and tone change is variation in the distance and direction of the mouth relative to the microphone. As in the section above, the most reliable solution is to use a pop filter mounted at a fixed distance from the microphone to help you to maintain distance and direction.

If you do not want to use a pop filter you could consider measuring the distance between your mouth and the microphone at the start of each recording session. If I stretch out my hand the distance between the tip of my thumb and the tip of my little finger (pinkie) is about 9". I put the tip of my thumb against my lips and shuffle my chair and microphone stand until the tip of my little finger rests against the microphone. If you watch the opening scene of the film "The King's Speech" you can see the actor Adrian Scarborough playing the part of a BBC announcer making elaborate preparations before speaking on the radio. Just before he speaks he checks the distance between his mouth and the microphone in just this way (though he uses two hands and so has a much larger distance than I use).

If you are using a mouth to microphone distance of 6" or more you will be picking up a significant amount of sound that has been reflected around your room (Room Echo). The reflected sound will be different in different rooms and even at different places within one room, so try to record from the same place every session. Keep windows and doors in the same position for each session, as these can alter the reflected sound as well.

Room Echo

Unless you are lucky enough to own a recording studio, all of your voice recordings are going to contain a small amount of room echo. If you are using a mouth to microphone distance of 6" or more your recordings will contain enough room echo to make it a significant part of the overall sound.

This means that however good your microphone is, your recordings aren't going to be the best unless you sort out the sound of your recording space. The good news is that speech recording is much simpler than music recording; all we need to do is try to make the room reflect as little sound as possible. The simplest way to do this is to choose a room in your house that has a carpet, curtains and big pieces of soft furniture. Bedrooms are usually a good choice. The fabric, carpet and padding all absorb sound and make the room sound more "dead".

You can get an idea what the likely difference in recorded sound will be by listening to the audio clip kitchen_and_bedroom. The same microphone is used to record the same text in a kitchen with hard floors and walls and in a bedroom with carpet and curtains. The audio clips recorded in the kitchen are first followed by the same clip recorded in the bedroom.

You can also experiment to find which rooms are going to be good for recording by listening to the echo in the room after you clap your hands together loudly. A kitchen with a hard floors and no soft furnishings will usually have a more echoey sound than a carpeted bedroom for example. However, you can probably find somewhere in your house that will have so little echo that you can record there and produce a good audiobook sound.

In most ordinary houses the rooms are too small to hear a sharp sound (like hands clapping) separate from its echo. The echo arrives so quickly from the reflecting wall that we don't hear a gap and the sound and echo merge. What we do hear is a ringing sound as the echo reflects multiple times around the room. If the room contains soft furnishings, curtains and a carpet a lot of the sound energy is absorbed in each reflection and the ringing dies away very quickly. Hard surfaces, like doors, ceilings, windows and hard uncovered walls will reflect sound with only a small loss of power. This is why opening doors and windows can sometimes improve the room echo: the sound passes through the doorway and is absorbed by the space beyond. This is also why the room echo can vary so much within a room: rooms are rarely symmetrical - in one position there may be a direct path to a reflective wall and in another there may be an open doorway or a large piece of soft furniture in the way.

The best way to find a good place to record is to walk around all of the rooms in your house clapping your hands and listening to the ringing sound after the sharp clap. You will quickly find the room with the shortest ring - probably one of the bedrooms. Walk slowly around the room and find the place in the room with the shortest ring. In doing so you will probably notice the difference in sound when you are close to a wall, that internal room corners are very strong reflectors of sound, and that in some places you can get "flutter" echo (usually where there are hard walls exactly parallel to one another).

If you cannot find anywhere with a really short ring try closing curtains, and opening doors and windows (if that doesn't introduce more noise!). If that doesn't work you will have to try hanging up blankets and duvets on the walls or over drying racks to try and reduce the echo.

If you are still stuck you could consider building a cheap portable sound booth. There are instructions here.[1]

Background Noise

  • Get the right equipment. The best choice for a mic is something that plugs into your USB port. This means that the audio goes straight through to your computer. The alternative is to have a mic that plugs into the microphone input, which relies on your sound card. If you have a medium or poor quality soundcard, you probably won't get the best audio quality with a non-USB microphone.
  • Set the volume first. Make sure that the final recording isn't so quiet that you need to increase the volume after you've recorded. Increasing the volume after you recorded will make any background fuzz you have much more noticeable. Try this on your own set up. Turn the input volume down for your microphone (either in your software, or through the computer's settings) and record something short. Then change the volume back to the normal volume and record the same thing. Adjust the first recording so that it is at the same volume as the second recording. Hear the difference in background noise?
  • Turn off noisy appliances. Washing machines, dishwashers, central heating pumps and boilers etc. can all contribute noise to your recording, even when they are several rooms away. Pause or switch them off while you record.
  • Block fan noise. Fan noise is a problem to anyone who records directly into a computer. Try to put a barrier between the computer and the microphone. If you record with the microphone on a tabletop put the computer under the table. Alternatively make a wall of pillows and cushions or use a sofa and put the computer behind it as far away as the microphone cable will reach. Both of these methods limit the fan noise reaching the microphone directly, and the noise must be reflected first (which reduces the loudness of the noise).
  • Some consistent background noise can be effectively removed. Audacity software versions 1.2.6 and lower do not do a very good job of noise removel. They tend to sound tinny. Version 1.3 and higher provide more satisfactory results. While there are programs and techniques which can make "noisy" recordings sound better, it is always much better to work at ways to cut down on noise before you read. If you need after recording help, visit the Advice forums for ideas, or create a post there for noise removal. There is also a Noise Cleaning page which explains the use of various software programs.

Style

The key to developing a good reading style is to become comfortable with your reading. Let your body relax as you're reading, and don't get frustrated over mistakes. If you are tense you're more likely to read too quickly, or forget to enunciate words. Don't worry about reading too slowly, because listeners will prefer a slightly slower reader. This allows them to digest what they are hearing and enjoy it more. You will usually make fewer mistakes if you are reading more slowly too.

If you find that you are making a lot of mistakes (and if this bothers you - you could always edit them out later) try reading the text aloud just before you record. Rehearsing the text like this allows you to relax and not worry so much about any stumbles you do make. It is important that you do read aloud when rehearsing - it forces you to read every word and only then will you discover the unfamiliar combinations of words that can cause stumbles.

Voice

Some use nasal sprays, mint-drops, brushing their teeth and chamomile tea, to clear the throat, to be able to breath well and also to get rid of "mouth-noise", these little clicking noises the tongue may produce. A wide and clear nasal passage and throat gives your voice more timbre.

To speak without gasping for breath every few words you need to be able to breathe freely. Wind instrument players and actors stand or sit with a straight back to allow as much air into their lungs as possible. You may also find sitting right at the front of your chair helps breathing.

If you want to record the most brilliant, deep, resonating voice you can do, (unless you are reading a shady, muffled speaking character *wink*) try looking slightly upwards while you are reading. Just like singers do it in the recording studio. Just like radio moderators have their mic slightly above them. Of course it's not easy to hold your script very long there but if you like the effect, hopefully you will find a way to keep it there.

Voice Characterizations

Using different voices in dialog is certainly not necessary in your recordings. It may even be better to avoid them in certain circumstances. However, some people will want to create different voices for different characters in a story. The following is a thread in which several volunteers have discussed ways to develop and improve upon this skill. Voice Characterizations and for more, see the Voice Character Performance page.

There is also the excellent Storyteller's Recording Guide.