Equipment - a guide to recording oral history

Equipment

It is vital that oral history recordings are of the best possible quality. You want to produce interviews that can be clearly heard and understood for listening and transcribing. You also owe your interviewee the respect of producing the best recording you can.

An oral history interview that is virtually inaudible because poor equipment has been used is useless; you will have wasted time and money. Buy, hire or borrow the best equipment that you are able to.

Digital or analogue?

You can choose between digital and analogue recording equipment. There is considerable discussion among professional oral historians about the pros and cons of these two recording methods, and both are used extensively.

Digital recordings are not necessarily better than analogue recordings. A good quality tape recording is better than a second-rate digital one. With both kinds of equipment you will need to be aware of the following important considerations.

Digital recording equipment

Key points to remember

Minimum recording requirements for all digital media, including computers are:

• 44.1 kHz – minimum sampling rate
• 16 bit – minimum bit depth

If you are unsure of the capacity of your digital recorder, check your equipment manual or ask a technician.

• Not all digital recorders are suitable for oral history. Avoid those that use proprietary software, for example 'personal recorders' that create files that can only be used with the manufacturer's software. You are dependent on such software for listening to the sound and copying it.
• Keep the raw material from a digital oral history recording for archiving exactly as you have recorded it. Do not edit or attempt to enhance in any way before offering it to an archive. Authenticity is vital.

Mini Disc

• Professional sound archivists do not recommend buying Mini Disc for making original recordings. While the sound recorded appears to be acceptable it uses a coding system that can cause a loss of data in further copying of the material.
• If recording on a Mini Disc, use the standard play setting, not one of the long-play options.

DAT

• DAT recorders use a cassette format for making digital recordings. While these recorders have been widely used in the field, they are now becoming obsolete as other non-tape-based digital formats replace them.

Note: If you already have one of these recording devices, check the minimum recording requirements for oral history.

Portable hard disk recorder

• These recorders are capable of producing a high quality recording in a file format (see below) on a compact flash card or portable hard drive.

Copying digitally recorded interviews for an archive

• Sound archives prefer to receive the raw, original recording if possible. Keep copies for your own use.
• To preserve material for the future, you need to use standard formats that computer systems recognise. Those preferred are:
  • .wav
  • BWF
  • AIFF.
• For Mini Disc, DAT or hard disk recorders (i.e., those that record digitally to a hard drive or some kind of removable memory), burn the recording onto a CD using one of the above preferred file types. Do not email these recordings to an archive as MP3.
• For material recorded directly onto a computer hard drive, archives will accept either data or audio CDs.

If you have any queries about the suitability of your digital equipment for recording oral history or how best to send your interviews for appraisal to an archive, contact Alison Parr alison.parr@mch.govt.nz, telephone 04 496 6331.

Tape (analogue) recording

Key points to remember

• If you buy equipment, the size of your budget will determine its quality. Ideally, a professional-quality tape recorder with an external microphone and high-quality cassettes should be used.
• If you have a suitable tape recorder that has not been used for a while, take it to a technician for a maintenance check.

Features to look for in a tape recorder:

• controls that allow you to play the tape (PLAY), wind back the tape (REWIND), wind the tape forward quickly (FAST FORWARD), RECORD, STOP and EJECT
• a tape counter
• a jack socket for an external microphone
• a recording-level volume control that allows you to adjust the volume at which you record
• a recording-level meter
• the option of using either mains or battery power
• a jack socket for headphones
• a built-in speaker.

Cassettes

• Use 60-minute cassettes for recording oral history. They are physically thicker than the longer-playing ones, so they are less likely to stretch (and thus distort the sound) or break. Buy 'normal' tapes, not metal or high-bias ones. The latter are designed for recording music and are too expensive for this purpose.
• Use cassettes with cases that screw together rather than those that are glued. Sometimes tape gets tangled, and if you can unscrew the case you may be able to fix the problem.
• Use only named brands of cassettes such as Sony and TDK.

Other equipment

• Batteries are expensive, so use an adaptor, which allows you to plug your tape recorder into the mains supply.
• If you have to use batteries for your recorder, you will need a battery tester to ensure they are fully charged. If they are not, when you are recording the tape will wind through the machine slowly. When you play the tape back at normal speed the voices will be distorted. Battery testers can be bought cheaply from electronics stores.
• For tape recorders you will need some cotton buds and isopropyl alcohol, readily and cheaply available from chemists, for cleaning the heads (i.e., the bit the tape runs over in order to record). This method is more efficient and cheaper than using commercial head-cleaning cassettes.
• A bag such as a camera bag is useful for carrying your equipment and protecting it from damage.

Microphones

• If you are buying microphones, go for the best quality you can afford.
• Always use an external microphone for recording oral history – not one built into the recorder. An inbuilt microphone will record all sounds indiscriminately, including the noise made by the recorder itself. It is difficult to position a tape recorder with an inbuilt microphone so that all voices are recorded clearly.
• The ideal for oral history recording is to use two lapel microphones that clip onto the clothing of the interviewer and the interviewee. Lapel microphones tend not to record as much background noise as free-standing ones because the body of the wearer helps to absorb unwanted noise. Their only disadvantage is that most recorders do not have an input for more than one microphone, so while the interviewee is recorded clearly, the interviewer sounds very distant. There are two solutions: buy a recorder with two microphone input jacks, or buy a 'split cord' that allows you to plug two microphones into one cord and then into the recorder.
• Electret condenser or dynamic microphones are particularly good. Talk to someone at your local electronics shop or contact a manufacturer to find out what model would be best for your requirements. Tell them you will be recording voices, not music.
• If you are buying only one microphone, you will need one with a stand, not one that has to be held. Hand-held microphones record any sound from the movement of the microphone itself. Free-standing, or table-top, microphones are generally quite unobtrusive and record both the interviewee and interviewer clearly if they are placed carefully. However, they often pick up an undesirable level of background noise.

Microphones pick up a range of noise in four patterns. The different types are:

• uni-directional or cardioid, which pick up sound in a heart-shaped pattern in one direction. They generally record sound around them but not directly behind them. These are the best type to use.
• omi-directional, which pick up sound coming from all directions
• bi-directional, which pick up sound from two opposite directions
• hyper-directional, which pick up sound from one direction only and have a very narrow field.

Familiarising yourself with your equipment

Before you start recording interviews practice as much as possible with a friend or family. Experiment with recording levels and with placing the microphone(s) at different distances from an interviewee. You are aiming to make recordings in which both the interviewee and the interviewer are clearly audible and unwanted background or tape noise is minimal.

To set up for an interview:

• Plug the recorder into the wall or put in the batteries. Switch it on.
• Put a battery in the microphone if it needs one, and plug it into the microphone jack socket. Turn the microphone on. (Yes, even professionals sometimes forget!) Always check the microphone battery before going to an interview, and carry spare batteries at all times.
• If using a tape recorder, make sure you have the tape in the right way, and remember that nothing will be recorded on the clear plastic lead-in at the beginning, so wait until it has wound through before you start talking. Alternatively, wind the lead-in tape through manually so that you can begin to record as soon as you press the RECORD button.
• Check that you have the recording volume adjusted to the correct level and your playback volume turned off. If you do not, you may experience a shrieking noise called feedback.
• Place the microphone on the table or clip it to the interviewee.
• Press the RECORD button or the RECORD and PLAY button, depending on your machine. Remember that if your recorder has only a playback volume control, this does not control the recording level, which you can adjust only by moving the microphone or speaking more loudly or softly. If you have only one clip-on microphone, place that on your interviewee and speak up yourself. While it is more important to record their voice than yours, it is useless if the listener to the tape is unable to hear your questions, so make sure that your voice is also audible. For a unidirectional, table-top microphone, the optimum position is for the two of you to speak over it at an angle of 90 degrees.
• Practice setting up your equipment quickly and efficiently.
• Take the time to experiment with different recording levels on your machine and with changing the distance of the microphone from the interviewee so that you know the optimum positions for recording.
• Make at least one practice interview, preferably with someone you know so that you are not afraid to make mistakes. This will give you practice in interview techniques and help you become confident in using your equipment.

Noise problems

Sometimes you will find that you have made a recording that has an unacceptable level of unwanted noise. Listed below are some common noise problems and suggestions for their solution.

Hiss

• This problem may be caused by recording at too low a level. Turn up your recording-level volume. Alternatively the heads may need cleaning or demagnetising. The latter can be done by a professional, or it is possible to buy special demagnetising tapes. Read the instructions carefully.

Hum

• The microphone may be too close to the machine and be picking up the mechanical noise of the recorder. Move it away. The machine and microphone may be too near a power source or on or near another electrical appliance. Move them.
• The wiring on your machine or microphone may be faulty. Have them serviced if you think this is the problem.

Whistle

• This can be caused by a television, radio-telephone or radio-paging system. The only way to stop it is to turn off the apparatus causing the problem.

Distortion

• If the level is set too high when recording digitally, this can cause clipping, which is unwanted distortion of the audio. While distortion happens in analogue recording as well, the artifacts caused by digital distortion can be more severe.
• A popping noise when people say 'p', a whistle when they 's' or a sizzling noise when they say 't' occurs because either they are speaking too close to the microphone or the recording volume is too high.
• Change the angle of the microphone, move it further away or turn down the recording level.
• If you are recording someone with a high-pitched voice, you may need to adjust the recording volume.

Echo

• This is the result of recording in a room that has few soft furnishings and no carpet, such as a kitchen. The sound bounces back off the hard surfaces, because there is little to absorb it, and is re-recorded.
• You may get around this problem by moving the microphone closer to the interviewee, placing it on a cushion to absorb the echo, drawing the curtains, or moving to another room. A lapel microphone is helpful because the interviewee's body will absorb a lot of echo.
• The effect will prevent broadcast-quality recording, but the quality will be acceptable for research purposes.

Microphone cable noise

• This is crackling or a clicking noise on the tape caused by the movement of the microphone cable, and it usually happens if you are holding the microphone.
• It is best to use a microphone stand while recording. Alternatively, place the microphone on some magazines or a cushion. If you have to hold the microphone while recording, wrap the cable around your hand.
• Cable noise sometimes occurs when you use a clip-on microphone and the interviewee fidgets with it. If this happens, explain politely that this will muffle their voice on the recording and ask them to stop. You may wish to give them something else to play with – a rubber band is an ideal toy for restless fingers, as it makes no noise.

Recording outside

• You should avoid interviewing outside, if possible, because it is almost impossible to control the recording of background noise.
• If you cannot avoid recording outside you will need some sort of windshield for the microphone, either a foam-rubber one that you can buy, or something like a handkerchief or a few layers of muslin secured with a rubber band.
• Try to place the recorder on the ground or a wall, as the motor speed may vary if it is hanging from your shoulder, and the sound will be distorted when you replay the tape.

Other sounds that you may inadvertently record are:

• rustling paper
• clicking pens
• fluorescent lights and clocks (both of which tick)
• traffic noise
• cage birds
• barking dogs
• open fires.

To avoid the first two, use a pencil and write your questions and notes on card rather than paper. There is little you can do about the others except to notice them at the preliminary meeting and suggest recording the interview in another room.

If you deliberately record some of the above effects when you are practising with your equipment, you will hear how irritating they sound when the tape is played back. You will then realise why you need to make clearly audible recording for oral history, particularly if you are collecting for an archive.

Check the equipment manual for care and cleaning instructions and follow them.