SAUL MINEROFF ELECTRONICS NATURE DIVISION

• Special techniques have to be employed to record wild animals. Apart from unwanted noises such as vehicles, aircraft or wind which can spoil any outdoor recording, the main difficulty is that most wildlife cannot be approached closely. An ordinary microphone will not pick up a strong enough signal unless it is close to the subject. Halving the distance between microphone and the subject boosts the signal level by a factor of four. Therefore, placing a microphone close-up is the best technique to record animals; for example, a microphone can be left at the end of a long lead on a bird's regular songpost. But this can only be done if the habits of an individual animal are known, so the majority of field recordists record animals vocalizing at a distance using ultra-directional microphones or parabolic reflectors.
  
  
• A parabolic reflector (parabola) concentrates distant sounds onto a conventional microphone placed at its focus. The larger the diameter of the dish, the more amplification, but a practical size is around 18" (e.g., the SME PR-1000)
  
  
• Suitable microphones to use in conjunction with parabolas are dynamic microphones with a cardioid (directional) response. These are rugged, do not require a power supply and can be used without a parabola for other recording applications.
  
  
• Ultra-directional (super-cardioid) microphones or gun microphones are expensive and generally less directional and powerful than parabolas but are less cumbersome and have a flatter frequency response. They are popular with expedition recordists because of their compact size compared to parabolas. Most gun microphones are condenser type, requiring a power supply. The longest microphones are most directional and are used by bird and mammal recordists. Short gun microphones are ideal for recording animals such as amphibians and insects which can be approached closely. All types should be used with a pistol grip and shock mount unit as they are very susceptible to handling noise.
  
  
• Windshields. microphones are designed for indoor use, so windshields are essential for field recording in many locations, such as open grasslands, coasts, moorlands and hills, but they are not necessary in windless habitats (e.g., forests).

Recorders

• Solid state (flash card/disk drive) recorders have been developed in the last few years. These recorders use compact flash memory cards or computer drives to record. Some models offer a choice of recording in different file formats: the uncompressed format (e.g., PCM WAV file) should be used in preference to compressed (e.g., MP3) formats. As the memory is used up, the sounds are best downloaded to a PC or CD to free up space for more recording. These types of recorders are an attractive alternative to other types of recorders.
  
  

Other Equipment

• Connecting leads and plugs between microphones and recorders must be strong to withstand heavy use. They should be of the right length so that the microphone or parabola can be held away from the recorder (to avoid machine noise), but not so long that loose wire snags on vegetation or causes extraneous noise when in use. Most professional microphones can be supplied with the correct lead and plug to fit the microphone input of your recorder. Gas soldering irons are very compact and ideal for repairs in remote locations.
  
  
• Headphones are not essential but help in monitoring the level of recorded signal, checking against distortion and also help to aim directional microphones/parabolas while recording.
  
  
• Tripods or monopods that can attach to the carrying handles of parabolas or gun microphones are very useful if one can manage to carry this extra item of baggage. They eliminate handling noise and leave hands free for controlling the recorder, binoculars, etc.