2. Choice and maintenance of equipment
In all areas of making original recordings and producing archival copies, the use of equipment of a professional or, at the very least, semi-professional standard is vital. By professional equipment we mean the sort which comes up to modern standards of technology, which will guarantee a minimum of distortion and which will be sturdy enough to continue producing recordings of the highest standard after hundreds and even thousands of hours of operation. By semi-professional equipment we mean the sort designed for the discerning amateur which, in its technical performance, will almost if not totally equal that provided by professional equipment. Of course, semi-professional equipment is not as sturdy in its construction as the professional variety and its performance will decline after extensive use.
Above all, these basic principles apply to the tape recorder which is the vital organ of the technical system in all modern research programmes. If it is at all possible financially, both stationary and portable equipment should be of the professional kind. In view of the small number of companies which deal in equipment of this class, and of the comparable price-to-performance ratio of different products, the choice of a specific make is not critical. From the point of view of efficiency, however, it is best to choose a manufacturer with outlets across the country or throughout the region as this will make servicing and the supply of spare parts that much easier. This generally means using the makes and types of equipment used in local or national radio stations. This approach is particularly recommended for countries outside Europe, if one is to avoid the risk of recording sessions being held up for several weeks when equipment breaks down. Of course, semi-professional equipment can also be used for recording but any savings on purchase costs must in the long run be offset against higher outlays on servicing and repairs. However, these cheaper types of equipment may be used in cases where less precise copies of high quality recordings suffice, such as in monitoring. 1
Of all audio equipment, the tape recorder requires the most thorough maintenance. This is because each individual machine has to be very carefully tuned to match the tapes compatible with it, if the optimum performance is to be obtained from both together. With continuing use the tape heads are gradually worn down, impairing the performance, and regular adjustment is absolutely vital if the best possible quality is to be retained. Moreover, electrical parts can, without any warning, become defective regardless of how long they have been in use and it is essential that tape recorders and the adjustments made for the tapes used on them should be continually monitored. In general, the following service schedule might be used as a reasonable guideline for professional equipment:
Daily (or every time a machine is used): check the frequency response and carry out an auditory test.
Weekly: clean and demagnetise the tape heads and tape paths.
Two monthly (or after every 50 hours use): carry out a full service.
In the case of semi-professional equipment (especially with machines which receive rather rough handling or are used to record a unique or rare occasion) it is advisable to carry out the above procedures at more frequent intervals. A full service on a professional piece of equipment will take between one and two hours (as long as no serious repairs are necessary) but about twice as long is to be spent servicing a semi-professional set. If it is at all possible financially, institutions should employ their own well qualified audio service technician for this work. Even if an institution has only a small amount of equipment such a technician, qualified in the right field, can be given the job of producing copies and looking after the collection. In this way institutions will avoid the need to rely on the often shoddy workmanship of servicing firms and at the same time find it easier either to carry out or to supervise the extensive servicing of equipment necessary in order to maintain archival standards. A written record should also be kept of this work. Managing all this, of course, requires a whole series of test apparatus and tools and, last but not least, a workshop.2 Lack of the necessary financial resources or shortage of skilled technicians may make this impossible, in which case one should always try to work in close co-operation with similar institutions which share the same service requirements and with whom a solution to one's needs might more easily be achieved. Alternatively, one might enlist the help of local or national radio stations.
Microphones should be chosen with great care. Not only do they have to satisfy specific technical requirements, they should also be tested in a properly equipped workshop whenever they have been extensively used (once a year at least and whenever they have been dropped or similarly mistreated). Here again, if the necessary facilities are not otherwise available, institutions of a similar nature should work together or, where there are no other similar institutions, radio organizations should be consulted for technical expertise and advice.
- Price ranges for tape recorders (¼ inch tape, mono or stereo, prices and exchange rate as of June 1982) are as follows. All prices quoted are in US dollars, ex-works, excluding import duty and taxes.
Stationary professional sets .............$ 3,500 to 8,000
Stationary semi-professionals sets ...$ 1,000 to 2,000
Portable professional sets ............... $ 4,000 to 6,000
Portable semi-professional sets.......... $ 600 to 1,000
- For the range of essential measuring devices and equipment one should be prepared to pay at least US $3,000.
