BS 6840-13:1998

Clause
1 General
    1.1 Scope
    1.2 Reference documents
    1.3 Explanation of terms
2 Listening conditions
    2.1 Listening room
          2.1.1 Room dimensions
          2.1.2 Reverberation time
          2.1.3 Environmental conditions
    2.2 Loudspeaker position and orientation
          2.2.1 Monophonic reproduction
          2.2.2 Two-channel stereophonic reproduction
          2.2.3 Multi-channel stereophonic reproduction
    2.3 Listening position
    2.4 Level setting
          2.4.1 Listening level
          2.4.2 Relative level
    2.5 Electrical requirements
          2.5.1 Signal source and amplifiers
          2.5.2 Switching system
          2.5.3 Connections
          2.5.4 Overall frequency response
3 Listeners
4 Programme material
5 Experimental procedure and evaluation
    5.1 Experimental procedure
          5.1.1 Single stimulus ratings procedure
          5.1.2 Paired ratings and paired comparisons
                  procedures
   5.2 Rating scales and perceptual attributes
          5.2.1 Rating scales
          5.2.2 Perceptual attributes and their
                  definitions for this report
   5.3 Test duration
   5.4 Instructions and preliminary trials
   5.5 Statistical treatment of the data
6 Test Report
Annexes
A Instructions for listening tests
B Statistical treatment of the data from listening tests

Setting-up, performance and evaluation of listening tests on loudspeakers intended for household systems and environments. Although designed to cover separate sound system components these procedures with minor changes could apply to radio receivers and television sets etc.

The recommendations in this report apply to loudspeakers intended for residential systems and environments. Although the procedures are specifically designed for loudspeakers which are separate sound system components for either monophonic, two-channel stereophonic or multichannel stereophonic reproduction, they may also be applied to other devices such as complete audio and television receivers with integrated sound.

This report gives recommendations for establishing, conducting and evaluating listening tests on loudspeakers. Although various aspects are under continuing discussion, this report is intended to give the general guidelines.

Certain aspects may vary — in particular, the listening room may reflect regional construction practices. The tests described in this report are to be performed in a room the size and acoustical properties of which are similar to those of an “average?? living room. Specific recommendations about the room size, acoustical properties, arrangements of loudspeakers and listeners, and environmental conditions are given.

This Technical Report describes experimental procedures, including recommendations on the choice of programme material and the processing and presentation of the final data. It may be useful, when applying the methods of this publication, to also consider some of the recommendations in AES 20, especially as concerns the range of perceptual attributes as listed in 5.2.2.

It should be understood that the topics of experimental design, experimental execution, and statistical analysis are complex, and that only the most general guidelines can be given. It is recommended that professionals with expertise in experimental design and statistics should be consulted or brought in early in the planning of the listening test.

The use of multi-channel formats, principally for domestic presentation of cinema, is becoming more widespread. The procedures described in this report are applicable to any number of channels of reproduction. Because of the rapidity with which the practices in this area are evolving, only the most general guidelines are given.