> The above table is a consolidation of ISO 3, ISO 17, and ISO 497 of 1973, > which were copied from the pre-war DIN 323. The series that I have > denoted > as R'3 is very common although it does not appear in these documents..
Thanks for posting that. I used the R10 during sound and vibration work and called the series 'one third octave' but I see that there is a lot more to it than that. The series is attributed to the French Colonel Charles Reynard in 1877. I thoroughly recommend you read this webpage: http://www.sizes.com/numbers/preferred_numbers.htm -- Terry Simpson Human Factors Consultant [EMAIL PROTECTED] www.connected-systems.com Phone: +44 7850 511794
