Granby
Yes half meter 45deg static test at 75% rpm

Moley
88db is very low, ambient noise in an underground station ticket office is between 75 and 80db, sad i know but we install PA/VA systems on LUL.
We have recently been installing the classical music background music you may of heard on the Northern line, This has to be set at 5db above ambient which is around 80db, dependant on size of station and its acoustic construction, just trying to give people an idea of what 80db is in reality,which is in a nutshell not very loud at all

The meter i have is not all singing and dancing,and does not need to be, the important thing is its calibrated to a 94db sound generator.

Would be interesting to test yours for sure.

http://www.javelintrackdays.co.uk/tr...id=5&Itemid=22

P.S

Will only be there for about an hour max guys