[LAD] Looking for the cause of pulsating noises

Ralf Mardorf ralf.mardorf at alice-dsl.net
Sat Jun 12 20:59:18 UTC 2010


I couldn't notice (in Germany we call it) 'pumping'. I don't think it's 
caused by auto-leveling. OTOH the pulsing noise might be caused by a 
strange limiter because of some peaks, but try to reproduce such a sound 
using LADSPA limiters, compressors on your computer. Ok, it might be 
caused on the analog domain, anyway, for analog limiters and compressors 
it's the same.

Regarding to a 'half level' recording. If the user hasn't got the 
equipment to reduce the level, a pocket handkerchief might help 
(unfortunately it would be a pass filter too ;).

Because it's a telephone, it might be all kind of strange noise. I guess 
we all know the sound a cellphone could cause to radios etc.. How do 
they prevent that such noise has no impact to the cellphone's audio itself?




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