On Tue, Aug 26, 2014 at 03:46:59PM +0200, Ralf Mardorf wrote: > > "2.23 DC Offset Remover (dcRemove, 1207) > > > > Simply removes the DC (0 Hz) component from an audio signal, uses a high > > pass filter, so has some side effects, but they should be minimal." - > > http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html#tth_sEc2.23 > > > > Would this protect against phasex loudspeaker-heater feature? > > It's said it's not audible, IIRC I sometimes heard a loud, very loud > single crackle. Could this be caused by a dc offset? Yes. The problem here is that the DC offset originates in the oscillators and is multiplied by the envelope. Hence the result is not really constant. A highpass filter will remove the constant or slowly changing part during a note, but not the 'thumps' at the beginning and end. Depending on the cutoff frequency and the rise and fall times of the envelope these could still be much larger than the signal. They won't probably fry you speaker but could result in clipping and hence crackles. The only real solution is to remove the DC offset at the output of the oscillators, before it enters the rest of the audio chain. -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow) _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
