[linux-audio-user] Removing AC hum after the fact.

[Adam Sampson]

"Alex Polite" <notmyprivateemail at gmail.com> writes:

> Are there any tools that will help me define the notch filter by
> looking at the my audio?

Jamin's actually quite good for doing this, since it's got a nice
spectrum display and interactive EQ settings. Failing that, you could
use a LADSPA filter (like "Single band parametric") and a spectrum
analyser (like Jaaa) and just tweak the filter settings until the peak
you see on the analyser disappears.

[player] -> [JACK Rack with SBP] -----+----> [recorder]
                                      |
                                      v
                                    [Jaaa]

If it's really mains hum, then you can probably just cut the
frequencies below 130Hz or so.

-- 
Adam Sampson <ats at offog.org>                         <http://offog.org/>