View Full Version : Help remove background rumble from audio?

2009-10-09, 05:02 AM
Hi folks,
I recorded a show recently and noticed that halfway through, the recording has acquired a background 'rumbling' noise, which I think is caused by air movement from the air con (my fault for not using 'screens). It's not overpowering but is noticeable during quiet parts, it was an indoor venue so the rumble sound is fairly constant throughout. I just wondered if it's possible to remove/reduce the rumbling sound with some kind of post process filter? Any help would be much appreciated, I've attached a sample mp3 but can upload in wav format if anyone thinks anything can be done to improve it, thanks :hmm:

2009-10-09, 07:07 AM
you can use a low-cut filter [aka high pass filter], which basically lowers dB or cuts anyting below a certain frequency...you'll have to play around with it, but most "rumbles" occurs somewhere below 100Hz

start at 100Hz and then move lower in incremental steps until the rumble begins to appear again, then back it up a few Hz...you want to find the spot where yer rumble is not noticeable, but as much of the low-end is still there

2009-10-10, 02:17 AM
Ok, thanks for the suggestion AAR.oner, I'll give it a go :thumbsup

2009-10-10, 02:56 AM
BTW, remembering some of my older tapes I was trading over the years, that background rumble is called Motörhead. :thumbsup

2009-10-15, 10:31 AM
snap to zero crossings, & if you're not 100% impressed just leave it alone... sometimes these fixes can be tricky business, esp if you're inexperienced fwiw

2009-10-21, 08:11 AM
Cheers for the advice, still playing around with this but not making much headway, audio editing is really not my thing :hmm: Will keep trying though, thanks for the help:thumbsup

2009-10-27, 05:26 PM
Not too disturbing to be honest. Heard worse (mobile telephone, wind machines) - I would probably leave it. Part of the atmosphere...