The Oakland Symphony Chorus uses a digital recorder to record our weekly rehearsals, and I process the .WAV files into MP3s in Audacity. I just upgraded to Audacity 2.0.6, on my Win7 Pro 64 bit laptop. My problem isn’t with Audacity, it seems to be performing fine.
About 12.5 minutes into the second half of last night’s rehearsal, the building fire alarm - or maybe the burglar alarm - went off. We were rehearsing the Mozart Requiem, which we perform in about 3 weeks, so we just kept singing (it was clear the building WASN’T on fire, and nobody could see a burglar). It took about 4 movements for our support team to figure out how to turn the thing off. We have a Zoom H4 recorder with directional condenser mics, but the alarm was behind the chorus, so the H4 picked the sound up.
I’m looking at the .WAV files in Audacity and I can hear the alarm when it comes on, but I can’t see anything I can pick out of the signal to edit the alarm noise out of the recording. Is it possible to get rid of this? What would I do?? There are a couple of stretches on the audio where the alarm is all you can hear, can I use that to identify the signal for removing it? Help. I’d hate to publish the podcast with the alarm but I may have to.
Anything you do will be unsatisfactory. You won’t be able to remove the alarm sound without also destroying the music.
Noise reduction works best when you have a constant low-level background noise. Or if it’s a single pure-tone (like power line hum) that can often be notched-out. Something like a siren or dog barking can’t be removed.
Even with the latest high-end software, pros still record in soundproof studios (or reasonably-well sound-insulated halls). And, on-location movie dialog is re-recorded in the studio, etc.
I’d hate to publish the podcast with the alarm but I may have to.
If it was my decision, I probably wouldn’t publish it. It’s going to create an amateurish image of everyone involved. You said it was a rehearsal. Maybe you can delay the podcast until after you record the actual performance.
Doug, thanks for your quick reply. I was afraid that was the case, it’s good to know.
In fact, I do plan to publish it. This is not a podcast to show how well we sound (thank God). It is on Blogger but explicitly is not indexed; we tell people where to find it. It’s a working podcast that the singers use to practice. This means that what we sound like, the tempos, and especially the director’s comments on technique and interpretation, are still useful working tools, even with that awful noise in the background.
If you know the Mozart Requiem, you’ll be amused (we were) that it started when we began the Confutatis Maledictis (if you don’t know it, the general meaning is, you’re going to hell…)
The pros who record in (reasonably) sound-proof studios have more money than a local nonprofit…
The pros who record in (reasonably) sound-proof studios have more money than a local nonprofit…
Of course. The point I was trying to make is that even with better software, you can’t fix this… Pros still go to great lengths and great expense to prevent noise because it’s so difficult (or impossible) to remove.
And with careful positioning of the recorder/mics (after some experimentation), I’d expect that you can get some very good recordings with the Zoom!
Anything you do will be unsatisfactory. You won’t be able to remove the alarm sound without also destroying the music.