Audacity Forum

I am producing a relaxation/visualization audio, and many of the s's have a slight distortion and in some cases a whistle.

I have tried all of the effects including low pass filter, and have had no success.

Here's a link to a sample clip: http://defoore.com/NICIntro.mp3

If you listen to the clip, you'll hear several places where there is a "whistle" in the s sounds.

How do I eliminate the whistle and generally take the harshness off the s sounds?

Thanks in advance for your help!

William

I've tried all effects, without success--the "s's" in the speaker's words have a hiss and an occasional whistle.

I posted about this earlier, and got no reply, so I thought I'd try again with a different subject line.

Suggestions?

wgdefoore wrote: I posted about this earlier, and got no reply, so I thought I'd try again with a different subject line.

Probably because no-one really knew what you meant.

wgdefoore wrote:the "s's" in the speaker's words have a hiss and an occasional whistle.

The description sounds like you mean that there is an over emphasis of sibilance.

How have you recorded it? (in detail - what sort of microphone, microphone position ... if you want someone to have exactly the same set up, what do they need and what do they need to do?)

How are you listening to it?

Could you post a short sample (just a couple of seconds) exported directly from the original Audacity recording as a WAV file (not MP3).
Small WAV attachments can be uploaded directly to the forum (see "Upload" tab below the "Compose Message" window).

Hi Steve

Thanks for your response. Yes, it does sound like a sibilance issue.

I've attached the short WAV sample.

I use a Shure wireless mic, UT4A receiver, UT1-VQ mic. I clipped the mic onto my shirt, a little below my chin, about shoulder level. I record through a Mobile Pre amp, into my computer.

I've listened over my computer speakers, through a sound system, and with headphones, same results.

I think that's everything you asked for.

William

Yes, there's a bit of a sibilance issue, but I've heard much worse
Unfortunately it is a tricky problem to deal with.
The generally accepted tool for dealing with sibilance is a de-esser, but 1) they don't usually work particularly well unless the sibilance is unusually well defined in terms of frequency range, and 2) I'm not aware of a good de-esser that works with Audacity (I started working on a Nyquist De-esser plug-in a long time ago, but it's a tough nut to crack. I produced a prototype that worked reasonably well compared with other de-essers, but it was quite tricky to use - I'll have to look into that again at some time). I would not expect a de-esser to work particularly well on this audio sample.

Other than than de-essers, the other tool for treating what you've already recorded is the Graphic Equalizer. There's a lot of spikes in the spectrum at around 4400 Hz that could do with coming down a bit, but attacking the sss's to hard with the Equalizer will make the whole recording sound dull. Better to just take the edge off a bit at around 4400 Hz, and fill in the low-mid frequencies by boosting them a bit.

My main recommendation would be to try a different microphone and/or different microphone positions.
Tie-clip microphones will often produce overly bright recordings. This is often a desirable design goal as it can improve intelligibility, particularly on tape based recorders and through poor quality "announcement" PA systems. Tie clip microphones are not really ideal for recording other than in very specific situations where other types of microphone are not practical alternatives. Having said that, the position of the microphone can make an enormous difference - for example, have you tried clipping it high on a jacket collar rather than under your chin?

Thanks, Steve--that gives me plenty to work with.

I appreciate your help,

William

Move the microphone further from your mouth, angling it to one side or lowering the mic and angling it more towards the ceiling. See:
http://www.eqmag.com/article/vocal-cord ... n-08/33059

If you select one of the sibilants and Analyze > Plot Spectrum you will see a large broad spike centred on 4500 Hz which you want to attenuate, though frankly the only way to fully cure it is re-record it.

You can attenuate frequencies using Effect > Equalization. If you chop down the 4000 Hz - 5000 Hz frequencies the result will be duller and quieter, but you can then try Effect > Compressor to reduce dynamic contrast (and that will also normalize to maximum volume for you by default).

If you want to try a plug-in there is the Nyquist notch filter (just enter the values you want in text boxes) or try the VST Spitfish de-esser.

To install new plug-ins, place them in the Plug-Ins folder inside the Audacity installation folder and restart Audacity. On Windows computers the installation folder is usually under "Program Files". For VST plug-ins (unless this is your first VST plug-in), you also need to click Edit > Preferences: Effects and check "Rescan VST effects" before restarting.



Gale