You have just recorded vocals, you did not forget the anti-pop filter BUT
some harsh sounds still remain. sss
How to get rid of those annoying sibilances, harsh sound on “s” “ss” “sh” “ch” “z” ?

=> You can edit by hand if you have time, but it can be very tedioussss !

• Spitfish - Free VST De-esser. SPITFISH serves as an easy-to-use de-esser. If you ever had problems with loud sibilants and s-like vocals, this device can help to make those nasty sounds much smoother. You can also apply it to other signals that might need some evening out within the upper frequency range, e.g. Cymbals and crashes.
• Spitfish is a free de esser VST, Audio Unit plugin developed by digitalfishphones. Compatible OS(s): Windows 64b, macOS. Spitfish is a dead-easy to use de-esser, aimed mainly at mono or stereo vocal tracks.Just like classic analog de-essers, this unit dynamically filters out harsh, annoying s-like sounds that would otherwise ‘spit’ in your face.

Or you can use a DE-ESSER, for automatically remove those annoying “s” in your vocal.
We have selected 3 FREE VST plugins you can use in Wavosaur or any audio editor or sequencer, that does the job ! let’s go :

Home › Free VST Plugins › 10 Free Guitar VST Plugins – Best Guitar VSTs 10 Free Guitar VST Plugins – Best Guitar VSTs Here are the best Free Guitar VST Plugins online that can be used with FL Studio, Reason, Ableton Live, and other VST supported software.

1. Spitfish

download for free ! => http://www.digitalfishphones.com/main.php?item=2&subItem=5

The gool old VST by DigitalFishPhones, it’s dead simple, and nothing prevents you from using two Spitfish in serie. It removes efficiently the “sss” sound.

Download Free Plugins Fl Studio

2. Lisp

Sleepy Time List VST

Information and download : http://sleepytimedsp.com/software/lisp/

This one comes with VST2 and VST3 version, as well as a 64 bit version!
Like spitfish, it has a stereo mode, and you can adjust the frequency for detecting the sibilant parts.
There are not so much freeware de-esser, this one is nice!

3. Tonmann de-esser

Direct download => http://www.tonmann.com/temp/Tonmann_DeEsser11.rar

Download Vst Plugins Free

This one has been made with synthedit surely. We didn’t give so much test but it seems to do the job! It has a clean and simple interface.