Okay so, first of all, you need the sound cut use mp3cut, then all you have to do is to go to Online Audio Converter and convert your version being .mp3 or .wav.
Another similar website is Audio online-convert, which also has the option to normalize the sound and is a good idea to use it.

Anggara_nothing wrote: now, the true mp3's format : (for CS 1.6)
Joint Stereo
44100 Hz
128 kbit

then convert it download it and sent it on discord in suggestion channel or here in this topic.
This is how the setting for .wav should look like:
Anggara_nothing wrote: the true wav's format : (for CS 1.6)
Microsoft PCM
Mono (1 channel)
22050 Hz
16 bit (8 bit also works just fine)

then convert it download it and sent it on discord in the suggestions channel or here on this topic.
Use Aaudiomass if you need more editing of the sound.
Wav Compressor
You are done and remember in the end it's up to me if I am gonna add it or not, plus we can't have an unlimited amount of sounds after all.

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