I'm looking for library having such functions or procedures:
to stick several *.wav,
to  do loud *.wav,  to change speed, tone, or something similar.

I want to used  searched library in Visual Basic.
The searched library must be free for individual user.

To stick several *.wav by  using play in VB isn't interested for me,
but if there isn't another way, I accept it.

Or, I looking for way of changing the voice (or install new voice)
in Microsoft library system.speech,
but only with possibility to use normal polish way of speaking.

This newsgroup is for VB Classic only, VB6 or lower. For VB.Net, try this
group:

news://microsoft.public.dotnet.languages.vb

I tryed, but without effect.

VB6 and VB.Net are not compatible. If you find a VB6 solution, you have to
rewrite it to make it work with VB.Net. See this article:

http://en.wikipedia.org/wiki/Visual_Basic_.NET#Criticism

I suggest that you search google groups, or reply to your own post on the
dotnet newsgroup and ask if anyone has any suggestions.

On the other hand, if you are just trying to combine wav files, try this
fully featured sound editor:

http://en.wikipedia.org/wiki/Audacity

It's free and open source.

Please check the dotnet group, I just posted a response.

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