Ich habe eine Beep-Klasse geschrieben.
Sie beherrscht einzelne Töne, Sinuston und einen Tonverlauf (Tonleiter)

Hier isset:

Beep.h

//---------------------------------------------------------------------------

#ifndef BeepH
#define BeepH
//---------------------------------------------------------------------------
#include <windows.h>
#include <math.h>
//---------------------------------------------------------------------------
class TBeep
{
private:	// User declarations
protected:      // User declarations
public:		// User declarations
        __fastcall TBeep();
        void __fastcall Tone(int freq,int ms);
        void __fastcall Wait(int ms);
        void __fastcall Sine(int freq,int ms,int steps);
        void __fastcall Alarm(void);
        void __fastcall Siren(void);
        void __fastcall Gradient(int freq1,int freq2,int steps,int ms);
};
//---------------------------------------------------------------------------
#endif

Beep.cpp

//---------------------------------------------------------------------------

#include <windows.h>
#include <math.h>
#pragma hdrstop

#include "Beep.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
//---------------------------------------------------------------------------
__fastcall TBeep::TBeep()
{
}
//---------------------------------------------------------------------------
void __fastcall TBeep::Tone(int freq,int ms)
{
        Beep(freq,ms);
}
//---------------------------------------------------------------------------
void __fastcall TBeep::Wait(int ms)
{
        Sleep(ms);
}
//---------------------------------------------------------------------------
//-- Einfacher Sinuston, dh, er geht immer auf und ab.
//-- z.B.
//--Sine(440,10000,100)
//---------------------------------------------------------------------------
void __fastcall TBeep::Sine(int freq,int ms,int steps)
{
        int spect = 120;
        double x;
        int i = 0;
        while (i < steps)
        {
                x = (double)i/(double)steps*(double)360;
                Tone(freq+sin((double)x*(double)3.141/(double)180)*spect,ms/steps);
                i++;
        }
}
//---------------------------------------------------------------------------
//-- Einfacher Alarm (Wecker
//---------------------------------------------------------------------------
void __fastcall TBeep::Alarm(void)
{
        int ms = 1000;
        int freq = 880;
        int i = 0;
        while (i < 3)
        {
                Tone(freq,150);
                Wait(100);
                i++;
        }
        Sleep(250);
}
//---------------------------------------------------------------------------
//-- Siraene
//---------------------------------------------------------------------------
void __fastcall TBeep::Siren(void)
{
        int ms = 1000;
        int i = 0;
        Tone(391,ms/2-ms/20); // G
        Wait(ms/20);
        Tone(293,ms/2-ms/20); // D
        Wait(ms/20);
}
//---------------------------------------------------------------------------
//-- Tonverlauf
//-- z.B.
//-- Gradient(200,400,100,10000)
//---------------------------------------------------------------------------
void __fastcall TBeep::Gradient(int freq1,int freq2,int steps,int ms)
{
        int diff = freq2-freq1;
        int f = freq1;
        int i = 0;
        while (i < (steps-1))
        {
                Tone(f+i*diff/(steps-1),ms/steps);
                i++;
        }
        Tone(freq2,ms/steps);
}
//---------------------------------------------------------------------------

Wie gefälldet euch? CHECK IT OUT!!!

Dann einfach:
TBeep *beep;

beep = new TBeep();

beep->Alarm();

aber wie kann ich den Ton über die Boxen ausgeben lassen?
gibt es da nicht spezielle midi-dlls?