//cpp
void __fastcall TForm1::Button1Click(TObject *Sender)
{

HINSTANCE bass=LoadLibrary("BASS.DLL"); // load BASS
//BASS_Init=GetProcAddress(bass,"BASS_Init"); // get BASS_Init
*((void**)&BASS_Init)=GetProcAddress(bass,"BASS_Init");
//BASS_Init(-1,44100,0,hWnd,NULL); // call BASS_Init

}
//---------------------------------------------------------------------------

//h
#define BASSDEF(f) (WINAPI *f) // define the functions as pointers
//---------------------------------------------------------------------------
class TForm1 : public TForm
{
__published:	// IDE-managed Components
    TButton *Button1;
    void __fastcall Button1Click(TObject *Sender);
private:	// User declarations
public:		// User declarations
    __fastcall TForm1(TComponent* Owner);

    BOOL BASSDEF(BASS_Init)(int device, DWORD freq, DWORD flags, HWND win, const GUID *dsguid);
};
//---------------------------------------------------------------------------
extern PACKAGE TForm1 *Form1;
//---------------------------------------------------------------------------
#endif

BOOL (WINAPI *BASS_Init)(int device, DWORD freq, DWORD flags, HWND win, const GUID *dsguid);

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
extern "C" {
#include "bibl.h"  // шло вместе с библиотекой
}