The following demonstrates using a delay function that can be used to beep the PC speaker. Example:

procedure Delay(ms : longint);
{$IFNDEF WIN32}
var
  TheTime : LongInt;
{$ENDIF}
begin
{$IFDEF WIN32}
  Sleep(ms);
{$ELSE}
  TheTime := GetTickCount + ms;
  while GetTickCount < TheTime do
    Application.ProcessMessages;
{$ENDIF}
end;
procedure TForm .Button Click(Sender: TObject);
begin
  MessageBeep(word(- ));
  Delay(200);
  MessageBeep(word(- ));
  Delay(200);
  MessageBeep(word(- ));
end;