private void BtnReset_Click(object sender, RoutedEventArgs e)
        {
            //markOnLeft = false;
            //isSimplified = false;

            OctOffset    = 0;
            HalfOffset   = 0;
            MarkOnLeft   = true;
            IsSimplified = false;

            tuneCVT = new TuneConvertHelper.TuneConverter(MarkOnLeft, IsSimplified);

            //CbSrcTune.Items.Clear();
            //CbDstTune.Items.Clear();
            CbSrcTune.ItemsSource   = tuneCVT.majorTuneList;
            CbDstTune.ItemsSource   = tuneCVT.majorTuneList;
            CbSrcTune.SelectedIndex = 5;
            CbDstTune.SelectedIndex = 5;
        }