connect(ui->locut_cutoff_knob, &QDial::valueChanged, this, &MainWindow::cutoff_knob_changed);
connect(ui->limiter_threshold_knob, &QDial::valueChanged, this, &MainWindow::limiter_threshold_knob_changed);
connect(ui->compressor_threshold_knob, &QDial::valueChanged, this, &MainWindow::compressor_threshold_knob_changed);
connect(ui->locut_cutoff_knob, &QDial::valueChanged, this, &MainWindow::cutoff_knob_changed);
connect(ui->limiter_threshold_knob, &QDial::valueChanged, this, &MainWindow::limiter_threshold_knob_changed);
connect(ui->compressor_threshold_knob, &QDial::valueChanged, this, &MainWindow::compressor_threshold_knob_changed);