Blue Velvet Soft Clip Mixer

The Blue Velvet Mixer from Dome Music Technologies is a soft-clipping audio mixer which can add subtle warmth or create more extreme saturation and distortion effects. It employs the R_OpenLib oversampling library (developed by Chris Neuberger of R_Ware) to prevent generated overtones from aliasing.

Input channels 1 to 3 are added together and fed into the ‘Drive’ gain stage.

The Direct input channel is multiplied by the bipolar level control and added to the Drive stage output.

The Bias control adds a DC offset to the audio signal. This causes asymmetrical distortion, and the generation of even harmonics.

The combined signals are then passed to the up-sampling process. This will project the signal into a virtual sample rate at multiples (1x to 16x) of the standard Voltage Modular 48kHz.

After up-sampling, the soft-clip transfer function is applied to the combined input signal.

Once the soft-clipping has been applied, the signal is then down-sampled and anti-aliasing filtered.

The output coupling mode switch has two settings – “DC” (default) and “AC”. In the DC mode, all DC offset voltages are preserved. This becomes especially evident when using non-zero values of Bias. In the AC mode, DC offset voltages are removed. This is achieved by applying a 6dB/oct high-pass filter to the output signal. The cut-off frequency of the filter is roughly 20Hz.

A comprehensive user guide is available on the Dome Music Technologies website.