{"id":5232,"date":"2022-12-13T17:56:43","date_gmt":"2022-12-13T22:56:43","guid":{"rendered":"https:\/\/pugix.com\/synth\/?p=5232"},"modified":"2022-12-13T17:56:45","modified_gmt":"2022-12-13T22:56:45","slug":"inertia-vco-modulations","status":"publish","type":"post","link":"https:\/\/pugix.com\/synth\/inertia-vco-modulations\/","title":{"rendered":"Inertia VCO Modulations"},"content":{"rendered":"\n
\"\"<\/figure>\n\n\n\n

This post covers New Systems Instruments Inertia<\/strong> in High<\/strong> range, i.e. for use as an oscillator or filter. For audio oscillation, mode is usually set to Skew<\/strong>, which allows frequency and waveshape to be controlled separately. But I’ll show one example of using Rise\/Fall<\/strong> mode for the VCO that let’s you modulate only the rise time while keeping the fall time at a constant, fast setting. (This technique is often used with slope generators operating as oscillators.)<\/p>\n\n\n\n

In High<\/strong> range mode and Skew<\/strong> mode, set all pots to 12 o’clock except for Momentum. Turn Momentum<\/strong> fully clockwise to achieve self oscillation. The V\/O input and the CV Frequency input can both be used for Frequency Modulation (FM). Without any external FM CV, centering the Frequency knob lands you around 500 Hz. I measured Order 1 out swinging -7.0V to +6.0V and Order 2 Out at -5.4V to +5V, lagging 45 degrees behind O-1. Both are approximating a good sine wave. Rotating Frequency fully CCW to full CW gives a sweep range from ~1Hz to ~25Khz<\/strong>. Leaving Frequency centered, a +5V into the Freq CV input, will sweep the same range using the attenuverter pot.<\/p>\n\n\n\n

Standard Frequency Modulation<\/h2>\n\n\n\n
\"\"
Yellow is Order 1 output. Blue is modulating signal to Freq CV input.<\/figcaption><\/figure>\n\n\n\n