{"id":1765,"date":"2016-02-14T14:16:45","date_gmt":"2016-02-14T19:16:45","guid":{"rendered":"http:\/\/pugix.com\/synth\/?p=1765"},"modified":"2018-03-17T09:29:36","modified_gmt":"2018-03-17T14:29:36","slug":"ieaskul-f-mobenthey","status":"publish","type":"post","link":"https:\/\/pugix.com\/synth\/ieaskul-f-mobenthey\/","title":{"rendered":"Ieaskul F. Mobenthey"},"content":{"rendered":"

\"IFM-euro\"<\/a><\/p>\n

Pictured are six modules, in four flavors, from Peter Blasser.\u00a0 He designated his line of Eurorack modules as Ieaskul F. Mobenthey (IFM).\u00a0 I have four of the five IFM modules.<\/p>\n

Why the Blue Knobs?<\/h5>\n

IFM modules have knobs with all yellow pointers.\u00a0 It can be confusing as to which are the basis knobs and which are the attenuverters.\u00a0 Well, I happened to have lying about some knobs from Blacet modules that I had converted to 5U MOTM format.\u00a0 They fit the pots perfectly and are only slightly smaller in diameter than the ones that were replaced.\u00a0 Now all the pots with a bow-tie symbol are blue.<\/p>\n

Denum<\/h4>\n
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The Denum module is essentially a bounds\/bounce oscillator. It has the \u201ctriangle core\u201d circuitry used in many oscillators, but it adds a correlated bounds modulation.\u00a0 Here, bounds and bounce are each given equal treatment, with separate linear and exponential controls and inputs. In addition, this module has a fully featured bi-polar VCA with complimentary inputs, to get you quickly going sending \u201cbb-objets\u201d out the left and right channels.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/blockquote>\n

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Bounds Modulation<\/h5>\n

In the simplest terms, ‘bounds’ are the upper and lower voltage boundaries that the output reaches, before reversing direction.\u00a0 In most modular oscillators the bounds are fixed, typically at +5 and -5 volts.\u00a0 Modulating the frequency does not change the bounds; the amplitude remains constant.\u00a0 Bounds modulation means controlling the upper and lower bounds, and hence the amplitude of the output.\u00a0 But, changing the bounds also changes the frequency, since smaller bound take less time to reach.\u00a0 Thus bounds modulation is simultaneous frequency and amplitude modulation.<\/p>\n

Denum is a wide-range VCO, with three switch-selected ranges going from very slow LFO to virtually ultrasonic.\u00a0 Without any bounds modulation, the output swings 5 volts peak-to-peak around zero.\u00a0 The pulse output is a huge +\/-10 volts.\u00a0 Patching the triangle output back into its own Bounce CV input results in different, but still symmetrical waveforms.<\/p>\n

The VCA in Denum<\/h5>\n

The VCA is unusual in a number of ways.\u00a0 There are two outputs, left and right, each having its own input, with both inputs normally connected to the triangle output of the oscillator.\u00a0 There are two CV inputs, but they behave in an interesting way.<\/p>\n

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If the left (CV) input is greater than right, sound goes out the \u201cleft out\u201d. If right is greater than left, sound goes out the \u201cright out\u201d. The voltage amount of difference maps to loudness in these channels.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/blockquote>\n

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You can patch into the VCA left and right inputs, disconnecting them from the Denum oscillator. My notes made while checking out the VCA:<\/p>\n