Will Marbles ever get fixed?

I found a long time ago the Audible Instruments Random Sampler has the outputs set to 0-10vdc but the Mutable Instruments Marbles hardware has them set to -5vdc to +5vdc. This is easy to fix by using an offset module, however the module uses this signal internally… The bottom line is you can not follow many online tutorials nor imitate many sounds based on the hardware module in VCV.

I also acknowledge that fixing it would break all the current patches. Sigh…

Instead of fixing the existing module and breaking existing patches, couldn’t a new module be added with this fix called Random Sampler 2, and deprecate the previous version?

It matches hardware. Click “Output voltage range mode” to toggle between +2V, +5V, and +/-5V output range.

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Speaking of Marbles, Omri mentioned something about it in a recent stream (think it was the last Q&A) and just said something something is not right with it and you could hear that it was outputting some odd out of scale notes. I’ve experienced this before as well where it seems to drift to a different scale or something. Has anyone pinned this down in order to produce a bug report?

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Yeah, I just could never really have it fit the scale I chose in the context menu. Here it’s set to minor, which I assume is C minor, but there’s an A there.

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Maybe it’s A minor?

There was also a D# (Eb), and an A# (Bb) in there so I’m guessing it’s supposed to be C minor. The Major scale works perfectly though.

From the Marbles manual

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I see it now, on the scope, but the LED’s on the panel never go red like the hardware leading me to suspect the error I reported.

There indeed appears to be a discrepancy in the code between the original hardware and the Audible Instruments versions.

The Mutable Instruments code defines the minor scale as following in settings.cc :

// C minor
  {
    1.0f,
    12,
    {
      { 0.0000f, 255 },  // C
      { 0.0833f, 16 },   // C#
      { 0.1667f, 96 },   // D
      { 0.2500f, 128 },  // Eb
      { 0.3333f, 8 },    // E
      { 0.4167f, 64 },   // F
      { 0.5000f, 4 },    // F#
      { 0.5833f, 192 },  // G
      { 0.6667f, 96 },   // G#
      { 0.7500f, 16 },   // A
      { 0.8333f, 128 },  // Bb
      { 0.9167f, 16 },   // B
    }
  },

While the Audible Instruments code has this in Marbles.cpp :

// C minor
	{
		1.0f,
		12,
		{
			{ 0.0000f, 255 },  // C
			{ 0.0833f, 16 },   // C#
			{ 0.1667f, 96 },   // D
			{ 0.2500f, 128 },  // Eb
			{ 0.3333f, 8 },    // E
			{ 0.4167f, 64 },   // F
			{ 0.5000f, 4 },    // F#
			{ 0.5833f, 192 },  // G
			{ 0.6667f, 16 },   // G#
			{ 0.7500f, 96 },   // A
			{ 0.8333f, 128 },  // Bb
			{ 0.9167f, 16 },   // B
		}
	},

The note A has the weight 96 that can make it happen occasionally, while the weight 16 in the Mutable Instruments code probably makes it almost never happen. It looks like the weights of G# and A have been swapped in the Audible Instruments code. (I assume by accident…)

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I seem to remember discussing the minor scale problem before. But anyway, the reason I found the issue, and I do still think there is an issue, is this video.

The Y output is connected to the Rate input. It’s going + and - 5v. But the notes voltage is 0-2v… So is there a way for the hardware to provide +/- 5v to Y and 0-2v to X’s? Because that’s what’s happening. I finally was able to duplicate the sounds using a separate +/- 5v signal into the Rate input.

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For community review, and thanks for the comments!

Perhaps Marbles really likes the Dorian mode.

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Here was the final version.

The 16 and 96 simply got flipped, yes?

{ 0.6667f, 16 }, // G#
{ 0.7500f, 96 }, // A
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Why would there be any likelihood of A appearing at all in a minor scale which defaults to C?

To jot my listener (singular) back to a conscious state once every so often.

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Because chromatic notes are a thing?

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Sure but it’s generally not desired if something is quantised to a scale though?

who is to say? They clearly think otherwise.