Lace

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  Wedge of Cheese

• Dec 26, 2011

http://www.mediafire.com/?lqqf5h2tld65k8t

This is what the output from our example sounds like at the typical sampling rate of 44100 sample frames per second.

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  Wedge of Cheese

• Dec 26, 2011

In Pixel's pxt editor, he calls it a ramp. I sometimes like to call it the "stock market waveform".

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  Wedge of Cheese

• Dec 26, 2011

This waveform, where it rises and then suddenly drops repeatedly, is fairly common and is called a sawtooth wave.

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  Wedge of Cheese

• Dec 26, 2011

In other news, I probably should have just written a program to generate that image rather than slaving away in mspaint for a half hour... >_>

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  Wedge of Cheese

• Dec 26, 2011

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  Wedge of Cheese

• Dec 26, 2011

So, suppose the inputs were: "pitch=.08, volume=.5". The graph of the output over time would look like this:

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  Wedge of Cheese

• Dec 26, 2011

Finally, the state is outputted.

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  Wedge of Cheese

• Dec 26, 2011

The state is then updated to fit within the interval [0,1) by repeatedly adding or subtracting 1 (i.e. 1.3 becomes .3, -.4 becomes .6, etc.).

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  Wedge of Cheese

• Dec 26, 2011

It has an internal state which is also a numeric value in the interval [0,1). During each virtual "clock cycle" of the synthesizer (each of which corresponds to exactly one sample frame of audio output) the input value is first added to the internal state.

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  Wedge of Cheese

• Dec 26, 2011

The output of an oscillator (at least in the way I'm defining it for now) will always be in the interval [0,1).

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  Wedge of Cheese

• Dec 26, 2011

Multiply should be pretty self explanatory. Its output is simply the product of its inputs. Oscillator is a bit more complicated.

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  Wedge of Cheese

• Dec 26, 2011

As you can see, there are two devices in this synthesizer, called multiply and oscillator.

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  Wedge of Cheese

• Dec 26, 2011

A very simple synthesizer might have a block diagram that looks like this:

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  Wedge of Cheese

• Dec 26, 2011

We'll do this using block diagrams. A blue block represents an input to the synthesizer, a green block represents an output of the synthesizer, and a red block represents a device.

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  Wedge of Cheese

• Dec 26, 2011

Before we get into the details of coding this in Java, let's try to get a conceptual picture of it.

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  Wedge of Cheese

• Dec 26, 2011

Each device would have some number of inputs (either other devices or inputs to the synthesizer) and one output (either another device or an output of the synthesizer).

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  Wedge of Cheese

• Dec 26, 2011

Such a synthesizer would have any number of inputs, 1 or 2 outputs (depending on whether or not I want stereo sound) and several "devices" in between to do the calculations.

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  Wedge of Cheese

• Dec 26, 2011

Alright, so aforementioned attempts at synthesizing audio from scratch and outputting results to a wav file consisted of building virtual synthesizers.

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  Noxid

• Dec 25, 2011

Merry Merry!

If you might remember, last year there was a Cave Story Christmas image ft. various sprites like Santa Santa and Elf Booster and Reindeer quot. I based my avatar off the sprite in that original image.

• 

  Wedge of Cheese

• Dec 25, 2011

Tomorrow and day after, there will be postathon. Lots of it.