Additive, Multi-Voice Synth Preserves Sounds, Too

January 13, 2020 by Kristina Panos 2 Comments

For his final project in [Bruce Land]’s microcontroller design class, [Mark] set out to make a decently-sized synth that sounds good. We think you’ll agree that he succeeded in spades. Don’t let those tiny buttons fool you, because it doesn’t sound like a toy.

Why does it sound so good? One of the reasons is that the instrument samples are made using additive synthesis, which essentially stacks harmonic overtones on top the fundamental frequency of each note. This allows synthesizers to better mimic the timbre of natural, acoustic sounds. For each note [Mark] plays, you’re hearing a blend of four frequencies constructed from lookup tables. These frequencies are shaped by an envelope function that improves the sound even further.

Between the sound and the features, this is quite an impressive synth. It can play polyphonically in piano, organ, or plucked string mode through a range of octaves. A PIC32 runs the synthesizer itself, and a pair of helper PIC32s can be used to record songs to be played over. So [Mark] could record point and counterpoint separately and play them back together, or use the helper PICs to fine-tune his three-part harmony. We’ve got this thing plugged in and waiting for you after the break.

If PICs aren’t what you normally choose, here’s an FPGA synth.

Continue reading “Additive, Multi-Voice Synth Preserves Sounds, Too” →

Black MIDI: There Is No Denser Music

November 12, 2015 by Elliot Williams 73 Comments

Imagine if you played all the keys on a piano at once. What would it sound like? Now imagine that you’d like to transcribe that music. What would it look like? So many notes that you could hardly see the paper underneath.

Which is why the people making such “impossible music” are calling themselves the Black MIDI Crew: if you wrote the music down, it’d look like a big black blob. Or at least, that’s the joke. Amazingly, though, it doesn’t sound like a big mess. Check out “Pi, The Song With 3.1415 Million Notes” below the break to see what we mean.

Continue reading “Black MIDI: There Is No Denser Music” →

Building The Ocarina Of Time With An FPGA

December 13, 2011 by Brian Benchoff 8 Comments

[Joe] and [Evan] wanted to have some fun with their FPGA course at Cornell. When faced with what to do at the beginning of the semester, they figured additive synthesis was a worthy pursuit. They ended up building the Ocarina of Time for their final project.

The guys started by recording a real ocarina and figuring out the relative power levels of each harmonic. Because any sound can be synthesized from a bunch of sine waves, having their Altera FPGA board replicate those frequencies produces a nice ocarina sound

[Joe] and [Evan]’s ocarina has a ‘mouthpiece’ that is just a small microphone. This mic is hooked up to the FPGA board and controls the volume. Sadly, the guys didn’t have time to take apart an N64 controller so 6 red buttons serve as the finger holes.

From the video after the break, [Joe] and [Evan] really pulled together something that sounds like Link’s Ocarina. Great work, guys.

Continue reading “Building The Ocarina Of Time With An FPGA” →