Uploaded September 2024 | Updated September 2026, 1 week ago
Demonstration of the duty cycle clock speed trick described in an earlier video.
By changing the percentage of on/off in a volume modulation envelope which cycles at audio rates, you can create 12.5%, 25%, 50%, and 75% squares, or sweeps through the duty cycle range, like a 2A03. This is also how the lower-than-A2 pitch is achieved, rapidly modulating the volume of the channel to give the illusion of a lower octave.
Note: I'm using Chipsynth MD which allows you to modulate the operator level at extremely high rates. This is not possible in vanilla Furnace (but probably possible if you change the max rate in a fork) but is possible on hardware, as the rate of modulation is in the kilohertz while the SN74689 can be externally clocked in megahertz, meaning it's well within the speed that could be handled by a game's sound driver.
VGM Sources server: discord.gg/m4qzYNGHuS
Ko-fi: ko-fi.com/nuclearmusic
Note: This Ko-Fi is for helping fund the acquisition of new musical instruments and equipment, not for any specific project I do.
Demonstration of the duty cycle clock speed trick described in an earlier video.
By changing the percentage of on/off in a volume modulation envelope which cycles at audio rates, you can create 12.5%, 25%, 50%, and 75% squares, or sweeps through the duty cycle range, like a 2A03. This is also how the lower-than-A2 pitch is achieved, rapidly modulating the volume of the channel to give the illusion of a lower octave.
Note: I'm using Chipsynth MD which allows you to modulate the operator level at extremely high rates. This is not possible in vanilla Furnace (but probably possible if you change the max rate in a fork) but is possible on hardware, as the rate of modulation is in the kilohertz while the SN74689 can be externally clocked in megahertz, meaning it's well within the speed that could be handled by a game's sound driver.
VGM Sources server: discord.gg/m4qzYNGHuS
Ko-fi: ko-fi.com/nuclearmusic
Note: This Ko-Fi is for helping fund the acquisition of new musical instruments and equipment, not for any specific project I do.
