Variable pulse width
Low-pass filter with adjustable resonance
c = Click
Extra-resonant bandpass filter for 808-like drum sounds
n = Noise
True analog noise generator or
Dual square waves
Bandpass filter with medium resonance
On the original Game Boy models, one pin of the cartridge connector functions as audio input, connected to the built-in amplifier. This unique feature allows to generate sound on the cart and play it through the headphone output on a completely analog signal path.
In the nanoloop mono cart, the analog components (op-amps, comparators, logic cells etc) of a PIC microcontroller are connected and configured in such a way that they form a hybrid soundchip with 3 analog filters and a true random noise generstor, using only a few passive external components.
The cart is a flat but very robust PCB with all electronic parts embedded.
Nanoloop mono is a stepsequencer with per-step control for all parameters. There are 8 banks of flash memory each of which can hold 15 patterns per channel and a song structure.
works, but very little / distorted bass, a lot of hum and whine
Game Boy Advance
doesn't work, cart won't even boot
Allthough amplitudes are the same as with internal sound, with nanoloop mono's softer characterisic, differences in audio quality are more noticeable.
Some improvement is possible by adding capacitors to the Game Boy's main board ("bass mod" and "noise filter mod"). However, GB Pocket will still produce a high-pitched whine and GB color will still hum and distort basses.
In conclusion, only the original Dot Matrix Game Boy can be recommended.
Nanoloop mono offers the same sync options as nanoloop one.