A sampler gives you a list. You pick a kick from it, and if you want a kick halfway between two of them you are out of luck — crossfading two one-shots gives you two one-shots playing at once.
NxD stores a map instead of a list. The sound is a position in it, and the space between two hits is full of hits.
What the map is
Each voice has a trained map of one-shots — a kick map, a snare map — learned as a latent space. A point in that space decodes to a drum hit. Move the point and you move continuously between sounds that were never in the training set but sit sensibly between things that were.
The visual in the plugin is that space, flattened. Those scattered dots are real positions; the one you are on is the sound you hear.
Making it run in real time
Decoding on every hit is too slow to play. The field engine decodes an 8×8 grid once, then bilinear-morphs between cells on the hot path. You get continuous movement through the space without a decode in the audio thread, and the knob moves without flinching.
That is the whole trick, and it is not a clever one — it is just the right place to put the expensive work.
The blocks are the instrument
Underneath the map there are processing blocks, and the point of them is that they do not care where the signal came from:
- Cross-synthesis — the carrier keeps its transients and pitch while the
modulator lends its smoothed banded spectral envelope. Carrier wearing the modulator's coat. Good on attacks, because it preserves them.
- Convolution — a full complex-spectrum multiply, keeping only what is in
both signals. It smears transients, which is bad on attacks and excellent on tails. So that is where it goes.
- Phase-vocoder freeze — hold a spectrum indefinitely. Sustain out of a
drum hit, for drones and chords of frozen drum spectra.
The guiding instinct throughout: use each technique where its artifact is a feature. Cross-synthesis preserves transients, so put it on attacks. Convolution rings and smears, so put it on tails. Do not fight the maths — route around it.
Where it goes
A block should not care whether its input is a decoded neural hit, a folder of one-shots, a MIDI-pitched tom or a guitar plugged into the audio input. They are all just signals. Once that is true the blocks are the instrument and the maps are only one way to feed them.
NxD is coming. There is a look at the panel on the audio page.