2FM2 - A Full 2OP Synth for NTS-1 - Demo Jam

video upload by ChrisLody

"If you'd like to support the channel you can grab a 'Pay What You Want' album from my Bandcamp. https://chrislody.bandcamp.com

Dowload 2FM from: https://github.com/ChrisLody/NTS1-2FM
Grab the two .ntkdigunit files and add them to your NTS1 using Korgs librarian software.

So full disclosure, this pair of custom oscillators was vibe coded. I am learning a bit about coding, but I'm no way near good enough to put this together without some help. I've wanted someone to make an FM synth for the NTS1 for ages and nothing has quite hit the mark, so I decided it was time I did it myself.

The 2FM comes in two flavours, 2FM1 and 2FM2.

2FM1 is designed to be a basic FM tone generator while 2FM2 includes a modulation envelope.

Both feature a modulation level on the A knob, bipolar feedback on the B knob, then Ratio and Fine controls in the custom oscillator settings that can be accessed by holding OSC and turning Type.

2FM2 goes a step further by adding an ADSR for modulation to the custom controls.

The reason for this is that the NTS-1 will always reset its knobs to minimum as its powered up, and with the ADSR as minimal settings it has no affect and therefore there is no sound of FM without tweaking the envelope. This can be a bit confusing so the 2FM1 version is a kind of beginner mode, 2FM2 is more advanced.

You can set up a tone on 2FM1 with the A and B knobs, then these will be remembered as you change over to 2FM2 to adjust the ADSR.

There is no carrier envelope as the same thing can be accomplished using the standard NTS1 envelopes. You can also route the NTS1 LFO to mod level or pitch so no LFO was included in the custom oscillator either. So between the custom settings and the standard NTS1 architecture, that's a pretty fully featured FM synth! Just a shame the NTS1 is mono.

All sounds in this video are made using 2FM2 with no filtering used. There are some effects on in a few places but that's about it."