Everyone's gonna tell you that it's a generic pluck arp, but to be honest, it's not so easy to make such a pluck sound so nice as in the clip you posted.

It's a bunch of detuned saws, with a proper amp and filter ADSR, probably a lil' bit of pitch LFO and pitch modulation (on decay). Maybe some overdrive to it? Or bitcrushing? I really don't know There are some similar presets for Discovery VSTi from Vengeance.

i know this track... could you share the name? everything i could tell you about sound designing would be mediocre so i'd better not say nothing.

Zebra 2 makes plucks that sound alot like this

What synth plugins do you use? If you use, Sytrus, 3xOsc or any other FL native plugin. I can be in your assistance.

If you don't have any of that stuff, you can always go after Matt's description, it's easy to do something like this on any proper synthesizer, hardware as software.

Also, I'd suggest you to put in unison and chorus effects to make it richer. Putting on delay and reverb removes that awful-sounding isolation, if you know what I mean. Lastly, put on some flanger or phaser or whatever, to make it seem less generic and more of a sound you invented yourself.

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