Layered synthesised sounds most likely created with various oscillators set to sine wave then parameters tweaked to give it depth and character as opposed to a high pitched beep tone.
I'd recreate it by starting with one sine wave oscillator
Detune slightly
Play with Lfos etc
Add a second oscillator same as above but use the Lfo on a different parameter or 2
Then detune again.
Add some reverb
Set a fast attack on the adsr envelope with a large decay and sustain , play with release until you're happy.
Then you need the high pitch synth layers playing an accompanying melody. Again based on a sine wave at a very high octave, perhaps a lot closer to the original waveform