Boards of Canada - "Wildlife Analysis" Lead by Synths of Antarctica
The 3340 VCO's make it possible to imitate many of the Boards of Canada lead, pad and bass sounds. One of their synthesizers included the Roland SH-101 having the original Curtis 3340 VCO chip.
Using only OSC1 in Paraphonic mode as the Porta Time seems to sound just right. Attenuator 1 on my synth is a little sensitive so adjust carefully to get the perfect tape machine wow effect. Hope you enjoy!