Ok, let's spill it here before I spill on Twitter (it's a great article BTW

):
Composite Bass
"The bass part was done with three synths MIDI'd up: DX-7, Jupiter 6 and the Emulator II. The DX-7 voice was a very low pitched, percussive sound; it didn't have much of a note but it gave the thing depth and attack. The Jupiter provided the body of the sound, and the Emu II was actually playing a bass drum sample, the pitch of which changed as it was played on the keyboard to add some punch. Getting that sound took some time, and Steven also wanted it to be played by hand, rather than using a sequencer, because he felt that it would lend more fluidity to the track. It was a bit of an ordeal getting it in time with the drum machine, but I think in the end he was right and it sounded very good.
Here's the track list:
So - DX7 (I mean, 1984/85, there's going to be one lurking about somewhere!) & Jupiter 6!
Jupiter 6!!
Given that this interview was done in 1986 by the house engineer who tracked and mixed the song, just a year after it was made, and the engineers tend to have a better handle on the gear that was used during sessions, I take this info as more reliable than Stephen Hague's "from memory it was an OBX" from 35 years later - although the other recollections about playing by hand etc match up.
And I always remembered this section of the article:
"Another element in the track is the traffic noise which Steve simply recorded on a Professional Walkman, with Dolby C, out in Gosfield Street where Advision is. Just across the road is Wham's office and there were dozens of young girls milling around when Steve was recording. Steve looks a bit like Sting and so you can hear on the tape the girls shouting "It's Sting, it's Sting". Also, one of them was singing Careless Whisper, which coincidentally was perfectly in tune with the track; so you can hear that too at the beginning of the record, just before the drums come in.
I read this issue of this mag so many times back in the day, that just seeing the scans again is quite remarkable how much each page was lurking in my mind somewhere.
So, another mystery solved.
The full article will of course be up on mu:zines at some point.