@marinedalek

4 hours ago
The patch is SYN-LEAD 5 on the DX7. It has specific automation such as vibrato attack and fade-in of the high octave which match the sound on TMS perfectly. FM synthesis generates specific overtones (and more specifically, overtone variation over time) which aren't the same as you would get with a subtractive synth like the CS-15. In fact, the sound is so close that I was able to compare it with my own DX7 and find that TMS was originally recorded 1 semitone higher than it was broadcast. The 10kHz line shows that the tape is a faithful reproduction of the pitch-as-broadcast, but the vibrato of the DX7 part is very slightly slower on TMS than on the original synth. The difference in frequency works out to exactly a 1 semitone shift. This wasn't unusual - several ABBA songs were completely finished and then pitched up or down with varispeed during mixdown to get a certain feel. Also the 1980 Doctor Who theme was recorded a semitone flat from the final master, but it was pitched up for broadcast/album release because the multitrack sounded too slow and plodding.