Patch of The Week: 'On the Run' Ep1 Melody - Floyd's Classic Synthi track recreated in Eurorack

video upload by AJH Synth Official

"First of 2 videos showing how to recreate the classic Pink Floyd track from 'Dark Side of The Moon', originally recorded on an EMS Synthi AKS. This first episode covers the sound of the melody and programming the sequence, then Episode 2 (next Sunday) will cover the mysterious percussion (no, it wasn't Nick Mason :P).
In this version just one square wave from a MiniMod VCO is used, and the filter is specifically the Sonic XV, as this is also a 24dB diode ladder filter like the VCF on the Synthi AKS. The only other modules needed are a VCA and an LFO. I also use the Sonic XV's 6dB output - to me this sounds more reminiscent of the Roland TB-303, which actually used an 18dB diode ladder filter, and it gets similarly squelchy with high resonance.
I also experiment using an ADR envelope on the filter frequency - this is a fast sequence, but the Sonic XV responds really nicely to fast envelopes.
Sequencing is courtesy of Doepfer's splendid Dark Time step sequencer, but I also demonstrate using an Arturia Keystep, as this is actually closer to the method used on the AKS version of the Synthi, which came with a digital keyboard sequencer that was significantly ahead of it's time in 1972.

Patch Sheet PDF for this video: https://kvisit.com/8AE/t_kG

Index:
00:00 Intro
00:24 Sequencing with Keystep
00:49 Sequencing with Dark Time
01:21 Sound tweaking
04:28 Patch Sheet

Patch Notes:
Green dots show approximate pot and switch positions. Those with two dots show the range I adjust them during the video. Pots and switches that do not have green dots are not used in this patch, and should be left at their zero or off positions.
SONIC XV: This gets us fairly close to the Synthi's sound, as it shares some lineage from the original diode ladder VCF. I use both 24dB, as the original Synthi filter was 24dB, but also the 6dB output, because in 24dB it is easier to send the filter into self-oscillation when using high resonance, and this sound really benefits from a lot of it. The 6dB can achieve a more noticeable degree of resonance before self-oscillation occurs. It is subjective, and both have their character and strengths, so experiment!
MUTING MIXER or CASCADED VCA: You could also use the Discrete Cascaded VCA for this patch, keeping the Master level high and increasing the Input level until sufficient output volume is achieved. The only reason I used the Muting Mixer here was so I could easily switch between the audio from both 6dB and 24dB outputs of the SONIC XV. If you are using the MUTING MIXER be careful about enabling both inputs at the same time, it will result in an increase in volume, as you are adding audio levels (dB) to each other. It can be very musically useful to do so of course, and worth experimenting with, but bear in mind your overall output level.
Modules used from top-left to bottom-right: Dual LFO + VCA, Vintage Transistor Core VCO, Sonic XV Diode Ladder Wave Filter, Muting Mixer & VCA."