There are a number of dedicated trigger sequencers on the market today aimed at making it easy to create drum patterns for your modular. But, … I don’t have one. I do, however, have some other analog sequencers that can be coaxed into creating trigger patterns which range from standard 4/4 beats to complex, evolving rhythms. Below is one example of such a patch, focusing on the features of the Doepfer A-154/155 Sequencer and Controller combination.
The drum sounds:
I made some drum sounds with my modular for this example. The “Kick” is made with a Doepfer A-102 Diode Filter, with the resonance set to self-oscillation. The trigger for the kick goes to two ADSR modules, one for the VCA after the filter and one for the filter cutoff to create the drum’s percussive attack. The “HiHat” is the closed hat sound from an Analogue Solutions HH88 module, with some Analogue Solutions SR01 Spring Reverb (original version). The “Snare” is the digital noise output from a Doepfer A-117 Noise/808 Source module filtered by a Doepfer A-121 Multimode Filter with LFO modulation, using the BP output with some A-199 Spring Reverb.
The A-155 analog/trigger sequencer:
|Trigger routing switches|
The A-154 Sequencer Controller:
|A-154 Manual and CV controls|
These two LFOs are almost fully to the right of the middle row of modules pictured in the video example, and you can just make out the lights corresponding to the snare rolls and random fills. Both A-146 LFOs are shown circled yellow in the image to the left. The leftmost is in its "high" state (LED is lit), and you can see that the A-155 is therefore in the Random play direction (circled orange).
Driving the A-154/155:
|Ext clock and reset inputs|
Note: Using the MAQ in this patch may seem like a waste of sequencer power. However, the MAQ makes this patch able to make rhythms that are infinitely more complex than the one shown here. The MAQ row being used as the "clock track" could have rests, could be a length other than 16 steps, and could have its own timing controlled by the third MAQ row! You might have a 5 minute song with no 2 bars the same!
Additional noises in the example:
|CV sequence row|