Saturday, June 22, 2013

Using the Doepfer A-155 to Re-arrange Audio

   After thinking about the differences between the currently available Doepfer sequencers, I decided to try out a patch which would randomly switch between free-running beat loops using the inputs to Row 2 of the A-155, a feature unique to the A-155 in the Doepfer range.  
   Have a look at the video below and follow the LEDs of the top of the module.  You will notice that each step plays a different AUDIO beat loop. 

A-155 as Beat Slicer from N K on Vimeo.

about this patch....

  To make this patch, I took eight individual drum loops from old tracks of mine and loaded them into Ableton Live.  Each loop was routed to a separate mono output of my MOTU 24I/O soundcard, and from there patched directly into the sockets on the bottom of the A-155 module.  A few of the loops got some effects applied to them in Live, modulation effects like flange, so each time that beat is heard it is at a different point in the flange sweep.  What you are hearing is the CV output of the sequencer....which would normally be a set of DC voltages for controlling pitch of a VCO, etc.  But in this patch, the output is actually audio.  By patching into the lower row of sockets, you interrupt the voltage being sent to the Row 2 CV controls, which now act as volume controls for each input signal.  

  This beat-switching effect is not wave-sequencing, because each new step does not re-trigger the selected drum loop.  Instead, all of the drum loops are always playing in sync, and the sequencer is choosing which one will be heard at any given moment.  The result is similar to a DJ cross-fading between two beat-matched records, except there are eight records!  This patch is in no way restricted to beat loops, as any signals can be sequenced with this method:  different LFOs, eight more A-155s (yes!), pads, vocal tones, sound effects and drones, arpeggio loops.....

  The sequencer's audio output was processed with an A-109 Signal Processor with S+H to cutoff with some resonance with manual adjustment of the A-109 and A-199 Spring Reverb.  

Another example....

  Here's another example using the Doepfer A-155 Sequencer to manipulate audio signals.  This time I used some Jungle/DnB loops, and none of those loops were processed pre-A-155 unlike in the previous example.  I thought more "realistic" sounds might make it easier to hear the loops change.

A-155 Jungle Sequencer from N K on Vimeo.

  This patch was very similar to the first, using the same trigger pattern to control the sequencer clock and the S+H filter effect.  The A-155 has two CV outputs per row, Pre and Post, which in this case are the same signal.  Pre Out went straight to the mixer, and Post Out was split to the A-109 with S+H and an A-124 Wasp VCF with FM (fast modulation from an A-110 VCO and slower modulation from an A-145 LFO).  Both filtered versions were added to the Pre Out signal with an A-138 mixer, boosted with an A-119 Ext Input, and sent to an A-199 Spring Reverb.  Some manual adjustment of Wasp FM, A-109 Fc/Q, and Reverb Mix was made during recording.  

1 comment:

  1. hey, Great Patch! really inspiring and relevant to the sort of things im trying in my music at the moment.