AndreasKrebsBlog

This is an easy listening tune. Some modular synth drums, some Karplus-Strong sequence, some ladder filtered bass, lots of fun!

We start with “Hihats”: A-117 Digital Noise put into an A-106-5 SEM Filter (highpass mode) and then into an A-131 VCA. Both VCA and filter controlled by an A-142 VC Decay, which is triggered and controlled (decay length) by an A-155 Sequencer.

Then we have some (tuned) “Snare Drums”: A-118 Noise (coloured noise) is first put into an A-127 VC Resonance Filter and then into an A-132-3 VCA (controlled by a snappy A-140 ADSR) and then into an A-188-2 Tapped BBD. The BBD is used as a device for Karplus Strong synthesis: Delay frequency is controlled by another A-155 Sequencer (driven by an A-154 Sequencer Controller) and A-156 Quantizer. When put into feedback resonance, the BBD will produce tonal results, triggered by the noise input. The two BBD outputs are fed into an A-101-3 Modular Vactrol Phaser (controlled by two LFOs from an A-143-3).

The “Bass Drums”: White noise from an A-118 is fed into an A-106-6 XP VCF.  The 2 pole LP output is sent into an A-132-3 VCA, both filter and VCA are contzrolled by an A-140 ADSR, triggered by an A-155 Sequencer.

The “Bass” is simply three A-110 VCOs (trinangle 1 oct down and two sqare waves) put into an A-108 ladder VCF. Both square waves are PWM modulated by two triangle LFOs (A-143-3). The 24dB filter output is fed into an A-132-3 VCA, filter, VCOs and VCA are controlled by an A-155 Sequencer and A-156 Quantizer (the same sequencer that controls the BBC frequency). The A-154 Sequencer Controller is in “pendulum” mode, which is changed manually during the track, as well as starting and ending step (around 4:00). 

Finally, there’s some FX from Ableton Live and some mastering in Cubase 5.5. No overdubs, everything is improvised.

Here we go:

 http://www.andreaskrebs.de/assets/media/improvisation-20100627a.mp3

Track length is 09:49.

Have fun, 

Andreas

Well, we probably all know the sound of a phaser. Nothing too special, although there are some famous ones around. Just one of these beautiful additional effects. The A-101-3 can do more. It offers access to inputs and outputs of all 12 shifting stages and it allows for different modulation sources for stage 1-6 versus stage 7-12.

Technical details can be found on Doepfer’s Homepage:

http://www.doepfer.de/A1013.htm

So I have set up a little patch to create quite wild things: three A-110 VCOs (sawtooth, one VCO is tuned down 1 oct), mixed, amplified (with an A-132-3, controlled by an A-140 ADSR) and then split (via multiple) to be put into stage 1-6 input as well as into stage 7-12 input of the A-101-3. VCO frequency and ADSR are controlled by an A-155 Sequencer. Stage 1-6 shifting is modulated by one triangle LFO (A-143-3), stage 7-12 by a different triangle LFO. LFO frequencies are changed manually during this recording.

Now here comes the fun part: shifting stages outputs 5, 6, 9 and 12 are fed into an A-138m 4×4 Matix Mixer. The four outputs of the matrix mixer (all four in bipolar mode) are fed into shifting stage inputs 1, 6, 7 and 12. This allows me to create feedbacks, feed-forwards, inverted feedbacks and inverted feed-forwards in quite complex combinations (and some really weird sounds). The two final outputs of the phaser are simply left and right audio channels with original/shifted signal mixed 50:50. Since the resonance of vactrol devices can be quite loud, I’ve put some compression and limiting on the track.

Here we go:

http://www.andreaskrebs.de/assets/media/A-101-3.mp3

Andreas

This is quite a retro sounding piece and my Kotau to the great Berlin School in the 70ies. Great Artists! (Edgaer Froese, Klaus Schulze, all the others)

We start with some noise (A-117 Digital Noise output) put into a A-101-1 Vactrol VCF. The filter is near self oscillation and is modulated by an A-155 Sequencer. We go into an A-132-3 VCA, modulated by an A-142 VC Decay.

Then we have a traditional electronic “bass drum”. This is an A-106-6 XP VCF, self-oscillating and with some white noise input from an A-118. To add some dirt, I put the result through an A-136 Waveshaper. The A-106-6 is modulated by an A-140, which also controls the A-132-3 VCA.

Next we hear some “snare”, whatever, percussion sound. This is a bit more complicated: Sound source is coloured noise from an A-118, put into an A-124 Wasp Filter. Then I put the result into an A-127 Triple Resonance Filter. After this, the result is put into an A-132-3 VCA (both Wasp Filter and VCA are modulated by an A-140 ADSR). We’re not finished yet. Then we go into an A-188-2 Tapped BBD, and with both outputs into an A-134-1 Panner - modulated by an A-147 VCLFO, which is reste by the master A-154 sequencer clock, divided by 8 with an A-160 Clock Divider. Complicated snares, eh?

The sequenced bass lines are quite straightforward: two A-110 VCOs (square wave and triangle wave 1 oct down) go into an A-108 Ladder Filter (in bandpass mode). Then into an A-131 VCA (which sound more “retro” than the hifi-alike A-132-3). Both filter and VCA are modulated by an A-140 ADSR. The filter is also modulated by the A-155 Sequencer (same sequence as for the VCO pitch).

This bass line is doubled (i.e. another two A-110s and another A-108 and A-140). Both voices are separated a bit in stereo. I use one A-155 for the two bass lines (two separate rows through an A-156 Quantiser) and another one for triggering bassdrum (XP Filter) and snare drum (Noise through Wasp Filter). The A-154 Sequencer Controller for the bass lines is modulated in “first” and “last” step, the sequencer controlling rhythm is reset by some combination of trigger / sample and hold and trigger delay (being “nearly” random). The additional digital noise is triggered by a combination of A-160 Clock Divider, A-161 Clock Sequencer, A-165 Trigger Modifier and A-186-1 OR-Combiner.

Both bass lines are transposed manually (with an LMK2+ through a Kenton Pro-2000 MkII) and there is some Melotron sound by  GForce M-Tron.

As usual, there are no overdubs, everything is recorded “live”, with some additional reverb, delay in Ableton Live, some slight distortion with NI Guitar Rig and mastering in Cubase.

Here we go:

http://www.andreaskrebs.de/assets/media/improvisation-20100620a.mp3

Track length is 13:29. 

Have fun, 

Andreas

This is an extreme filter. Pure rock and roll. Doepfer has created a beautifully distorting nonlinear monster, inspired by the Korg MS-20 filters (a 6 dB highpass and a 12 dB lowpass filter). Both HP and LP modes are available simultaneously (via normalized input jacks). The “real deal” however will need two A-106-1 filters: this allows for independent filter frequencies for HP and LP.

We start with the usual three A-110 VCOs (all saw outputs, one of them transposed 1 oct down), go into the first A-116-1 (using highpass mode) and then into the second A-106-1 (using lowpass mode). Pitch and ADSR trigger are controlled by an A-155 seqencer. Different clipping levels were used (manual control). For technical details of the A-106-1 Xtreme Filter take a look at Doepfer’s Homepage:

http://www.doepfer.de/A106.htm

During the first 2 minutes, only a single A-106-1 is used, then we switch to two (HP first, then LP) filters. Here we go with the example sound:

http://www.andreaskrebs.de/assets/media/A-106-1.mp3

Andreas