New filter

Now that I got rid of my DIY-101 based on Doepfer DIY, I'm back to a one filter configuration.   And that filter, Ripples, does not have a high pass output.  I was in need of a new multimode voltage controlled filter and I chose Erica Synth Multimode VCF kit.

Multimode VCF

This is another straightforward kit.  It is rather dense, despite being comprised of two boards.  The kit comes with three bags of parts : one for each board then there is the traditional potentiometers and jacks.

The kit

Sorting parts

Bob cuts resistors legs

The documentation (online, once again) is heavily illustrated and pretty complete with schematics and placement files.  No step by step instructions though.   Just photos of boards at various steps.

Boards are dense but perfectly labeled.  I noticed a single mistake : boards label called for 51k resistors and I received 56k (or was it the other way around ?).  I reckon a 10% difference is no problem.

This went like a breeze.

Main board, chilling on the bench

Odd capacitor placement

One oddity though is the fact that the boards are so heavily packed, they felt the need to solder the electrolytic capacitors upside down on the control board.  Two of which have to be bended parallel to the PCB because the main board will be above them. I put some insulation tape between the board and the capacitors despite the fact there is no indication to do so.  Better safe than sorry.

These capacitors have to be soldered the last according to the manual.  But I would rather put them after the standard parts and before the jacks and pots : once they are put in place, it is quite full.



Anyway, here it is, mounted in the synth.  That first row is now nearly set.

One thing I found a bit odd with this module is the placement of the potentiometer.  I would have put the c-off cv and reso cv close to the corresponding jacks, same with the audio level.  So I would have preferred an inversion of the two rows of potentiometer.  I would have found it more logical.

VCF in place

I do not have any 2 HP blank.  A clear oversight from my side.  I now have that small 1cm gap between the Mammouth VCO and the Erica Synth VCF.  It is supposed to be filled later with a 2 HP multiple.

So, here is a small piece of sound from the synth as it is.





Two tracks recorded live from the modular. Each track is sequenced by one channel of the Korg SQ-1.

DAW : Reaper

Usual effects : TAL Dub II, NI Supercharger, Voxengo OldSkoolVerb, Thomas Mundt LoudMax.

Bass voice : saw and square from Doepfer VCO to Erica Synth VCF Low Pass directly to VCA. Modulated by envelope from Befaco Rampage. Very standard.

Drum voice : mix of two parts.

1. Ripples pinged by Rampage, modulated by second envelope of Rampage and sequencer.

2. Rings, same trigger, same sequence.

Ripples

My latest acquisition from Mutable Instruments is the Ripples filter.

Ripples unboxed.

With only one filter in my rack, it was not easy to have more than one interesting voice at a time. 
So I thought I needed another one to extend the capabilities of the synth.

Bob pushes modules around to make some room in the rack

For me Ripples has three main advantages :

• I like the designs from Mutable Instruments;

• it's a 4-pole 24 dB/oct filter and complements the 12dB/oct from the Doepfer DIY;

•  it includes a VCA and it's a precious space saver in a small system like mine.

In the rack

There are 3 CV inputs : one for resonance and two for the frequency.
There are 3 filter outputs : 2-pole band-pass, 2-pole low-pass, and 4-pole low-pass.
The 4-pole low pass through the VCA is the latest output.

Getting Ripples and the Turing Machine change my initial plans a bit.
But that's the principle of having a modular synthesizer I guess.

It begins to take shape…

In the track below, hihat is white noise from the Random Module into the high-pass Doepfer fllter then on the VCA driven by the channel A of Rampage.
Kick and other percussions are from the same noise source into Ripples and on the VCA driven by channel B of Rampage.
Melodic lines are sine from Doepfer VCO into VCA driven by the envelope from Doepfer DIY, then passed through the phaser.
Sequencing wise, the first channel of the Korg SQ-1 triggers the hihats and serve as clock source for the Turing Machine.  CV out modifies the length of the rampage envelope to get longer hihats at times.
The second channel triggers kicks and other percussions.  Different percussions are obtained by modulating the frequency of Ripples.
Finally, driven by the clock from the first SQ-1 channel, Turing Machine provides gate and random notes CV (tuned by 2hp Tune) for the melodic lines.



DAW: Reaper
This is a single track from the synth plus a bit of chorus, delay and reverb.