Analog Modular

PugixWelcome to my DIY synthesizer website. The name Pugix (and the graphic toon) belonged to an online gaming character that I used to play and has nothing to do with synthesizers.

My most recent activity:

Sidrazzi Ditty

Something else I’ve been playing around with:  Sidrazzi with Cocoquantus modulating it to get random S&H steps.  Processed by the Deflector Shield and the Re-sampling Mini-Delay.  This is entirely performed.

Big Envelope

Trying an idea from David Linton, who asked, What if you mixed all your oscillators, tuned to the same pitch, in one patch.  I didn’t use all 15 of my 1V/octave music VCOs in this mix, but just 10, each followed by a separate VCF with a fixed cutoff.  During the recording some waveform changes were manually made.  The name comes from the fact that the whole piece is ‘enveloped’ by manual attenuation.  This is a short recording.  If I did it live, I would probably stretch it out.

E560-E580 Drone

Here’s a quick patch I did with my new Synthesis Technology E560 Deflector Shield and E580 Re-Sampling Mini-Delay.  Just those plus two oscillators and one sample and hold.  Recorded on the Zoom H2n in my studio space.

Synthesis Technology E580 Sampling Mini-Delay

motm-e580-panelQuantity: 1

The Synthesis Technology e580 resampling mini-delay emulates the classic sounds of digital, bbd and tape-based delays with four parameters under voltage control. The E580 recreates the pitch-shift modulating of bbds with the variable bandwidth and noise floor without costly bbd ics. In tape mode, wow& flutter, tape saturation and non-linear distortion model classic tape units without the bulk and maintenance.

There are two simultaneous audio outputs: a straight delay and a variable tapped delay. The tap position is a percentage of the main delay time. This allows very short delays (<350us) as well as long delays (750ms). Both tap position (‘offset’) and main delay time are voltage-controlled over a -5v to +5v range.

The feedback is jumper-selectable from either the tapped position or the main delay. This flexibility can generate standard ‘rhythmic’ delays (feedback from main delay) or a series of ‘pre-delay reflections’ (tapped delay) which sound very different from each other.

Enhancements:

  • Addition of five attenuator pots:  one for each CV input, plus one for the signal input
  • Addition of a panel switch to replace the PC board jumper to select the feedback source

Construction:

Please see the previous post for details common to this and the DIY E560 project.

As mentioned in the previous post, the biggest challenge was mounting the PC board to a bracket.  As shown in the following picture, the bracket was fabricated from thin aluminum stock, available at any hardware store.  The bracket mounts to the panel beneath three pots.  Six of the holes which formerly mounted the pots to the board were re-purposed as mounting holes for 3-48 screws.  Although this left the end of the board with MTA connectors a bit cantilevered, after installation there is no pressure on the board.  But one must be careful when plugging in the connectors.

Four pots from the board were installed on the panel, as well as five attenuator pots, each between an input jack and an input on the board.  These attenuators really enhance the ease of use for CV and also especially for attenuating the audio input signal to avoid overloads.  I chose Bourns pots from Mouser, part #652-91A1A-B24-A20L.  The MTA headers and mating connectors are Mouser parts 571-6404543 and 3-640441-3.

e580-assembly

Please see Dave Brown’s E580 DIY project for comparison.

Here’s a demo of a little patch I did with it.

 

E560-E580 Project

I was late to make DIY builds of the Synthesis Technology e560 and e580 modules.  A post on the Synthtech email list alerted me to Dave Brown’s builds.

E560 Deflector Shield

E580 Resampling Mini-Delay

I had heard about these DSP modules when they came out about three years ago in Eurorack format.  I didn’t know that Paul Schreiber was still offering the DIY kits in summer 2014, but he was and I purchased one each.  I obtained the excellent Front Panel Express panel files designed by Dave Brown and ordered those, too.  The only remaining parts for the project were panel jacks,  attenuator pots, knobs and one switch.  Here’s a photo of the assembled and tested boards, as delivered from SynthTech:

e560-e580-boardsFour pots and one switch are soldered onto the board and serve to mount it behind the standard Eurorack panel, like so:
e560s

Putting these into 5U panels required removing the switch and pots from the boards. After a struggle with the first pot, I developed a technique to suck solder out of the holes around the mounting table and then rock them out gently, after desoldering or cutting the leads. Like Dave Brown did, I installed 3-pin MTA headers to make all connections to the panel, so that no wires would have to be soldered to the PC boards.

The trickiest part was finding a way to mount the board to a bracket, since the boards have no mounting holes. Dave had drilled corner holes, but I deemed that too much risk of damage to the multilayer PC board. Instead, I used six of the holes that formerly held the pot tabs and found that size 3-48 screws from Ace Hardware were just small enough to tap into them without much fuss. (A 3-48 screw is in between a 2-56 and a 4-40 in diameter.)

Here’s a photo of the empty panels:
e560-e580-panels

Here are all the parts laid out, prior to assembly.
e560-e580-big-parts

Subsequent posts will describe each of these modules in detail.

Time is a Wave Performance

Live space recording of my performance at the Time Is A Wave event in Marshall, NC.  I used the Quantisise as a pattern generator to control the pitches and levels of two oscillators.  It started it dry and then I added a sequence of treatments that were worked out in advance.  There is some indistinct chatter going on throughout.  I intended that it would start out at low, ambient volume, so I expected some chatter.  But it seems that some in the audience never detected that a performance was going on until it was over.  Perfect!  Listen for the train horn blast around the 10 minute mark, as a freight train roared by.