Monday, 31 July 2017

Serge Bi-directional Quad switch - build notes

I've been searching for the perfect synthesizer router for my Serge.
The Serge Bi-directional router is fine but I would love to have more ins/outs.
Recently I built a NLC 32:1and NLC Router for Eurorack.
All excellent and I might one day adapt one for the Serge.
One I haven't tried is the serge Quad switch which seems to be an adaptation of the earlier
Serge Triple Bi-directional R.

The module I'll build is the Cat Girl Synth CGS 88.
Ken's Build notes are here:

The Quad switch uses a CD 4013B.
Its a CMOS Dual D-type flip flop that works as a two bit binary counter.
Looks like the switch used in the vintage 1970's module was a Motorola MC14007UB.
It was mounted on a separate board off the original R4 PCB.
You can still find these.

D = Drain, S = Source.

to be continued..... waiting for parts.

Sunday, 30 July 2017

Router - NLC build notes

Some build notes for the Nonlinearcircuits router.
I'm hoping this will function something like the Serge bi-directional router, but with 4 outs rather than two.
A router can also be found in the NLC Chopper.

The new NLC Router is a voltage controlled switch that can deliver 1 into 4, 4 into 4 and 4 into 1 at the same time, 2x 2 into 2 and, with a simple mod to the PCB, 2x 1 into 2 

This looks like a easy build.
ICs on first.
The module uses a DG412 which is a CMOS analog switch.

Control inputs are pins 1,8,9,16 (in)
D1–D4 : Analog Switch Drain Terminal
 S1–S4 : Analog Switch Source Terminal

Passives, resistors, diodes, caps
The thru hole stuff.

Jacks & pots.

Input 1 is internally connected to the switches on jacks 2, 3 & 4.
CV 1&2 is internally connected to the switch on the CV 3&4 jack.
The signals to the OUT ALL jack are summed together

The Router pots can be used as switches, 0 is off and 10 is on. At these settings the switches will ignore incoming CV or gate signals. For the switching to be controlled by CV or gates, set the pots to an appropriate turn-on point.

- NLC build notes.
- NLC blog
- Facebook
- Muffs2016

You can find more NLC builds here.

Friday, 28 July 2017

Modular in the CarPark - inagurial event - Wollongong

Sunday, 16th July, 2017. 
Many thanks to Claude Spinelli & Andrew G for helping put this event together.

The location was Prosound and Lighting, Wollongong.
Address: 16 Flinders St, Wollongong NSW 2500

Anyone with a synth, drum machine, etc was welcome to come,watch and perform. The synth didn't have to be modular.

 Keyboards were welcome too. 

The event was free, with sausage sizzles and barista coffee.
A good place to network with electronic musicians in the Sydney/Illawarra area.
Lots of great tunes too.

If you would like to perform at the next gig please leave a message here or contact Claude at Pro Sound and Lighting. (02) 4226 1177

Open Frame 40 - Carriage works gig

I attended this gig a month ago. Loved it.
There were 3 artists:

Klara Lewis is Swedish.

She released her debut album Ett in 2014
In that same year she also released an EP, Msuic.

Sara Davachi is Canadian.

A post shared by jono (@dj_jondent) on
I think her instrument was a ARP odyssey.
It was difficult to tell from a distance.
Alessandro Cortini needs no introduction.

A member of NIN and a founding member of LA-based electronic band Modwheelmood.
He also recorded as Blindoldfreak (esp. when using his Buchla 200e)
Alessandro is also the front-man for the band SONOIO and a member of the band The Mayfield Four.

The Avanti performance was beautiful and heartfelt especially with the backdrop of those old super 8 family videos shot by his grandfather of a young Cortini playing with a wheelbarrow.
I wish I could have recorded it all ... there were visits to the seaside, pictures of Venice,
a wedding. Very emotional and personal.

I received lots and lots of questions regarding what instruments Alessandro used.
I'm not really sure as I never got close to the stage. But the general consensus seems to be
that the sounds were of a EMS synthi, performed with a 4 track tape recorder.

"'AVANTI’ was written and recorded with an EMS Synthi AKS, but live I perform it with a TASCAM 4 track cassette player. It allows me to add another layer of expression to it, much different from the original creative one, while providing a certain degree of stability that the vintage machine wouldn’t be able to provide….with plenty of room for random and happy mistakes if needed."

Shwenandaw Monastery - Mandaly, Burma

Shwenandaw Monastery is located near Mandalay Hill, Mandalay Region, Myanmar (formerly Burma).

Its also known as the Golden palace monastery.
  built in 1878 by King Thibaw Min.

The building was originally part of the royal palace at Amarapura, before it was moved to Mandalay

 The building was heavily gilt with gold and adorned with glass mosaic work.

This is a section of the ceiling.

This was once covered with gold leaf.

Shwe Nan Daw Kyaung is famous because it is the only palace building which is left from the destruction of WWII. The Royal palace was burnt down in 1945.

For more travel postcards click here:

Wednesday, 12 July 2017

NLC Plague of Demons

Plague of Diamonds Eurorack module build notes.

Checkout electronotes EN #75.

It's a thru zero VCO that uses analogue switches (DG202) rather than FW rectifiers.
Should be easy to use; LEDs indicate when it crosses zero. 

My understanding of the through-zero concept is that with a regular VCO, if the frequency modulation reaches or goes below 0, you won't hear anything. With a thru zero VCO, you'll hear "negative" frequencies.  

"The negative-frequency version of a waveform is simply a time-reversed replica of the original waveform". (Ian Fritz. 2009)
Check out Dave Brown's scope shots on his site (
of the Ian Fritz "teezer" Thru-Zero VCO
They explain the concept so well.
The BOM requires:
a S1JL rectifier
Mouser No: 821-S1JL

and a JFET
Mouser No: 512-MMBFJ108

Both have a long backorder wait at mouser.
So possible replacements are:
mouser no: 771-PMBFJ108-T/R for the JFET
Mouser Part No: 583-FM4005-T for the recitfier.
The rectifier is polarized. The cathode end is marked with a band. 

This replacement is slightly too big for the PCB. so i had to solder it on its side.
On the PCB, I think Andrew has marked the cathode with a dot.

NLC words of wisdom

I like to get the ICs on first.

I'm using PCB version 2, so some mods are needed.
Had to cut one trace and add two resistors (10k & 2.2M).
Be careful not to short anything ... its a bit tricky

Q1. Its a PNP/PNP matched double trannie.
I used a microscope to find the dot that helps orientate it. But if your eyes are better than mine you could do without the scope.

The 1K tempco resistor.

INSTAL headers. theyconnect the two PCBs.

* NLC Blog
* Build notes
* Electro-music (Ian Fritz)
* mUFFwiggler

You can find more NLC builds here.