Analog Square Wave Sequencer V1

[mattoverse]

Here are some pics and video of version 1 of an 8 step square wave sequencer I finished recently. 40106(clock) / 4017 / 4046 (VCO) / OPA2134 (FILTER) Learned a lot during the first build and making a number of changes with the second build, reference last pic of populated chassis.  The big problem is I could use a deeper enclosure than the 1590DD, especially for version 2. 

V1 Features:
Selectable Sequence Step length of 1, 2, 3, 4, 6, or 8 steps
8x Bourne Multi-Turn Pitch Control Pots (much more precise pitch control than a standard potentiometer)
Fixed Resonance Sweepable Filter
Sequence Speed Control
Switchable and speed controllable 2nd oscillator
Volume Control
1/4" Mono Output

Version 2 is in the works now, with a different clock and more features, but I can already tell it is going to be very tough depth wise to fit the board in the box with the controls, ugh.  4093(clock) / 4017 / 4046 (VCO) / NE5532 (Buffer & Filter)

V2 Features:
Selectable Sequence Step length of 1, 2, 3, 4, 6, or 8 steps
Standard Linear Pots
Resonant Filter with Frequency & Resonance Controls (vactrol controlled)
Sequence Speed Control
2nd Clock / LFO which can be routed to the main clock or to LFO Speed
Pause and Reset Buttons
Portamento Button
Clock 1 into Clock 2 (for shifty rhythms)
CV Out
Volume Control
1/4" Mono Output

[hymenoptera]

I would LOVE to build something like this! Do you have any documents available for schematics, layouts, etc? Did you etch the PCB, or use vero/perf?

[mattoverse]

Will try to get a schematic posted later this week once version 2 is finalized.  The circuit itself isn't overly complex, but having to wire up 8 - 10 step pots (which also makes the schematic giant), plus another 5 pots, and 5-6 switches, + outputs, power etc.. ends up being a bit of rats nest.  For version 2 I am trying to link the grounds on all the step pitch pots and indicator LEDs to reduce the amount of wires going to the board.

For version 1 I used Vero.  I have done some etching in the past, but I am hand drilling the holes with a single speed dremel, so one slip can sort of ruin a board, so will probably use Vero for version 2.

My ultimate goal is to get an actual PCB manufactured, possibly even one partially assembled with SMD parts, will see if I can sort it out..

[hymenoptera]

Right on. Looking fwd to what you come up with. This is exactly the sort of noise makers I want to build!

[mattoverse]

Alright, here is the schematic for version 2.  I took what I had off the breadboard and redid based on this finalized schematic and it seems to work as planned.  Sorry for the confusing schematic, not an expert, and with all the switches and knobs, it can get out of hand pretty quick.  This is for 8 steps, though you can do 10 or less.  The two LDR's in the filter are both heat shrinked to the same LED (D4) in the schematic.

[kaycee]

For a noise box that's pretty musical. Very nice project, great work putting that together, I like it. Recently bought myself a little Korg synth, it's nice, but you seem to be getting more usable sounds out of your project, so we'll done!

Unfortunately, the schematic is not showing up for me on an iPad? Would be interested in having a go at this myself.

[hymenoptera]

Image isn't showing for me either.

[mattoverse]

Trying to post this again here, the last image was big so tried to link it from a different site of mine and use a smaller image.
I am really liking version 2 better than version 1 for overall sound.
Version 2 Features:
Up to 8 steps with 1, 2, 3, 4, 6, or 8 steps selectable.
2 Switch Selectable Clock Sources, you can also feed clock source 1 into clock source 2 for some fun rhythmic effects.
Resonant vactrol control filter that can be modulated with clock source 1, clock source 2, or clock1>2
Pause, Reset, and Portamento buttons.

I am definitely no expert so I am sure there are improvements that could be made, but I am really happy with how it is working on the breadboard, can get some pretty wild effects by modulating the filter with the different clock sources.  Will probably do the first real build with vero as I have already wired up a number of the offboard components, but I am aiming to figure out how to get a pcb manufactured, though I am worried that the board size may be slightly larger than the limit of the free version of Eagle, and don't much want to start learning a new CAD package.

[VidSicious]

It would be absolute balls if you published the vero layout of either ver 1 or ver 2. I am looking at building my first noise maker and this most definitely looks like it! (yeah, I have considered Atari Punk Console but this seems like a good challenge)

[mattoverse]

Will try to post the Vero once I have verified it, however it will be very confusing because I wired a number of LED's etc.. off board.  I would definitely not recommend this for your first noisemaker project.  The circuit itself is not particularly difficult but with 14 potentiometers, 3 jacks, and 7 switches, there is a lot of chance of running into issues.

[hymenoptera]

I don't do vero, but I'll buy some and learn just to build this. This is great! I've got me eye on this one. 

[VidSicious]

Keep our eyes peeled. I might build Atari punk console first then. 14 pots is quite a lot but trying is the beat way to learn, in my opinion. If it works on the first try, then it's one big step forward. If it doesn't then you go to something simple and build up to bigger projects.

In any case, your noisemaker sounds incredibly interesting. The tonality is quite rich.

[hymenoptera]

In any case, your noisemaker sounds incredibly interesting. The tonality is quite rich.

Right!? Now imagine it followed by a nice long delay and some reverb. Would sound huge!

[mattoverse]

Decided to do a quick breadboard demo of V2 before I start to finalize wiring and get this thing installed in the enclosure (pictured)

[hymenoptera]

Sounding good!

I just had a thought. It might be fun to run the CD4017's reset line out to a jack to permit retriggering from an external source. For instance the first downbeat ("one") of a drum machine could trigger the reset at the beginning of every measure allowing a generic sync to other devices.

I don't know anything about synths, but I figure a comparator or something would be needed to force the trigger signal high for just a moment.

[mattoverse]

That could be really cool. I still have much to learn before I can realize all the ideas and options I would want to include.

[hymenoptera]

Could be as simple as strapping a transistor across the existing switch and biased just so that a strong enough signal caused a short 9v pulse to the reset.

Anyways, looking fwd to building one of these once you think you've got a working layout. Count me in!

[mattoverse]

Alright, finally got V2 all wired up and crammed into the enclosure and I think it is something I will not attempt again as it is very difficult to fit in the enclosure due to the amount of hookup wires.  Will try to get a proper demo recorded with some annotations and details on the functions but you can check out a test drive of V2 below.  I can post my vero layout, but I am afraid it will not be that helpful as hookup points have been annotated with shorthand and abbreviations and there is a ton of off-board wiring done in an effort to reduce the amount of wires running to the board itself.  Also, if anyone wants to collaborate on a PCB layout that utilizes board mounted components I would be very interested.  I would recommend using the schematic as a guide, building up a basic version, then add switchable features as desired.  Now I feel the need to take a break from sequencer building for awhile...

V2 features are as follows:
8 steps max, select-able as 2, 3, 4, 5, 6, or 8 steps.
2 switch select-able clock sources, also switch select-able option to drive Clock 2 with Clock 1
Clocks are used to set tempo/speed and/or to set the rate of the filter modulation LFO
Resonant Filter
Pause Button
9v battery or DC Power
CV Out
1/4" Out
Portamento Button

[hymenoptera]

That thing is completely evil. I grinned the whole time! 

[peterg]

I'm working on a PCB layout with all components on it. Is there anything I should take into consideration re adjacent traces, component proximity, etc?