Glacial Communications

On Saturday, I finished mounting the Sound Lab into the dead scanner chassis:

Tonight, I threw together the Critter and Guitari Arduino Pocket Piano Arduino Shield.

Some quick thoughts:

• Critter and Guitari’s instructions aren’t very good. Use Make’s.
  
• Why no sockets, C&G? I ended up soldering the multiplexers in sans sockets, but used one of my own for the DAC chip.
• It’s kind of a pain (for me) to upload new programs – my only “shieldworthy” Arduino board is an NG – and thus I have to hit the reset button to upload a new program. As long as I have a little thin stick with me, I’ll be ok. For anyone just getting on board the Arduino train, you’ll probably be using a Diecimila and won’t have this problem – it autoresets when you upload a program.
• The “FM Synthesizer” program is quite fun. It’s no DX7, but you can edit multiple parameters at once, unlike a DX7…

Now to figure out an enclosure…

Also, does anyone know of any programs for the Pocket Piano other than C&G’s? A quick search didn’t turn up much.

Made some improvements to the MFOS Sound Lab and Arduino Sequencer last night:

1. Actually connected the Sound Lab CV inputs and audio output to the correct jack connectors. CV works now! Audio works better – it had been making audio output, but it just seemed thin and quiet. That’s no longer the case!

2. Ran the CV output of the Arduino Sequencer through this low-pass filter design. Hopefully that’ll smooth things a bit.

3. Started on the S-trig gate output for the sequencer.

Near-term plans:

1. Finish the S-trig gate output.

2. Slice off about 1/4″-1/2″ of the Sound Lab front panel, so that it fits the scanner chassis I’m putting it in.

3. Add note length and transpose controls to the sequencer.

4. Make a better demo video.

Sound Lab: Mostly done (after a 4-5 hour marathon on it last night). Here’s a rough looking demo:

Arduino Sequencer: I talked about that Thursday. I showed it off at Playshop on Saturday to rave reviews (i.e. “you should try to sell those”). I suppose I could try, but there really isn’t that much to it – a generic PCB, the CD4051, a 220 ohm resistor and then the pots and connectors. Any interest in a kit?

SN-Voice: PCB has been received, and I think almost all parts are on hand or en route(I think the tempco is the only outstanding part). Still unsure of how to enclose it – Standalone? In some kind of modular-style rack? Something in-between with a simple VCF and LFOs attached?

Other yet-to-be determined projects: Things are being determined. More information soon.

Playshop involved playing with the 556. It wasn’t an APC, but more of a plain “beeper” thing with fixed frequencies. Y’know, I prefer the 4093 to the 556. You get twice as many oscillators out of it.

And I think with the two big successes this week, this is the last “Summer of Synth-DIY” post for the year. New ones will just be “SynthDIY update” or maybe something specific to the project.

Made a somewhat big change last night. We’ll call it 1.6, since 1.0 was the “Notacon Edition”, and 1.5 was the stable version of that which was finished a few weeks ago.

New Features:

• Note “0″ is now a rest.
• “CV” (ok, PWM masquerading as 0-5V CV) and Gate outputs. S-Trigger (for my MG-1) coming soon.
• Added 9V battery clip, so it can run on batteries. Yay! Should add a real power switch for that, though.

Construction – I need to update the schematic to reflect reality, but the original “plan” schematic is here.

Differences between that schematic and reality:

• The A,B, and C inputs on the CD4051 connect to pins 6,7 and 8 on the Arduino
• Arduino pin 9 goes to the tip of a 1/4″ jack (CV)
• Arduino pin 5 goes to the tip of a 1/4″ jack (Gate)
• For S-Trig, follow the “V-Trig to S-Trig” instructions here. I’ll be adding an additional jack for this, probably tonight. (hey, then I can have a duet of MG-1 and my soon-to-be-finished Sound Lab)
• None of the LED/Start/Stop/Clock stuff is implemented yet. The more of that which gets done, the closer we are to being “2.0″. Stay tuned.

Source Code:

• available here: sequencer_1.pde

I’ll have to whip up a demonstration video or something like that. I tried it with my somewhat wonky MG-1 last night (yeah, even though it triggers weird with gate rather than S-Trig, it still mostly worked) – it was like instant Jack Dangers.

Not a lot to report, as expected.

Sound Lab: Finished mounting switches on panel, started mounting components onto panel (39k 1% resistors went AWOL? Ugh.). Drilled holes for 1/4″ jacks along the top of the panel. Trying to finish this thing quickly.

Arduino Sequencer: Made a quick code change (Note #0 is now equal to a rest). Will probably have to make a small wiring change in order to add an AWESOME new feature (at least, I hope it’s awesome…)

Drum Box…OF DOOM! : Planning. Pledged to get a batch of SDS3 voice boards.

Modular: Planning. Still trying to determine requirements, etc.

Other: Taking an interest in Ken Stone’s Junkbox Challenge. I have a whole box of random parts (most from old VCRs, I think, that’s ripe to be used for this.

I think these updates will have a new title soon, since summer’s effectively over.