Unrefined industrial from my synth using three oscillators (power starved), one LFO, a 4040 divider, and a weird vactrol low-pass filter.

On/Off by RA Isle

Playing with the WSG VCF and a voltage controlled (sort of?) low pass filter (which uses a homemade vactrol) that I just built (I'll probably draw up a schematic soon). Everything is kept in time with a 4040 divider.

Vactroll by RA Isle

Synth work kind of stalled for a bit because I renovated a house and then moved into it. But now that things are settled down I've had time to build/break/fix a few things for my modular (which I should probably name at some point).

Things built:

• 4040 divider: This is based off of a schematic which can be found in Handmade Electronic Music: The Art of Hardware Hacking, by Nicolas Collins. I built this awhile ago, but fried it with the soldering iron (oops). Then fixed it by putting in an IC socket and a new IC. Then it had some problems with diodes and I had to reconfigure the divider as well as my LFOs/Clocks and my oscillators. It seemed to work, but not quite in the fashion I imagined it would (the frequency division was wonky and kind of choppy at certain clock speeds. I finally got around to re-examining it and I realized that I forgot to solder one of the power wires! Now it works great and has the added bonus of acting all weird and choppy when the power is off (which, in my opinion, often sounds more interesting.
• Pulse Width Divider: This had been troubling me for some time. I was happy with my LFOs/Clocks, but they had no PWD option and thus there was no way for me to get short pulses with large intervals between them. I had tried to build the PWD Pete Edwards has in his schematics for the Drone Lab but I could never get it to work. After a bit of reading, thinking, and breadboarding, I figured out that if I wanted the output of the PWD to modulate the oscillators, I would have to amplify the signal. I fail at transistors, so I used a 4049 as an amplifier (as seen in Handmade Electronic Music). The final design consists of one clock input, three amplified PWDs, and three outputs. It is not the easiest thing in the world to get the hang out (it can take a bit of work to find the sweet spots), but creates a lot of possibilities.

Here is a short little sample of what things are sounding like. In this I'm using one LFO/clock to drive the the PWD. The three outputs are modulating three oscillators. Two of the oscillators are going directly to the mixer, while one is going into my Barbie Echo and then through the Passive Tone Control before getting to the mixer. Note: The beginning and the end are just power starve noise. I love power starve.
Memorial Weekend Synth by RA Isle

Upcoming Modules:

• Delayed Pulser by Ian Fritz
• Sequencer
• CV inputs for the oscillators
• CV inputs for the MFOS VCF
• More oscillators (triangle and ramp, for starters)
  

Future Modules:

• Mangled Speech Sound Source (circuit bent)
• Noise source
• CV inputs on EVERYTHING (not really)
• Bigger mixer
• Vactrol filters
• More dividers

New stuff for my modular patchable squarewave synth!

First: I finally got around to building a VCF. Its Ray Wilson's (Music From Outer Space) design from his Weird Sound Generator (which I originally found through Fluxmonkey). It is probably the most complex circuit I've built so far, but it was worth the struggle!

Second: I built an echo module by modifying a Barbie Karaoke toy. Again, most of the hard work was done by Pete Edwards of Casper Electronics. My Barbie Echo Module has three pots for echo pitch adjustment, one for decay, and one for feedback. I still have to built a power source for it, though, as it runs on 6 volts and my synth runs on 9 volts, and I only want to have to use one wall-wart when the thing is finished.

Third (and Fourth): I built two Passive Tone Control/Filters. I was introduced to the Passive Tone Control through Getlofi.com (I think), which had a video of Properboy's PSC stomp box thing. Then I found this schematic and decided I had to build two. It is such a simple little thing but the control over tone is fantastic. It acts very similar to a bass/treble balance.

Here is another example of how things are sounding. In the "song" two oscillators are going through the Barbie Echo and then through the Passive Tone Control. The third oscillator just goes straight to the mixer and evidences how the echo and Passive Tone Control change the sound.

Playing with the Passive Tone Control and Barbie Echo. by RA Isle

Up next is a sequencer, another VCO, some dividers, some better mixer controls, CV/gate input for the VCF, a two-band pass filter, and so on and so forth. Oh, and the "keyboard" and rack and... So much to do!

More squarewave synth tinkering (4 tracks):


Birds by RA Isle

As mentioned before, I accidentally fried my Barbie Echo Box (which is a circuit bent Barbie karaoke toy converted into a lo-fi echo processor). Luckily, I still had two other Barbie Karaoke toys (one bent, one whole). So I un-bent and the then re-bent the already bent one and put it in the original enclosure. I won't lie, I got a good deal of help from Casper Electronics' page on Barbie bending. I did a few things differently, but overall, the hard work was done by Casper Electronics. I'm pretty happy with the results. There is, however, a bit of a hum on the line and the signal comes out really loud. Not sure how/if I'm going to fix the hum, but I plan on adding a volume control on the output. Pictures will happen once I finalize the enclosure design and buy some knobs (hopefully some ugly green ones). But for now, here is a sample of how it sounds when processing my DIY squarewave synth:

Barbie Echo Box by RA Isle

Things are coming along nicely. The LFO section and VCO section are done. The getlofi.com delay section is awaiting a friend (likely a circuit bent echo) and the mixer needs some banana-to-pot-to-banana modulation controls. I rushed the mixer because I was sick of hooking things up to speakers with alligator clips, thus it wasn't planned out super well. Thankfully, I measured it out with the intent to expand. Probably going to work on that this week. I also need to start on the filter section (thee passive tone controls and a VCF). Then build another enclosure. And then some other stuff... When will it end?!? Here a little sample of what it sounds like:

DIY Synth Demo by RA Isle