I can’t tell you how excited I am.
I just finished my mini-keys keyboard that I was working on (Mini-Keys — A little keyboard circuit bend (part 1)).
I’m so stoked on this that I can’t even think of a good way to tell about it. So, I’m just going to show you this second hand synth and let you be the judge.
The paint job and design
First off, I am really excited about the paint job. It’s not what I envisioned when I first thought of the design but it definitely is the best thing I have made to date.
It was inspired by the way the synth sounds when it’s oscillators are kicked on. It’s what I think insects sound like when they communicate with one another. Lot’s of super sonic chirps and squeaks.
Anyway, this paint job was tough to do too because I kept screwing up. I must have repainted it 3 or 4 times. Doing the stencils was increadably difficult. I found the images I wanted and printed them onto paper. Then I cut out the silhouette with an exact-o knife. Because the paint kept sparaying under the stencil and screwing up the whole thing, I finally decided that tape wasn’t enough to hold it down. I mixed some Elemer’s glue and water and coated the back of the stencil. That did the trick.
After the painting was finished, I made a couple of images in photoshop to label the keyboard and to put “SECOND HAND SYNTH” on the back of the keyboard. I cut them out from the plain white printer paper they were printed on and glued them to the keyboard. I tried t be cool and write 2010 on the back. I don’t know why I thought that was a good idea but I did it.
I really liked the synth identifying decal. “Insect-A-Tron”. Howerever, as soon as I had done it I realized that it should have been Insect-O-Tron. Oh well.
I finished the paint job with two coats of clear gloss. I used a polyurethane which I think had a little stain in it (it is for wood projects). It turned the white paint a little yellow. Not a lot. But enough so that it doesn’t have the cool, cold white feel to it. I’m gonna use real clear coat next time.
These are the controls on the left hand side. The top switch engages the oscillators. The bottom on is a bend that I found on my own circuit. It smooths out the warble of the oscillators. The Joystick in the center of the black panel controls the frequency of the oscillators. The black knob at the top of the picture controls the bottom switch’s saturation. I don’t exactly know what it is doing but is a bit like a depth knob on a flanger pedal.
This is the pitch knob. It is a washer glued to a little 1M potentiometer. It worked out quite nice. I just wish it was black. Maybe I will paint it someday.
This is the push botton switch that activates the custom dual oscillator chip that I added to the keyboard. I should have made it turn on the actual keyboards chip too.
The problems with this synth
The main problem so far is that there is no volume control. I am gonna have to get the output resistance right and solder it in there. The signal comes out quite hit and clips a lot of the sound. I had to rig a little pot in series with the keyboard just to make the video. For the life of me, I have no idea why that wasn’t part of the design.
The second problem is that there is a switch on the right hand side that activates the oscillator chips. The circuit board is powered by a 9v battery but the keyboard is powered by two AA batteries. You have to open up the entire case to get the 9v out. I guess it’s a good thing that there is a on/off switch for the 9v but I don’t like how it’s impossible to get the 9v out without taking it apart.
The third thing that I don’t like about this second hand synth is that some of the settings don’t make any sound. I wanted the most variety of sound so I didn’t dial in the resistances of the joystick very much. Because it’s not properly calibrated, when the timing resistance it too low, you get nothing.
Another problem is that the keyboard is a little filled up. There is so much packed into such a small case. Next time I will definitely map out where the wires will go before I get into that phase of construction.
The last thing that I should have done is to label the controls. I originally intended to have interesting insectoid names for all the switches and knobs. I was a little impatient and went on with out doing it. Again, oh well. Maybe I will bust out a sharpie and write it all on.
Oh! And, I forgot to put in the LED’s too. There is one for each LFO. Oh well.
I don’t even know how many hours I put into it. Many. Too many. Not enough. I don’t know. Just to get it all glued into the case it took me 3-4 hours.
Here is the first video.
Also, please click on any of the pictures and check them out on Flickr.com. There are tons more pics and you can view the larger resolutions too.