Sequential Circuits Pro-One

Posted on March 12, 2010 by John C.S. Keston

I have finally started restoring my Sequential Circuits Pro-One. My plan is to get it as close to mint condition as possible and start using it again for recording and perhaps performing. Once I started using the Korg MS2000, I neglected the Pro-One and it fell into disrepair. Over time the key contacts became dirty and inconsistent. At some stage one of the knobs was broken off and lost, leaving a stub of potentiometer protruding uselessly from the control panel.

The first thing I did was clean the pots. For you laymen, pots is short for potentiometers. In other words, I wasn’t diverted by dirty dishes. To clean the pots I removed the knobs and then squirted a few drops of a greaseless lubricant called LPS-1 around the post. The stuff works wonders on crackly volume knobs and was recommended to me by the electronics experts at AEI Electronics in Minneapolis years ago. I’ve been using it ever since. After applying the LPS-1 I made thirty or more rotations of the pot from zero to maximum so that the dirt particles were worn away by the fluid.

I put the thing back together and did some tests. The knobs no longer had anymore crackling going on, so that was fixed, but the keyboard was horribly inconsistent. The Pro-One uses a J-wire keyboard with open air connectors that are prone to collecting dirt (or residue from malted beverages spilled over the keys). For a close up view of the Pro-One J-wires check out this post on MaxtrixSynth. Another problem is that the J-wires can become less springy, making the connections a bit weak. I used used q-tips with a drop of LPS-1 to clean each J-wire and the metal bar that they connect to when the key is depressed. I also bent the J-wires slightly to improve the tension. After all that I tested it again to find it working flawless, although still a little difficult to tune. Next up I’ll be replacing the missing mod wheel, the broken potentiometer, and the missing knob.

Audio Cookbook on Make: Blog

Posted on January 28, 2009 by John C.S. Keston

Yesterday afternoon the popular and renowned Make: Blog posted an article about my recent ACB entry, Processing Sound Using Photoshop. From the article:

Over at Audio Cookbook, John Keston has been running a few experiments with using image filters in Photoshop to process sound. Running the audio data through a Gaussian blur or Spherize filter, he was able to create some incredibly diverse effects from a simple electric piano input.

Thanks to Make: Blog author Jason Striegel for the good words. Checkout the full article over on the Make: Blog website. In addition to Make: the article has been written about on many other blogs in English and German including Synthtopia and Media Synesthesia. Who knew it would create such a stir?

Live Looping: Not Just for Breakfast Anymore

Posted on January 18, 2009 by John C.S. Keston

A few years ago I created a technique for live looping in Ableton Live. I wanted to record and stop recording a clip in the session view without using a bulky MIDI foot controller. So, I came up with the idea of modding a mouse by connecting a simple sustain pedal into the left button. This way I could keep playing my instrument with both hands and record to any clip that the mouse cursor was resting on.

I found that I could do lots of other things while continuing to play two handed, like start a scene, stop a clip, mute a track, etc. Usually I reserve setting up my modded mouse for shows, but it’s a very useful tool in the studio for capturing two handed keyboard parts, like the Rhodes in this segment from a new track.

Live Looped Studio Rhodes

Noises from the Arduino

Posted on January 18, 2009 by Michael Koppelman

The Arduino is a little programmable doo-hickie that can be used for lots of things. I was playing with mine recently and hooked the digital outs up to an analog sound board. This is a common thing to do with the Arduino. You can coax the thing into making analog-like sounds through the digital output. Since it is digital, everything is a square wave.

All of these sounds were made with a little routine I got from the sample code for making a sound:

void playTone(int tone, int duration) {
  for (long i = 0; i < duration * 1000L; i += tone * 2) {
    digitalWrite(speakerPin, HIGH);
    delayMicroseconds(tone);
    digitalWrite(speakerPin, LOW);
    delayMicroseconds(tone);
  }
}

Here are a few little audio samples that I made tonight whilst fooling around. The first one is just random frequencies:

long i = 0;
  
i= random(5, 100);
playTone( i*i, 100 );

Arduino Random

The rest are just a sweep using different durations:

 
for(int i = 5; i < 100; ++i ) {
    playTone( i*i, 50 );
  }
for(int i = 100; i >= 5; --i ) {
    playTone( i*i, 50 );
}

Arduino Sweep Slow

Arduino Sweep Medium

Arduino Sweep Fast

Arduino Sweep Very Fast

It has digital and analog inputs as well, so my next goal is to use some sort of control voltage to make noises. More to come!

Segment of Piano Piece with Rhodes

Posted on January 8, 2009 by John C.S. Keston

With help from my father who was visiting recently, I have built a new desk for my studio. The idea I had was to build a desk wide enough to build a keyboard drawer underneath. What I came up with was a simple design using three quarter inch plywood, quarter inch ply for the backing and one by three pine for a brace and attachments for the eighteen inch ball bearing drawer runners. The keyboard is a CME UF7 semi-weighted controller.

It has made a huge difference in the ergonomics of my studio to have this controller readily available without having to have it take up extra space on a stand. Here’s a segment from a piece I wrote soon after putting the studio back together with the new desk. I’m using the CME to control my the grand piano patch on my Yamaha A3000 rack mount sampler. The Rhodes is my 1976 suitcase model that does not leave the studio.