Sunday, April 16, 2006
Tiger Tunes
My 1970 EKO Tiger Organ fortunately worked after a little cleaning, but it was still out of tune, about a quarter note too low. Switching the main power selector from 220 to 240 volts changed nothing about that (which is good), so I opened the case again in search of a tuning knob. There is none.
There are, however, 12 oscillator circuits, one for each note of the octave, and each board has big tuning pots (or maybe variable capacitors; I don’t really know). So although the organ sounded fine when being played because all 12 notes were off the same amount from the standard tuning, I had to re-tune all 12 circuits.
I wanted it to be quite exact, as tuning means opening the whole device, something I don’t want to do too often, so I googled for a tuning program and the first thing I found is Instrument Tuner for Windows, which is shareware but works for 30 days. Having a frequency display that shows how much the current note is off made it quite easy to completey tune the organ in 20 minutes. Now I’m playing “House of the rising sun”.
