(This post was originally titled “Fixing a Small Organ Problem” but I thought better of it!)

Well, the digital organ at the Catholic Church is on the fritz again which prompted another visit from Keith, the formerly wild-n-crazy Santana FOH sound engineer now turned organ repairman.  Keith drove about 3 hours to get here and, as Murphy’s Law would have it, the organ worked perfectly while he was here.  He did some “soul-searching” and took apart the power supply and checked capacitors, but we still don’t know if it’s fixed or not.  We agreed that beginning to change out parts at this stage of the game was a waste of time, but if he had just a bit more information, he would know what to do on the next trip.

Basically, he gave me “THE LESSON” on how to troubleshoot a digital organ when your repair shop is 3 hours away.  Since I know so many of my readers would find this information useful, I decided to share it with you.  The trouble I’m having with this instrument is that it randomly sounds like fireworks going off at close range;  –not all the time, but just during times when people would be frightened to hear such loud low-frequency noise.

THE LESSON

Number One.  If the organ is acting up (i.e. making explosion sounds) during a service,  give up and turn it off.  People will likely leave to join another church if you leave it on.

Number Two.  If it acts up and no one would be alarmed by the noise, then leave it on and quickly perform the following steps:  (you’ll need a screwdriver).

  1.  
    1. Make sure you have full access to the rear panel (the side the organist can’t see if he’s playing).
    2. Using your phillips screwdriver, remove the two screws at the top of the back panel to expose the inner “guts”.  The first step is to Identify the two power amps at the bottom left of the organ; –they both look like they have 2 silver beer cans mounted on the metal boxes’ left side.  You’ll also see a heatsink-looking thing to the right of the transformer.  The amp on the left (assuming no one has screwed with the wiring) is for flute stops.  The amp on the right is the main amp. 
    3. Identify the silver shaft on the lower l.h. side of each of the amps.  This is volume but they don’t put a knob on it.   While the organ is acting up, turn one amp’s volume counterclockwise to see if the problem goes away.  This way you’ll know which amp/circuit boards may be involved.  When you’re finished, turn the shafts back to their original position.  DON’T TOUCH OTHER WIRES/PARTS WITH YOUR HANDS!   If you feel the need to bump things around a bit, use something with an insulated handle.
    4. Did I mention to remember the way the volume shaft was set before you turned it?  If you don’t really know, you’ll have to go back later and balance the flute stop volume against the other stops.  Not to much of a problem.
    5. Now look for the big honking circuitboard that is directly facing you.  This is mounted on a panel that you’ll need to swing open; –the screw that holds it in is to your left on the side.  Remove this knob/screw and put this somewhere safe;  you don’t want to lose it (or leave it off when you’re through).  
    6. Swing open the panel to expose all the circuitboards attached to its rear.  The one you’re looking for is the A/D converter board;  it has 2 RCA cables that plug into jacks soldered onto the board.  (Remember, the organ needs to still be powered on and acting up at this point, otherwise you’re wasting your time). 
    7. One at a time,  remove these cables from the board (noticing which one goes where!).  If the problem goes away at this point,  make a note of which cable has to be removed for the problem to cease.  Call your trusty repairman and he’ll know which circuitboards to bring based on which wire it is (top or bottom).
    8. If the problem is still happening, then fear not!  It is in the amp section.  Repeat step 3 to confirm if one or both is bad.
    9. Return everything back to its original position and close/secure the panel.  Replace the back and wait for the calvary to arrive.

See, that wasn’t so bad!  Anyone could do it!  It’s not very dangerous due to the low voltages inside MOST sections (and the nasty ones are supposed to be covered by grills!).  And it beats $300 pointless service call anyday!  (Actually, Keith isn’t charging for this past trip, except for the lightbulb for the pedalboard that I didn’t really need but took anyway).  

Now what have we learned, children?

–Basically we have to isolate the problem from the stuff that doesn’t matter.  Divide and Conquer.  Veni, vidi, vici.  Throw out the bathwater and keep an eye out for the baby.

We probably didn’t fix the organ today, but I learned an important lesson;  “THE LESSON” about fixing digital organs.  And hopefully, you learned something too.

Peace,

 

J